DRAFT Annual Operating Plan for Colorado River Reservoirs 2009

Transcription

1 DRAFT Annual Operating Plan for Colorado River Reservoirs 2009 U.S. Department of the Interior Bureau of Reclamation

2 TABLE OF CONTENTS INTRODUCTION...1 Authority...1 Purpose...1 Summary...2 Upper Basin Delivery...2 Lower Basin Delivery United States-Mexico Water Treaty Delivery HYDROLOGY SUMMARY AND RESERVOIR STATUS WATER SUPPLY ASSUMPTIONS...9 SUMMARY OF RESERVOIR OPERATIONS IN 2008 AND PROJECTED 2009 RESERVOIR OPERATIONS...11 Fontenelle Reservoir...12 Flaming Gorge Reservoir...12 Blue Mesa, Morrow Point, and Crystal Reservoirs (Aspinall Unit)...14 Navajo Reservoir...15 Lake Powell...17 Lake Mead...21 Lakes Mohave and Havasu...21 Bill Williams River...22 Senator Wash and Laguna Reservoirs...23 Imperial Dam...24 Gila River Flows...24 Additional Regulatory Storage (Drop 2 Storage Reservoir)...24 Yuma Desalting Plant...25 Intentionally Created Surplus...26 Demonstration Program...26 System Efficiency ICS...26 Tributary Conservation ICS...27 System Conservation of Colorado River Water Demonstration Program...27 Delivery of Water to Mexico DETERMINATIONS...29 Upper Basin Reservoirs...29 Lower Basin Reservoirs United States-Mexico Water Treaty...32 DISCLAIMER...34 ATTACHMENT I...35 i 2009 Draft AOP October 21, 2008

3 LIST OF TABLES Table 1. Reservoir Conditions on October 1, 2008 (English Units)...8 Table 2. Reservoir Conditions on October 1, 2008 (Metric Units)...8 Table 3. Projected Unregulated Inflow into Lake Powell for Water Year 2009 (English Units: maf)...10 Table 4. Projected Unregulated Inflow into Lake Powell for Water Year 2009 (Metric Units: mcm)...10 Table 5. Glen Canyon Dam Release Restrictions (Glen Canyon Dam Operating Criteria)...19 Table 6. Projected Monthly Releases from Lake Powell in Water Year 2009 Under Most Probable Inflow Conditions (English Units)...20 Table 7. Projected Monthly Releases from Lake Powell in Water Year 2009 Under Most Probable Inflow Conditions (Metric Units)...20 ii 2009 Draft AOP October 21, 2008

4 INTRODUCTION Authority This 2009 Annual Operating Plan (AOP) was developed in accordance with Section 602 of the Colorado River Basin Project Act (Public Law ); the Criteria for Coordinated Long-Range Operation of Colorado River Reservoirs Pursuant to the Colorado River Basin Project Act of September 30, 1968 (Operating Criteria), as amended, promulgated by the Secretary of the Interior (Secretary); and Section 1804(C c)(3) of the Grand Canyon Protection Act (Public Law ). Section 602(b) of the Colorado River Basin Project Act requires that the Secretary annually prepare a report describing the actual operation under the adopted criteria [i.e., the Operating Criteria] for the preceding compact water year [i.e., from October 1 to September 30] and the projected operation of for the current year. In accordance with the Operating Criteria, the AOP must be developed and administered consistent with applicable Federal laws; the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, the Treaty Between the United States of America and Mexico, signed February 3, 1944 (1944 United States-Mexico Water Treaty); interstate compacts; court decrees; the Colorado River Water Delivery Agreement (69 Federal Register 12202, March 15, 2004); the Record of Decision 1 for Colorado River Interim Guidelines for Lower Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead 1 (Interim Guidelines) (73 Federal Register 19873, April 11, 2008); and other documents relating to the use of the waters of the Colorado River, which are commonly and collectively known as the Law of the River. The 2009 AOP was prepared by the Bureau of Reclamation (Reclamation) in consultation with the seven Basin States Governors representatives; the Upper Colorado River Commission; Native American tribes; appropriate Federal agencies; representatives of the academic and scientific communities, environmental organizations, and the recreation industry; water delivery contractors; contractors for the purchase of Federal power; others interested in Colorado River operations; and the general public, through the Colorado River Management Work Group (CRMWG). Article I(2) of the Operating Criteria allows for revision of this 2009 AOP by June of 2009 to reflect the current hydrologic conditions. This process for revision is further described in Section 7.C of the Interim Guidelines. Any revision to the AOP may occur only through the AOP consultation process as required by applicable Federal law. Purpose The purposes of the AOP are to determine or address: (1) the projected operation of the Colorado River reservoirs to satisfy project purposes under varying hydrologic and climatic conditions; (2) the quantity of water considered necessary to be in storage in the Upper Basin reservoirs as of September 30, 2009, pursuant to Section 602(a) of the Colorado River Basin Project Act; (3) water available for delivery pursuant to the 1944 United States- 1 A Record of Decision (ROD) adopting the Interim Guidelines was signed by the Secretary on December 13, Draft AOP October 21, 2008

5 Mexico Water Treaty and Minutes No. 242 and 310 of the International Boundary and Water Commission, United States and Mexico (IBWC); (4) whether the reasonable consumptive use requirements of mainstream users in the Lower Division States will be met under a Normal, Surplus, or Shortage Condition as outlined in Article III of the Operating Criteria and as implemented by the Interim Guidelines; and (5) whether water apportioned to, but unused by one or more Lower Division States, exists and can be used to satisfy beneficial consumptive use requests of mainstream users in other Lower Division States as provided in the Consolidated Decree of the Supreme Court of the United States in Arizona v. California, 547 U.S. 150 (2006) (Consolidated Decree). Consistent with the above determinations and in accordance with other applicable provisions of the Law of the River, the AOP was developed with appropriate consideration of the uses of the reservoirs for all purposes, including flood control, river regulation, beneficial consumptive uses, power production, water quality control, recreation, enhancement of fish and wildlife, and other environmental factors (Operating Criteria, Article I(2)). Since the hydrologic conditions of the Colorado River Basin can never be completely known in advance, the AOP addresses the operations resulting from three different hydrologic scenarios: the probable maximum, most probable, and probable minimum reservoir inflow conditions. River operations under the plan are modified during the year as runoff predictions are adjusted to reflect existing snowpack, basin storage, and flow conditions. Summary Upper Basin Delivery. Annual releases from Lake Powell during water year 2009 shall be made consistent with Section 6.B (Upper Elevation Balancing Tier) of the Interim Guidelines. Consistent with Section 6.B.1, the water year release from Lake Powell in 2009 shall be 8.23 million acre-feet (maf) (10,150 million cubic meters [mcm]) unless provisions in Section 6.B.3 occur. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2009, Lake Powell elevation to be greater than elevation 3,639.0 feet (1,109.2 meters), Section 6.A (Equalization Tier) of the Interim Guidelines will govern the release of water from Lake Powell for the remainder of water year 2009 (through September 2009). Lower Basin Delivery. Under the most probable inflow scenario, downstream deliveries are expected to control the releases from Hoover Dam. Taking into account (1) the existing water storage conditions in the basin, (2) the most probable near-term water supply conditions in the basin, and (3) Section 2.B.5 of the Interim Guidelines, the Intentionally Created Surplus (ICS) Surplus Condition is the criterion governing the operation of Lake Mead for calendar year 2009 in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. No unused apportionment for calendar year 2009 is anticipated. If any unused apportionment becomes available after adoption of this AOP, Reclamation, on behalf of the Secretary, shall allocate any such available unused apportionment for calendar year 2009 in accordance with Article II(B)(6) of the Consolidated Decree Draft AOP October 21, 2008

6 Water may be made available for diversion pursuant to 43 CFR Part to contractors within the Lower Division States. The Secretary shall make Intentionally Created Unused Apportionment (ICUA) available to contractors in Arizona, California, or Nevada for the off-stream storage or consumptive use of water pursuant to individual Storage and Interstate Release Agreements (SIRA) and 43 CFR Part 414. In calendar year 2008, approximately maf (30.84 mcm) of ICUA water stored in Arizona is anticipated to be recovered for use in California 3 by the Metropolitan Water District of Southern California (MWD). In calendar year 2008, approximately maf (18.50 mcm) of ICUA water from Nevada is anticipated to be stored in California by MWD. 4 In calendar year 2009, up to maf (43.17 mcm) of ICUA water stored in Arizona is anticipated to be recovered for use in California by MWD. The Southern Nevada Water Authority (SNWA) may propose to make additional unused Nevada basic apportionment available for storage by MWD in The Inadvertent Overrun and Payback Policy (IOPP), which became effective January 1, 2004, will be in effect during calendar year The Colorado River Water Delivery Agreement 6 requires payback of California overruns occurring in 2001 and 2002 as noted in Exhibit C of that document. Each district with a payback obligation under Exhibit C may at its own discretion elect to accelerate paybacks. In calendar years 2008 and 2009, paybacks occurring in California result from Exhibit C obligations and IOPP overruns. During calendar year 2008, the California paybacks are projected to total maf (54.27 mcm). In calendar year 2009, California paybacks are projected to total maf t (4.934 mcm). During calendar year 2008, the Arizona paybacks are projected to total maf t (0.740 mcm). In calendar year 2009, Arizona paybacks are projected to total maf t (0.370 mcm). Nevada incurred no payback obligation for In calendar year 2009, Nevada paybacks are projected to total maf (0.160 mcm). The Interim Guidelines adopted the ICS mechanism that among other things encourages the efficient use and management of Colorado River water in the Lower Basin. ICS may be created and delivered in 2009 pursuant to the Interim Guidelines and appropriate delivery and forbearance agreements. 2 Off-stream Storage of Colorado River Water; Development and Release of Intentionally Created Unused Apportionment in the Lower Division States: Final Rule (43 CFR Part 414; 64 Federal Register 59006, November 1, 1999). 3 Amendatory Agreement to Agreement between the Central Arizona Water Conservation District and the Metropolitan Water District of Southern California for a Demonstration Project on Underground Storage of Colorado River Water, December 1, Storage and Interstate Release Agreement among The United States of America, acting through the Secretary of the Interior; The Metropolitan Water District of Southern California; the Southern Nevada Water Authority; and the Colorado River Commission of Nevada, October 21, Record of Decision for Implementation Agreement, Inadvertent Overrun and Payback Policy, and Related Federal Actions, Final Environmental Impact Statement, October 10, Colorado River Water Delivery Agreement: Federal Quantification Settlement Agreement for Purposes of Section 5(B) of Interim Surplus Guidelines, October 10, Draft AOP October 21, 2008

7 In 2006, Reclamation implemented an ICS Demonstration Program in the Lower Basin. The ICS Demonstration Program allowed entitlement holders to undertake extraordinary conservation activities in 2006 and 2007 to reduce their approved annual consumptive use of Colorado River water and account for that conserved water in Lake Mead. The ICS credits created and accounted for under the ICS Demonstration Program becomes available for delivery pursuant to the Interim Guidelines and appropriate delivery and forbearance agreements. In calendar year 2006, MWD created maf (61.67 mcm) of ICS credits. 7 In calendar year 2008, MWD is anticipated to recover up to maf (56.74 mcm) the balance of ICS credits created under the ICS Demonstration Program. 7 If MWD has not recovered all of its Demonstration Program ICS credits during calendar year 2008, MWD may request delivery of those credits during In calendar year 2007, the Imperial Irrigation District (IID) planned to create maf (1.234 mcm) of ICS credits under the program. 8 Pursuant to the IID ICS agreement, the conserved water was applied to reduce its 2007 IOPP overrun. In 2006, Reclamation implemented the System Conservation of Colorado River Water Demonstration Program (SC Demonstration Program) in the Lower Division States Basin which allows entitlement holders to participate in voluntary conservation to conserve a portion of their approved annual consumptive use of Colorado River water in exchange for appropriate compensation provided by Reclamation. Reclamation extended the SC Demonstration Pprogram through December 31, The water System Conservation Water (SC Water) conserved (SC Water) is retained in Lake Mead to assist in providing an interim, supplemental source of water to replace the drainage water from the Wellton- Mohawk Irrigation and Drainage District (WMIDD) that is bypassed to the Cienega de Santa Clara (Cienega) and the reject stream from operation of the Yuma Desalting Plant (YDP). In calendar year 2008, approximately maf ( mcm) of SC Water is projected to be created by Yuma Mesa Irrigation and Drainage District (YMIDD) and retained in Lake Mead. 10 In calendar year 2009, approximately maf (4.317 mcm) of SC Water is projected to be created by YMIDD and retained in Lake Mead. 11 In 2007, Reclamation signed a funding agreement for the construction of the Drop 2 Storage Reservoir. In exchange for project funding, SNWA has received maf (493.4 mcm) and MWD and the Central Arizona Water Conservation District (CAWCD) have each received maf (123.3 mcm) of System Efficiency ICS credits. In calendar year 2008, MWD is anticipated to take delivery of maf (41.94 mcm) of its System Efficiency ICS credits, and may request delivery of up to maf (41.94 mcm) of these credits in Agreement between the Bureau of Reclamation and MWD to Implement a Demonstration Program to Create Intentionally Created Surplus Water, May 18, Agreement between IID and Reclamation to Implement a Demonstration Program to Create Intentionally Created Surplus Water, June 26, Extension of Policy Establishing a Demonstration Program for System Conservation of Colorado River Water, September 16, Agreement between the United States Bureau of Reclamation and the Yuma Mesa Irrigation and Drainage District to Implement a Demonstration Program for System Conservation of Colorado River Water, February 4, Agreement between the United States Bureau of Reclamation and the Yuma Mesa Irrigation and Drainage District to Implement a Demonstration Program for System Conservation of Colorado River Water, October 7, Draft AOP October 21, 2008

8 Upon approval by the Secretary of an ICS creation plan, SNWA anticipates creating and taking delivery of Tributary Conservation ICS credits from projects on the Muddy and Virgin Rivers. SNWA anticipates creating and taking delivery of maf (19.74 mcm) of Tributary Conservation ICS credits in 2008, and maf (37.00 mcm) in United States-Mexico Water Treaty Delivery. A volume of maf (1,850 mcm) of water will be available to be scheduled for delivery to Mexico during calendar year 2009 in accordance with Article 15 of the 1944 United States-Mexico Water Treaty and Minutes No. 242 and 310 of the IBWC Draft AOP October 21, 2008

9 HYDROLOGY SUMMARY AND RESERVOIR STATUS Above average streamflows were observed in the Colorado River Basin during Unregulated 12 inflow to Lake Powell in water year 2008 was maf (15,241 mcm), or 102 percent of the 30-year average 13 which is maf (14,876 mcm). Unregulated inflow to Flaming Gorge, Blue Mesa, and Navajo Reservoirs was 59, 133, and 120 percent of average, respectively. Basin-wide precipitation during water year 2008 initially trended drier with near average conditions occurring in October 2007 followed by well below average conditions in November. In December, however, precipitation rebounded and was well above average in the basin during December, January, and February. Snowpack conditions on March 1, 2008, were 124 percent of average. By mid-april, the snowpack was 122 percent of average. Snowpack conditions trended drier in water year 2008 in the Upper Green River Basin in comparison to the Upper Colorado River, Gunnison River, and San Juan River basins. On April 1, 2008, the Upper Green River Basin snowpack measured 95 percent of average while the Upper Colorado, Gunnison, and San Juan Basins measured 119 percent, 137 percent, and 125 percent of average, respectively. Inflows to Lake Powell during April and May were below forecasted levels due to below average temperatures. By late May, however, inflows increased to more than 75,000 cubic feet per second (cfs) (2,123.8 cubic meters per second [cms]) with Lake Powell elevations increasing by more than 1 foot per day. The observed unregulated inflow volume to Lake Powell during the April through July period was maf (10,985 mcm), 112 percent of average. Inflow to Lake Powell has been below average in seven out of the past nine years. While drought conditions eased in 2005 and 2008, and the inflow in 2006 and 2007 was not as low as what occurred in 2000 through 2004, drought conditions in the Colorado River Basin persist. Provisional calculations of natural flow for the Colorado River at Lees Ferry, Arizona, show that the average natural flow since calendar year 2000 ( , inclusive) is the lowest nine-year average in over 100 years of record keeping on the Colorado River. Tributary inflows in the Lower Basin were below average for water year 2008 except for the Little Colorado River. Although drought conditions eased for central Arizona, drought conditions persisted for water year 2008 in other parts of throughout the Lower Basin and the southwestern United States. 14 Abnormally dry to moderate drought conditions persisted throughout in far western Arizona and southern Arizona, southern California, and southern Nevada. 14 However, because of above average snowpack in on the Gila, Salt, and Verde River watersheds, the Gila River Basin experienced 110 percent of average precipitation for 12 Unregulated inflow adjusts for the effects of operations at upstream reservoirs. It is computed by adding the change in storage and the evaporation losses from upstream reservoirs to the observed inflow. Unregulated inflow is used because it provides an inflow time series that is not biased by upstream reservoir operations. 13 Inflow statistics throughout this document will be compared to the 30-year average, , unless otherwise noted. 14 From the U.S. Drought Monitor website: August 26September 30, Draft AOP October 21, 2008

10 water year During water year 2008, no tributary inflow from the Gila River reached the mainstream of the Colorado River. 15 Tributary inflow from the Little Colorado River for water year 2008 reflected above average conditions in northern Arizona. Tributary inflow from the Little Colorado for water year 2008 totaled maf (254.1 mcm), or 114 percent of the long-term average. 16 By contrast, tributary inflow from the Bill Williams River into the mainstream totaled maf (35.77 mcm) for water year 2008, or 28 percent of the long-term average. Tributary inflow from the Virgin River for water year 2008 experienced below average conditions, totaling maf (143.1 mcm), or 67 percent of the long-term average. Above average inflow to Colorado River reservoirs in water year 2008 resulted in a net gain in the Colorado River total system storage in the amount of maf (2,389 mcm). Reservoir storage in Lake Powell experienced an increase during water year 2008, increasing by maf (3,182 mcm). Reservoir storage in Lake Mead declined during water year 2008 by maf (607 mcm). At the beginning of water year 2008, Colorado River total system storage was 54 percent of capacity. As of September 30, 2008, total system storage was 57 percent of capacity. 15 Tributary inflow from the Gila River to the mainstream is very sporadic. These flows occur very seldom and when they do they are typically of high magnitude. 16 The basis for the long-term average of tributary inflows in the Lower Basin is natural flow data from 1906 to Additional information regarding natural flows may be found at Draft AOP October 21, 2008

11 Tables 1 and 2 list the October 1, 2008, reservoir vacant space, live storage, water elevation, percent of capacity, change in storage, and change in water elevation during water year Table 1. Reservoir Conditions on October 1, 2008 (English Units) Reservoir Vacant Space Live Storage Water Elevation Percent of Capacity Change in Storage * Change in Elevation * (maf) (maf) (ft) (%) (maf) (ft) Fontenelle , Flaming Gorge , Blue Mesa , Navajo , Lake Powell , Lake Mead , Lake Mohave Lake Havasu Totals * From October 1, 2007, to September 30, Table 2. Reservoir Conditions on October 1, 2008 (Metric Units) Reservoir Vacant Space Live Storage Water Elevation Percent of Capacity Change in Storage * Change in Elevation * (mcm) (mcm) (m) (%) (mcm) (m) Fontenelle , Flaming Gorge 896 3,730 1, Blue Mesa , Navajo 463 1,627 1, Lake Powell 12,102 17,896 1, , Lake Mead 17,105 14, Lake Mohave 277 1, Lake Havasu Totals 31,221 41, ,389 * From October 1, 2007, to September 30, Draft AOP October 21, 2008

12 WATER SUPPLY ASSUMPTIONS For 2009 operations, three reservoir unregulated inflow scenarios were developed and analyzed and are labeled as probable maximum, most probable, and probable minimum. The attached graphs show these inflow scenarios with associated release patterns and endof-month contents for each reservoir. There is considerable uncertainty associated with streamflow forecasts and reservoir operating plans made a year in advance. The National Weather Service s Colorado Basin River Forecast Center developed the inflow for the probable maximum (10 percent exceedance), most probable (50 percent exceedance), and probable minimum (90 percent exceedance) inflow scenarios in 2009 using the Ensemble Streamflow Prediction (ESP) model. The ESP model accounts for antecedent streamflows as well as current soil moisture levels with a continuous soil moisture accounting model known as the Sacramento Soil Moisture Accounting Model. The most probable unregulated inflow for Lake Powell in water year 2009 is maf (13,371 mcm), or 90 percent of average. The probable minimum unregulated inflow to Lake Powell in water year 2009 is 4.00 maf (4,934 mcm), or 33 percent of average. The probable maximum unregulated inflow is maf (22,203 mcm), or 149 percent of average. The three inflow scenarios for Lake Powell are shown in Tables 3 and 4. Inflows to the mainstream from Lake Powell to Lake Mead, Lake Mead to Lake Mohave, and Lake Mohave to Lake Havasu are forecasted using historic data over the five-year period of January 2003 through December 2007, inclusive. The last five years of historic data are being used to best represent most recent hydrologic conditions for operational forecasts. Most probable forecasted side inflows into each reach are the arithmetic mean of the five- year record. The probable maximum and probable minimum forecasts for the reach between Lake Powell and Lake Mead are the 10 percent exceedance and 90 percent exceedance, respectively, of the five-year record. The most probable side inflow into Lake Mead during water year 2009 is maf (1,148 mcm). The probable minimum side inflow into Lake Mead is maf (609 mcm). The probable maximum side inflow is maf (1,971 mcm). The monthly volumes of inflow resulting from these assumptions were input into Reclamation s monthly reservoir simulation model and used to plan reservoir operations for Starting with October 1, 2008, reservoir storage conditions, the monthly releases for each reservoir were adjusted until release and storage levels best accomplished project purposes and applicable operational objectives. Graphs of the projected 2009 inflows, releases, and storages for each hydrologic scenario are presented in Attachment I Draft AOP October 21, 2008

13 Table 3. Projected Unregulated Inflow into Lake Powell for Water Year 2009 (English Units: maf) 17 Time Period Probable Minimum Most Probable Probable Maximum 10/08 12/ /09 3/ /09 7/ /09 9/ /09 12/ WY CY Table 4. Projected Unregulated Inflow into Lake Powell for Water Year 2009 (Metric Units: mcm) Time Period Probable Minimum Most Probable Probable Maximum 10/08 12/ ,600 2,450 1/09 3/ ,740 2,160 4/09 7/09 2,650 8,870 15,550 8/09 9/ ,160 2,050 10/09 12/09 1,910 1,790 1,910 WY ,930 13,370 22,200 CY ,940 13,560 21, All values in Tables 3 and 4 are forecasted inflows with the exception of the values for 10/09-12/09. The values for this period are the average unregulated inflow from The calendar year totals in Tables 3 and 4 also reflect the average values for the 10/09-12/09 time period Draft AOP October 21, 2008

14 SUMMARY OF RESERVOIR OPERATIONS IN 2008 AND PROJECTED 2009 RESERVOIR OPERATIONS The operation regulation of the Colorado River reservoirs has had effects on some aquatic and riparian resources. Controlled releases from dams have modified temperature, sediment load, and flow patterns, resulting in increased productivity of some riparian and non-native introduced aquatic resources and the development of economically significant sport fisheries. However, these same releases have detrimental effects on endangered and other native species. Operating strategies designed to protect and enhance aquatic and riparian resources have been established after appropriate through the National Environmental Policy Act (NEPA) compliance at several locations in the Colorado River Basin. In the Upper Basin, public stakeholder work groups have been established at Fontenelle Dam, Flaming Gorge Dam, the Aspinall Unit, and Navajo Dam. These work groups provide a public forum for dissemination of information regarding ongoing and projected reservoir operations throughout the year and allow stakeholders the opportunity to provide information and feedback with respect to ongoing reservoir operations. The Glen Canyon Dam Adaptive Management Work Group (AMWG), a Federal Advisory Committee Act committee, was established in Since its inception, the AMWG has met regularly to analyze and make recommendations to the Secretary regarding research and monitoring programs in the Grand Canyon as well as experimental modifications to dam operations. 18 Modifications to planned operations may be made based on changes in forecasted conditions or other relevant factors. Consistent with the Upper Colorado River Endangered Fish Recovery Program (Upper Colorado Recovery Program), 19 the San Juan River Basin Recovery Implementation Program (San Juan Recovery Program), 20 Section 7 consultations under the Endangered Species Act (ESA), and other downstream concerns, modifications to monthly operation plans may be based on other factors in addition to changes in-stream flow forecasts. Decisions on spring peak releases and downstream habitat target flows may be made midway through the runoff season. Reclamation will conduct meetings with the U.S. Fish and Wildlife Service (Service), other Federal agencies, representatives of the Basin States, and with public stakeholder work groups to facilitate the discussions necessary to finalize site-specific operations plans. In 1995, Reclamation and the Service formed a partnership with other Federal, state, and local public agencies and private organizations to develop the Lower Colorado River Multi- Species Conservation Program (LCR MSCP). This program permits both non-federal and Federal parties to participate in and address ESA compliance requirements under Sections 7 and 10 of the ESA. In April 2005, the Secretary signed the Record of Decision (ROD) to begin implementation of the LCR MSCP. 21 Reclamation, in consultation and partnership with a Steering Committee made up of representatives from 56 participating entities, is the 18 Additional information on the AMWG can be found at 19 Additional information on the Upper Colorado Recovery Program can be found at 20 Additional information on the San Juan Recovery Program can be found at 21 Additional information on the LCR MSCP can be found at Draft AOP October 21, 2008

15 primary implementing agency. The LCR MSCP is currently meeting the goals outlined in the habitat conservation plan. The following paragraphs discuss the 2008 and most probable projected 2009 operation of each of the reservoirs with respect to applicable provisions of compacts, the Consolidated Decree, statutes, regulations, contracts, and instream flow needs for maintaining or improving aquatic and riparian resources where appropriate. Fontenelle Reservoir Hydrologic conditions in water year 2008 in the Upper Green River Basin were slightly below average when compared to the historic record for the reservoir. The April through July inflow to Fontenelle Reservoir during water year 2008 was maf (718 mcm), which was 68 percent of average. Though conditions were well above average in the rest of the Upper Colorado River Basin, the Upper Green River Basin was below average and was classified as continuing to be in drought. Inflow to Fontenelle Reservoir has been below average for nine consecutive years. Fontenelle Reservoir filled in 2008 and bypass releases were necessary in order to safely route the spring runoff. Inflow peaked at 6,225 cfs (176 cubic meters per second [cms]) on June 27, Releases from Fontenelle Reservoir increased from a baseflow of 700 cfs (19.8 cms) to powerplant capacity (approximately 1,700 cfs, [48 cms]) during the spring runoff period. Bypass releases up to 2,500 cfs (70.8 cms) were sustained for a total of 11 days in July, including ramping days. The resulting peak releases of 4,195 cfs (119 cms) occurred on July 10, The peak elevation of Fontenelle Reservoir during water year 2008 was 6,505.7 feet (1,982.9 meters) above sea level which occurred on July 8, This elevation is 0.3 feet (0.1 meters) below the spillway crest elevation. The most probable April through July inflow to Fontenelle Reservoir during water year 2009 is maf (945 mcm), or 89 percent of average. This volume far exceeds the maf (426 mcm) storage capacity of Fontenelle Reservoir. For this reason, the most probable and probable maximum inflow scenarios require releases during the spring that exceed the capacity of the powerplant to avoid uncontrolled spills from the reservoir. It is very likely that Fontenelle Reservoir will fill during water year In order to minimize high spring releases and to maximize downstream water resources and power production, the reservoir will most likely be drawn down to about elevation 6,468 feet (1,971 meters) by early April 2009, which is five feet (1.5 meters) above minimum power pool, and corresponds to a volume of maf (137 mcm) of live storage. Flaming Gorge Reservoir Inflow to Flaming Gorge Reservoir during water year 2008 was below average. Unregulated inflow in water year 2008 was maf (1,262 mcm), which is 59 percent of average. Flaming Gorge Reservoir did not fill during water year On October 1, 2007, the beginning of water year 2008, the reservoir elevation was 6,022.3 feet (1,835.6 meters). The reservoir elevation showed an overall decrease during water year 2008 with an ending water year (September 30, 2008) reservoir elevation of 6, feet (1, meters). The water year ending reservoir elevation was feet (5.72 meters) below the full pool elevation of Draft AOP October 21, 2008

16 ,040.0 feet (1,841.0 meters) which corresponds to an available storage space of maf (896 mcm). Reclamation operated Flaming Gorge Dam in compliance with the Flaming Gorge Record of Decision (Flaming Gorge ROD) in The hydrologic conditions during the spring of 2008 were designated as average. Reclamation convened the Flaming Gorge Technical Working Group (FGTWG) comprised of the Service, Western Area Power Administration (Western), and Reclamation personnel. The FGTWG proposed to Reclamation that the Green River measured at the Jensen, Utah, stream gauge gage be managed to maintain flows at or above 15,000 cfs (425 cms) for a minimum of five consecutive days during the peak flows of the Yampa River. The Yampa River Basin received significant amounts of moisture and the FGTWG agreed that if flows at Jensen, Utah, were at or above 18,600 cfs (526.4 cms) for at least 10 days, Reclamation should consider managing river flows to achieve the 18,600 cfs (526.4 cms) target at Jensen, Utah, for 14 days if reasonably possible. Releases from Flaming Gorge Reservoir were increased to powerplant capacity of 4,300 cfs (121.8 cms) on May 17, 2008, in anticipation of peak flows on the Yampa River. On June 6, 2008, as a result of releases from Flaming Gorge Dam and flows on the Yampa River, the flows in the Green River at Jensen reached 23,875 cfs (676 cms). Releases were maintained at powerplant capacity until June 15, 2008, when the flows in the Green River at Jensen dropped below 14,000 cfs (396 cms). Flows in the Green River at Jensen remained above 15,000 cfs (425 cms) from May 21, 2008, to June 14, 2008 (24 days), with 14 days of flows greater than 18,600 cfs (526.4 cms). The use of the bypass tubes was not required to meet these flow objectives. Releases from Flaming Gorge Reservoir were reduced by 500 cfs (14 cms) per day beginning on June 15, In June 2008, hydrologic conditions deteriorated from average to a moderately dry. Reclamation convened the FGTWG to develop a flow proposal for the Green River during the base flow period (August through February of the following year). The FGTWG proposed to Reclamation that flows in the Green River, during the base flow period, should fall within the average range, as described in the Flaming Ggorge Final Impact Statement for the Action Alternative. The purpose of this proposal was to better match the flow conditions that occurred during the spring peak when average targets were achieved. Additionally, the Upper Colorado River Endangered Species Recovery Program requested research flows of 1,500 cfs (42.48 cms) in the Green River below Flaming Gorge Dam during the base flow period through September 30, Releases reached 1,500 cfs (42.48 cms) on June 25, 2008, and were maintained at that the level through September 30, During water year 2009, Flaming Gorge Dam will continue to be operated in accordance with the Flaming Gorge ROD. High spring releases are scheduled to occur in 2009, timed with the Yampa River s spring runoff peak flow, followed by lower summer and autumn base flows. Under the most probable scenario, releases of 1,100 cfs (31.1 cms) will beginbegan on October 13, 2008, and will likely continue through February 28, Beginning March 1, 2009, releases wouldwill decrease to 800 cfs (22.65 cms) and willwould likely remain at that level until the beginning of the 2009 high spring peak release. Western is working with the Utah Department of Wildlife Resources to study effects downstream of a double-peak fluctuating flow pattern. Reclamation will be considering an operation Draft AOP October 21, 2008

17 regime that includes double peaks during the winter months of water year 2009 depending on water availability. The Upper ColoradoRiver Endangered Species Recovery Program, in coordination with Reclamation, the Service, and Western, is conducting studies associated with floodplain inundation. Such studies include: (1) improving connectivity of floodplain habitats, (2) identifying ways to improve entrainment of larval razorback suckers into floodplain habitats, (3) maintaining the river channel, (4) restoring natural variability of the river system, and (5) analyzing possibilities for meeting the goals of the Flow flow and Temperature temperature Rrecommendations for Endangered Fishes in the Green River downstream of Flaming Gorge Dam at lower peak flow levels where feasible. 22 Blue Mesa, Morrow Point, and Crystal Reservoirs (Aspinall Unit) Above average snowpack conditions prevailed in the Gunnison Basin during water year Snow measurement sites in the basin reported above average moisture throughout the winter and into the spring of The April through July unregulated runoff into Blue Mesa Reservoir in 2008 was maf (1,241 mcm), which was 140 percent of average. Water year 2008 unregulated inflow into Blue Mesa Reservoir was maf (1,633 mcm), which was 133 percent of average. Blue Mesa Reservoir came close to filling in 2008 reaching a peak elevation of 7, feet (2,289.6 meters) on July 31, 2008, 7.5 feet (2.3 meters) from full pool. Storage in Blue Mesa Reservoir decreasedincreased during water year 2008 by maf (45.64 mcm). Storage in Blue Mesa Reservoir on September 30, 2008, was maf (802 mcm), or 78 percent of capacity. Releases from Aspinall Unit reservoirs in 2008 were much above normal levels. Releases from the Aspinall Unit provided for a flow of 650 to 1,100 cfs (18.4 to 31.1 cms) from October 1, 2007, to January 9, 2008, in the Gunnison River through the Black Canyon (below the Gunnison Tunnel). On January 19, 2008, releases were increased to 1,800 cfs (51.0 cms) in response to above average forecasted inflow. Beginning the first week of March, Crystal Dam releases were decreased to accomplish planned maintenance activities for inspection of the stilling basin at Crystal Dam stilling basin and later in the month for rock removal from the stilling basin at Blue Mesa DamReservoir s stilling basin. During the month of March, flows ranged from a low of no flow (very short duration) up to 1,900 cfs (53.8 cms). Starting the first of April, after all maintenance activities were accomplished, Crystal Dam releases were increased to maximum powerplant capacity of 2,100 cfs (59.5 cms). Later in April, the releases were again increased and the river bypass valves were opened. Maximum bypass at Crystal Dam was realized on April 29, 2008, at 4,200 cfs (118.9 cms). Crystal Dam started to spill on May 21, 2008, and achieved a maximum release of 7,921 cfs (224 cms) on May 31, Water year 2008 powerplant bypasses were approximately maf (482 mcm) at Crystal Dam. These bypass releases occurred due to the large spring runoff and to a lesser extant extent due to maintenance activities during March. 22 Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Gorge Dam, September Draft AOP October 21, 2008

18 On August 16, 1995, Memorandum of Agreement (MOA) No R1760 was signed by Reclamation, the Service, and the Colorado Water Conservation Board. The purpose of the MOA was to provide water to the Redlands Fish Ladder, assure at least 300 cfs (8.5 cms) of flow in the 2-mile reach of the Gunnison River between the Redlands Fish Ladder and the confluence of the Gunnison and Colorado Rivers (2-mile reach), and to benefit Colorado River Basin endangered fish. This MOA was extended for an additional five years on June 30, A key provision of the MOA requires that the parties adopt a plan to share water shortages in dry years, when total storage at Blue Mesa Reservoir is projected to drop below 0.40 maf (493 mcm) by the end of calendar year However, the MOA was not renewed in To the extent possible, Reclamation will continue to meet the intent of the MOA to the degree that as it falls within the scope of normal operations and will also continue to coordinate with the Aspinall Working Group as part of the operational planning process. For water year 2009, the Aspinall Unit will be operated to conserve storage while meeting downstream delivery requirements, consistent with authorized project purposes. Under normal conditions, the minimum release objectives of the Aspinall Unit are to honor the delivery requirements of the Uncompahgre Valley Project, and other senior water rights downstream, to the extent possible to maintain a year round minimum flow of at least 300 cfs (8.5 cms) in the Gunnison River through the Black Canyon, and to the extent possible maintain a minimum flow of 300 cfs (8.5 cms) in the 2-mile reach below the Redlands Diversion Dam during the months of July through October. In dry years, the 300 cfs (8.5 cms) flow through the canyon and the 2-mile reach may be reduced. In 2009, under the most probable inflow conditions, flows through the Black Canyon of the Gunnison National Park will be above the 300 cfs (8.5 cms) minimum release objective during the summer months. Consideration shall be given to the trout fishery in the Black Canyon and Gunnison Gorge and recreational interests consistent with Pproject purposes. Releases during 2009 will be planned to minimize fluctuations in the daily and monthly flows in the Gunnison River below the Gunnison Tunnel diversion. Under the probable minimum inflow scenario, Blue Mesa Reservoir would not fill in Under the most probable and probable maximum inflow scenarios, Blue Mesa Reservoir is expected to fill in Navajo Reservoir Inflow to Navajo Reservoir in 2008 was above the 30-year average. Water year 2008 unregulated inflow was maf (1,649 mcm), or 120 percent of average. The April through July unregulated inflow into Navajo Reservoir in water year 2008 was maf (1,183 mcm), or 122 percent of average. Unregulated inflow to Navajo Reservoir has been below average for all water years from 2000 through 2007, except for 2005 which was 136 percent of average. Navajo Reservoir reached a peak water surface elevation of 6,066.8 feet (1,849.2 meters) on May 25, 2008, 18.2 feet (5.5 meters) from full pool. The water surface elevation at Navajo Reservoir on September 30, 2008, was 6,057.7 feet (1,846.4 meters), with reservoir storage at 78 percent of capacity Draft AOP October 21, 2008

19 The A final report titled, Flow Recommendations for the San Juan River (San Juan Flow Recommendations), which outlines flow recommendations for the San Juan River (San Juan Flow Recommendations) below Navajo Dam, was completed by the San Juan Recovery Program in May 1999 after a seven-year research period. 23 The purpose of the report was to provide flow recommendations for the San Juan River that promote the recovery of the endangered Colorado River pikeminnow and razorback sucker, maintain important habitat for these two species as well as the other native species, and provide information for the evaluation of continued water development in the basin. In 2006, Reclamation completed a NEPA process on the implementation of operations at Navajo Dam that meet the San Juan Flow Recommendations, or a reasonable alternative to them. The ROD for the Navajo Reservoir Operations Final EIS was signed by the Regional Director of Reclamation s Upper Colorado Region on July 31, The San Juan Flow Recommendations called for a 21-day spring peak release of 5,000 cfs (142 cms) from Navajo Reservoir in Due to a high inflow forecast received in February, a release of 3,000 cfs (854.9 cms) began on February 12, The decision was made to begin releases a couple weeks earlier than the March 1 st minimum release date identified in the San Juan Flow Recommendations to avoid a potential spill and to avoid triggering mandatory inspections of the outlet works that are required at higher releases. Another increase in the inflow forecast for March led to the decision to release 4,000 cfs (1134 cms) beginning March 10, This release continued until April 7, 2008, when the release was reduced in order to perform a required inspection on the 72-inch main outlet pipe. The April inflow forecast led to the decision to continue releases at 2,200 cfs (62.53 cms). A further decrease in releases to 1,000 cfs (28.43 cms) occurred on May 12, 2008, due to a further decrease in the May inflow forecast. The spring peak release began on May 19, 2008, with a release of 2,000 cfs (56.86 cms) ramping up to a release rate of 5,000 cfs (142 cms) reached on May 28, 2008, and maintained through June 18, The rampdown began on June 19, 2008 and the base summer release rate of 500 cfs (14.12 cms) was implemented on July 2, In 2007, a two-year agreement, Recommendations for Administration and Operation of the San Juan River, was developed amongst major users to limit their water use to the rates/volumes indicated in the agreement. 24 for the years The agreement was similar to the agreements that were developed in 2003, 2004, 2005, and Ten major water users (the Jicarilla Apache and Navajo Nations, Hammond Conservancy District, Public Service Company of New Mexico, City of Farmington, Arizona Public Service Company, BHP-Billiton, Bloomfield Irrigation District, Farmers Mutual Ditch, and Jewett Valley Ditch) endorsed the recommendations. The recommendations included limitations on diversions for , criteria for determining a shortage, and shortage-sharing requirements in the event of a water supply shortfall, including sharing of shortages between the water users and the flow demands for endangered fish habitat. In addition to the ten major water users, the New Mexico Interstate Stream Commission, the Bureau of Indian Affairs, the Service, and the San Juan Recovery 23 Flow Recommendations for the San Juan River, May Recommendations for San Juan River Operations and Administration for 2007 and 2008, December 15, Draft AOP October 21, 2008

20 Program all provided input to the recommendations. The recommendations were acknowledged by Reclamation and the New Mexico State Engineer for reservoir operation and river administration purposes. A new two-year agreement, similar to past years, is expected to be developed for 2009 and During water year 2009, Navajo Reservoir will be operated in accordance with the Navajo Reservoir Operations ROD. Navajo Reservoir storage levels are expected to be near average in 2009 under the most probable inflow scenario. Releases from the reservoir will likely remain at a 500 cfs (14 cms) base release through the winter. Under the most probable inflow condition in 2009, a 21-day spring peak release of 5,000 cfs (142 cms), as described in the San Juan Flow Recommendations, is likely to occur. Lake Powell Reservoir storage in Lake Powell increased significantly in water year On October 1, 2007, the beginning of water year 2008, reservoir storage in Lake Powell was 49 percent of capacity or maf (14,720 mcm). As a result of inflows to Lake Powell during water year 2008 that were above normal (102 percent of average), Lake Powell storage increased during water year 2008 by 2.58 maf (3,180 mcm) and ended the water year 2008 (September 30, 2008) at 60 percent of capacity, or maf (17,920 mcm). Due to low reservoir storage at Lake Powell on January 1, 2008, and storage in Lake Powell being less than Lake Mead, and in concurrence with Section 6.B (Upper Elevation Balancing Tier) of the Interim Guidelines, the annual release volume from Glen Canyon Dam in 2008 was initially scheduled to be 8.23 maf (10,0150 mcm). In April, consistent with Section 6.B.3 of the Interim Guidelines, However, the April 24-month study forecasted inflows to Lake Powell projected the September 30, 2008, Lake Powell elevation to be above 3,636 feet (1,108.2 meters) (the equalization level for water year 2008), based on the April 1 st final inflow forecast. Consistent with Section 6.B.3 of the Interim Guidelines, this which triggered Section 6.A (Equalization Tier) of the Interim Guidelines to govern the operation of Glen Canyon Dam for the remainder of water year Under the Equalization Tier, Tthe annual release volume during water year 2008 from Glen Canyon Dam was maf (11,070 mcm). April through July unregulated inflow to Lake Powell in water year 2008 was maf (10,990 mcm) or 112 percent of average. Lake Powell reached a seasonal peak elevation of 3,633.7 feet (1,107.6 meters), 66.3 feet (20.2 meters) from full pool, on July 16, On September 30, 2008, the water surface elevation of Lake Powell was 3,626.9 feet (1,105.5 meters), 73.1 feet (22.3 meters) from full pool. In December 2007, Reclamation proposed a Spring 2008 high flow test as part of experimental releases from Glen Canyon Dam. This proposal was the result of information gathered through scientific monitoring and research activities and discussions within the Glen Canyon Dam Adaptive Management Program. The proposal also included steady flows in September and October to be implemented each year during the next five years ( ) and ROD flows in the other months (November through August). ESA and NEPA compliance for the proposed high flow test and five-year period of steady flows was completed. A Final Biological Opinion on the Operation of Glen Canyon Dam was issued Draft AOP October 21, 2008

21 on February 27, 2008, and a final Environmental Assessment (EA) and Finding of No Significant Impact were issued on February 29, The high flow test was initiated on March 5, 2008, and completed on March 9, During the high flow experiment, Reclamation released water through Glen Canyon Dam s powerplant and bypass tubes to a maximum amount of 41,500 cfs (1,180 cms) for 60 hours. As a result of the high flow test, the elevation of Lake Powell dropped by approximately 2.3 feet (0.70 meters). However, the annual volume of water released from Lake Powell for water year 2008 was not modified as a result of the high flow experiment. A test of steady flows (steady daily releases), as described in the EA, was conducted during September and October in The steady flow test will be repeated through Annual releases from Lake Powell during water year 2009 will be made consistent with Section 6.B (Upper Elevation Balancing Tier) of the Interim Guidelines. Consistent with Section 6.B.1 of the Interim Guidelines, the water year release from Lake Powell in 2009 will be 8.23 maf (10,150 mcm) unless provisions in Section 6.B.3 occur. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2009, Lake Powell elevation to be greater than elevation 3,639.0 feet (1,109 meters), Section 6.A (Equalization Tier) of the Interim Guidelines will govern the release of water from Lake Powell for the remainder of water year 2009 (through September 2009). The distribution of release volumes throughout water year 2009 will be consistent with the 1996 ROD and subsequent environmental compliance documents. Under the minimum probable inflow scenario, the Upper Elevation Balancing Tier would govern throughout water year 2009 and the annual release volume from Lake Powell would be 8.23 maf (10,150 mcm). The projected September 30, 2009, elevation and reservoir storage would be 3,594.5 feet (1,095.6 meters) and maf (13,850 mcm), respectively. Under the most probable and maximum probable inflow scenarios, the Upper Elevation Balancing Tier would govern through April In April 2009, however, the projected September 30, 2009, elevation of Lake Powell under the most probable and maximum probable inflow scenarios would likely trigger the Equalization Tier to govern the annual release volume for the remainder of water year Under the most probable inflow scenario the projected annual release volume would be maf (11,350 mcm). The projected September 30, 2009, elevation and reservoir storage would be 3,632.0 feet (1,107.0 meters) and maf (18,590 mcm), respectively. Under the maximum probable inflow scenario the projected annual release volume would be maf (17,160 mcm). The projected September 30, 2009, elevation and reservoir storage would be 3,651.7 feet (1,113.0 meters) and maf (21,490 mcm), respectively. In 2009, scheduled maintenance activities at Glen Canyon Dam powerplant will require that one or more of the eight generating units periodically be offline. Coordination between Reclamation offices in Salt Lake City, Utah, and Page, Arizona, will take place in the scheduling of maintenance activities to minimize impacts to operations throughout the water year including potential experimental releases. Because of less than full storage conditions in Lake Powell resulting from drought in the Colorado River Basin, releases for dam safety purposes are highly unlikely in If Draft AOP October 21, 2008

22 implemented, releases greater than powerplant capacity would be made consistent with the 1956 Colorado River Storage Project Act, the Colorado River Basin Project Act, and to the extent practicable, the recommendations made pursuant to the 1992 Grand Canyon Protection Act. Reservoir releases in excess of powerplant capacity required for dam safety purposes during high reservoir conditions may be used to accomplish the objectives of the beach/habitat-building flow according to the terms contained in the Glen Canyon Dam ROD and as published in the Glen Canyon Dam Operating Criteria (62 Federal Register 9447, March 3, 1997). Daily and hourly releases in 2009 will be made according to the parameters of the 1996 ROD for the Glen Canyon Dam Final Environmental Impact Statement (GCDFEIS) and the Glen Canyon Dam Operating Criteria, as shown in Table 5. Exceptions to these parameters may be made during power system emergencies, during experimental releases, or for purposes of humanitarian search and rescue. Table 5. Glen Canyon Dam Release Restrictions (Glen Canyon Dam Operating Criteria) Parameter (cfs) (cms) Conditions Maximum Flow 25 25, Minimum Flow 5, :00 p.m. to 7:00 a.m. 8, :00 a.m. to 7:00 p.m. Ramp Rates Ascending 4, per hour Descending 1, per hour Daily Fluctuations 26 5,000 / 8, / Releases from Lake Powell in water year 2009 will continue to reflect consideration of the uses and purposes identified in the authorizing legislation for Glen Canyon Dam. Powerplant releases will reflect criteria based on the findings, conclusions, and recommendations made in the 1996 ROD for the GCDFEIS pursuant to the Grand Canyon Protection Act of 1992 and appropriate NEPA documentation regarding experimental flows. Consistent with the GCDFEIS and the 1996 ROD, projected monthly releases under the most probable, minimum probable, and maximum probable inflow scenario, for water year 2009, are displayed in Table 6 and Table May be exceeded during beach/habitat-building flows, habitat maintenance flows, or when necessary to manage above average hydrologic conditions. 26 Daily fluctuations limit is 5,000 cfs (142 cms) for months with release volumes less than maf (740 mcm); 6,000 cfs (170 cms) for monthly release volumes of to maf (740 to 990 mcm); and 8,000 cfs (227 cms) for monthly release volumes over maf (990 mcm) Draft AOP October 21, 2008

23 Table 6. Projected Monthly Releases from Lake Powell in Water Year 2009 Under Most Probable Inflow Conditions (English Units) 27 Month Most Probable Inflow Scenario Projected Monthly Release Volume (maf) Minimum Probable Inflow Scenario Projected Monthly Release Volume (maf) Maximum Probable Inflow Scenario Projected Monthly Release Volume (maf) October November December January February March April May June July August September Water Year 2009 Total Table 7. Projected Monthly Releases from Lake Powell in Water Year 2009 Under Most Probable Inflow Conditions (Metric Units) Month Most Probable Inflow Scenario Projected Monthly Release Volume (mcm) Minimum Probable Inflow Scenario Projected Monthly Release Volume (mcm) Maximum Probable Inflow Scenario Projected Monthly Release Volume (mcm) October November December January February ,233 March ,896 April ,834 May ,896 June , ,834 July ,196 1,026 1,896 August ,196 1,025 1,896 September ,079 Water Year 2009 Total 11,342 10,151 17,162 The ten-year total flow of the Colorado River at Lee Ferry 28 for water years 1999 through 2008 is 88.7 maf (109,400 mcm). This total is computed as the sum of the flow of the 27 Modifications to projected monthly releases from Lake Powell would be made based on changes in forecasted conditions or other relevant factors Draft AOP October 21, 2008

24 Colorado River at Lees Ferry, Arizona, and the Paria River at Lees Ferry, Arizona, surfacewater discharge stations which are operated and maintained by the United States Geological Survey. Lake Mead For calendar year 2008, the ICS Surplus Condition was the criterion governing the operation of Lake Mead in accordance with Article III(3)(b) of the Operating Criteria, Article II(B)(2) of the Consolidated Decree, and Section 2.B.5 of the Interim Guidelines. A volume of maf (1,850 mcm) of water was scheduled for delivery to Mexico in accordance with Article 15 of the 1944 United States-Mexico Treaty and Minutes No. 242 and 310 of the IBWC. Lake Mead began water year 2008 on October 1, 2007, at elevation 1, feet (338.7 meters), with maf (15,419 mcm) in storage, which is 48 percent of the conservation capacity of maf (31,923 mcm). Lake Mead s elevation increased to an elevation of 1, feet (340.4 meters) by the end of February After February 2008, Lake Mead steadily declined. The September 30, 2008, end of water year elevation at Lake Mead was 1, feet (337.0 meters), with maf (14,814 mcm) in storage (46 percent of capacity). The total release from Lake Mead through Hoover Dam during water year 2008 was maf (11,756 mcm). The total release from Lake Mead through Hoover Dam during calendar year 2008 is projected to be maf (11,719 mcm). Consumptive use from Lake Mead during calendar year 2008 resulting from diversions for Nevada above Hoover Dam is projected to be maf (347.8 mcm). The total inflow into Lake Mead is a combination of water released from Glen Canyon Dam plus inflows in the reach between Glen Canyon and Hoover Dams. In water year 2008, inflow into Lake Mead was maf (12,204 mcm). For water year 2009, under the most probable assumptions, total inflow into Lake Mead is anticipated to be maf (12,495 mcm). Under the most probable inflow conditions during water year 2009, Lake Mead will be at its maximum elevation of 1, feet (339.6 meters), with maf (15,789 mcm) in storage, at the end of February Lake Mead will likely decline during water year 2009 to reach its minimum elevation of approximately 1, feet (336.7 meters), with approximately maf (14,703 mcm) in storage, at the end of July June Based on the August Month Study, Lake Mead s elevation on January 1, 2009, is projected to be 1, feet (338.5 meters). In accordance with Section 2.B.5 of the Interim Guidelines, the ICS Surplus Condition will govern the releases from Lake Mead in calendar year Releases from Lake Mead through Hoover Dam for water year and calendar year 2009 are anticipated to be approximately the same as 2008 releases. Lakes Mohave and Havasu 28 A point in the mainstream of the Colorado River one mile below the mouth of the Paria River Draft AOP October 21, 2008

25 At the beginning of water year 2008, Lake Mohave was at an elevation of feet (194.2 meters), with an active storage of maf (1,906 mcm). The water level of Lake Mohave was regulated between elevation feet (193.3 meters) and feet (196.3 meters) throughout the water year, ending at an elevation of feet (194.7 meters) with maf (1,955 mcm) in storage. The total release from Lake Mohave through Davis Dam for water year 2008 was maf (11,355 mcm) for downstream water use requirements. The calendar year 2008 total release is projected to be maf (11,368 mcm). For water year and calendar year 2009, Davis Dam is projected to release approximately the same amount of water as in The water level in Lake Mohave will be regulated between an elevation of approximately 633 feet (193 meters) and 645 feet (197 meters). Lake Havasu started water year 2008 at an elevation of feet (136.5 meters) with maf (710.5 mcm) in storage. The water level of Lake Havasu was regulated between elevation feet (136.1 meters) and feet (136.8 meters), throughout the water year, ending at an elevation of feet (136.6 meters), with maf (720 mcm) in storage. During water year 2008, maf (8,254 mcm) were released from Parker Dam. The calendar year 2008 total release is projected to be maf (8,395 mcm). Diversions from Lake Havasu during calendar year 2008 by the Central Arizona Project (CAP) and MWD are projected to be maf (1,856 mcm) and maf (1,039 mcm), respectively. For water year 2009, Parker Dam is expected to release approximately the same amount of water as in water year Diversions from Lake Havasu in calendar year 2009 by CAP and MWD are projected to be maf (1,867 mcm) and maf (1,028 mcm), respectively. Lakes Mohave and Havasu are scheduled to be drawn down in the late summer and fall months to provide storage space for local storm runoff and will be filled in the winter to meet higher summer water needs. This drawdown will also correspond with normal maintenance at both Davis and Parker powerplants which is scheduled for September through February. At Davis Dam, a major overhaul of Unit No. 2 began on October 1, 2007, and the unit was returned to service on March 17, This overhaul included removal and maintenance of the fixed wheel gate and hydraulic cylinder, as well as testing the generator windings. Rehabilitation of the fixed wheel gate of Unit 1 is tentatively scheduled for water year 2009began on October 6, 2008, with an anticipated return to service of March 19, At Parker Dam, a major turbine overhaul of Unit 1 began on September 7, 2007, and it the unit was returned to service on August 15, A major turbine overhaul of Unit 2 is scheduled began on for September 2, 2008, through with an anticipated return to service of February 28, Bill Williams River Runoff and precipitation events during December 2007, and January and February 2008, contributed to tributary inflows that increased Lake Alamo s storage by maf (61.67 mcm) by mid March Tributary monthly inflows into Lake Alamo were below average Draft AOP October 21, 2008

26 except for January during water year Abnormally dry to moderate drought conditions persisted for water year 2008 throughout in far western and southern Arizona, including the Bill Williams River watershed. Tributary inflow from the Bill Williams River into the mainstream of the Colorado River totaled maf (35.77 mcm) for water year 2008, approximately 28 percent of the long-term average. Releases in water year 2008 from the United States Army Corp of Engineers (USACE s) Alamo Dam were coordinated with the Service and the Bill Williams River Corridor Steering Committee (BWRCSC) to maintain riparian habitat established in water year 2005 and Alamo Lake elevation was approximately 1, feet ( meters) after October 1, 2007, and increased to elevation 1, feet ( meters) by mid March A storage volume of maf (2.47 mcm), equivalent to the storage between approximately elevations 1,125.8 feet (343.1 meters) and 1,125.4 feet (343.0 meters), was released on March 31, The purpose of the release was to maintain downstream riparian habitat. The March 31, 2008, release from Alamo Dam increased from approximately 40 cfs (1 cms) to approximately 2,000 cfs (56.6 cms) for a 14-hour period, tapering to approximately 40 cfs (1 cms) on the same day. Data collection associated with Alamo Dam releases supports ongoing studies conducted by the Bill Williams Steering Committee BWRCSC. The BWRCSC Bill Williams Steering Committee is chaired by the Service and is comprised of other stakeholders, including, but not limited to, Reclamation, the USACE, the Bureau of Land Management, and other governmental and nongovernmental organizations. Senator Wash and Laguna Reservoirs Operations at Senator Wash Reservoir allow regulation of water deliveries to United States water users upstream and downstream of Imperial Dam and Mexican water users downstream of Imperial Dam. The reservoir is utilized as an off-stream storage facility to meet downstream water demands and to conserve water for future uses in the United States and the scheduled uses of Mexico in accordance with the 1944 United States-Mexico Water Treaty obligations. Senator Wash Reservoir is the only major storage facility below Parker Dam (approximately 142 river miles downstream) and has a storage capacity of maf (17.27 mcm) at full pool elevation of feet (76.5 meters). Operational objectives are to store excess flows from the river caused by water user cutbacks and side wash inflows due to rain. Stored waters are utilized to meet the United States and Mexico s water demandsdemands of the United States and the delivery obligation to Mexico. Since 1992, elevation restrictions have been placed on Senator Wash Reservoir due to potential piping and liquefaction of foundation and embankment materials at West Squaw Lake Dike and Senator Wash Dam. Currently, Senator Wash Reservoir is restricted to an elevation of feet (73.2 meters) with maf (11.10 mcm) of storage, a loss of about maf (6.167 mcm) of storage from its original capacity. Senator Wash Reservoir elevation must not exceed an elevation of feet (72.5 meters) for more than 10 consecutive days. This reservoir restriction is expected to continue in Laguna Reservoir is a regulating storage facility located approximately five river miles downstream of Imperial Dam. Operational objectives are similar to those for Senator Wash Reservoir and the reservoir is primarily used to capture sluicing flows from Imperial Dam Draft AOP October 21, 2008

27 The storage capability of Laguna Reservoir has diminished from about 1,500 acre-feet (1.850 mcm) to approximately 400 acre-feet (0.493 mcm) due to sediment accumulation and vegetation growth. Sediment accumulation in the reservoir has occurred primarily due to flood releases that occurred in 1983 and 1984, and flood control or space building releases that occurred between 1985 and 1988 and from 1997 through Imperial Dam Imperial Dam is the last diversion dam on the Colorado River for United States water users. From the head works at Imperial Dam, the diversions of flows for the United States and Mexico s water users occur into the All-American Canal on the California side, and into the Gila Gravity Main Canal on the Arizona side of the dam. These diversions supply all the irrigation districts in the Yuma area, in Wellton-Mohawk, in the Imperial and Coachella Valleys, and through Siphon Drop and Pilot Knob to the Northerly International Boundary (NIB) for diversion at Morelos Dam to the Mexicali Valley in Mexico. The diversions also supply much of the domestic water needs in the Yuma area. Flows arriving at Imperial Dam for calendar year 2008 are projected to be maf (6,993 mcm). The flows arriving at Imperial Dam for calendar year 2009 are projected to be approximately the same as calendar year Gila River Flows Although drought conditions eased for central Arizona, drought conditions persisted for water year 2008 throughout in other parts of the Lower Basin and the southwestern United States. Abnormally dry to moderate drought conditions persisted throughout in far western and southern Arizona, southern California, and southern Nevada. However, because of above average snowpack onin the Gila, Salt, and Verde River watersheds, the Gila River Basin experienced 110 percent of average precipitation for water year During water year 2008 no tributary inflow from the Gila River reached the mainstream of the Colorado River. Additional Regulatory Storage (Drop 2 Storage Reservoir) In 2005, Reclamation completed a study 29 that evaluated the needs and developed options for additional water storage facilities on the mainstream of the Colorado River below Parker Dam. The study, developed in cooperation with Imperial Irrigation District (IID), Coachella Valley Water District (CVWD), San Diego County Water Authority (SDCWA), and MWD, recommended the construction of a small reservoir near the All-American Canal in Imperial County, California, as the best option. The purpose of the planned maf (9.868 mcm) Drop 2 Storage Reservoir is to capture extra water in the system, especially during storm events. The reservoir will make up for the loss of water storage at Senator Wash due to the operational restrictions and provide additional regulatory storage, allowing for more efficient management of water below Parker Dam. 29 Preliminary Study of Lower Colorado River Water Storage Alternatives, February 21, Draft AOP October 21, 2008

28 Final design of the Drop 2 Storage Reservoir was completed in the spring of The construction contract is scheduled to bewas awarded to Ames-Coffman Joint Venture onin August 30, 2008 and construction of the first phase of the project is scheduled to start began in September Construction is scheduled to be completed in the fall of Yuma Desalting Plant In 1974, the Colorado River Basin Salinity Control Act (Public Law ) authorized the federal government to construct the YDP to desalt the drainage flows from the Wellton- Mohawk Division of the Gila Project.The Yuma Desalting Plant (YDP) was authorized and constructed to reduce the salinity of drain water from the Wellton-Mohawk Division of the Gila Project, This would allowing the treated water to be delivered to Mexico as part of its 1.5 maf (1,850 mcm) 1944 United States-Mexico Water Treaty allotment. The YDP operated at one-third capacity from May 1992 through January Gila River flood flows occurring during 1993 damaged the concrete lining of sections of the Main Outlet Drain Extension (MODE), which carries feed water to the YDP. In January 1993, Reclamation placed the YDP into ready reserve status, and the YDP has continued to be maintained in that status. To date, the United States has met salinity requirements, established in IBWC Minute 242 of the 1944 United States-Mexico Water Treaty, through use of a the Main Outlet Drain (MOD)bypass canal to bypass Wellton-Mohawk drain water to the Cienega de Santa Clara, a wetland of approximately 40,000 acres (16,200 hectares) of open water and vegetation that is within a Biosphere Reserve in Mexico. In calendar year 2008, the amount of water discharged through the (MOD)bypass canal is projected anticipated to be maf (135.7 mcm), measured at the Southerly International Boundary (SIB), at an approximate concentration of total dissolved solids of 2,430 parts per million (ppm). Due to the ongoing drought in the Southwest, there is concern about continuing to discharge water through the bypass canal, as such water is not credited toward the United States obligation to deliver water to Mexico pursuant to the 1944 United States-Mexico Water TreatyMOD. Reclamation initiated the Bypass Flow Consultation Process a public process in 2005 to identify, analyze, and evaluate methods to replace or recover the water discharged through the bypass canal MOD. A report is being prepared and is anticipated to be completed by the end of As part of the public process, Reclamation completed a demonstration run of the YDP in 2007, operating the plant at 10 percent capacity for three months. By the conclusion of the three-month run, 0.004,349 mafacre-feet (5.364 mcm) had been delivered to the Colorado River and included in water deliveries to Mexico, preserving an equivalent volume in Colorado River system storage. The plant produced 0.002,632 mafacre-feet (3.247 mcm) of product water which was blended with 0.001,717 mafacre-feet (2.118 mcm) of untreated bypass flow water prior to discharge into the Colorado River. In early 2008, the Lower Division States formed a work group was formed to examine reactivation of the YDP. A proposed pilot project for operation of the YDP (YDP Pilot Project) is being considered to begin in 2009 to gather additional cost and operational data as well as data to assist in defining future modifications to further the public process. as a means to recover a portion of the bypass flows. Work group members include: the Arizona Department of Water Resources (ADWR), the Central Arizona Water Conservation Draft AOP October 21, 2008

29 DistrictCAWCD, MWD, and SNWA have expressed interest in providing additional funding for the YDP Pilot Project. The funding entities would receive System Efficiency ICS credits in exchange for that funding. If the proposed YDP Pilot Project is implemented, it is anticipated that approximately maf (36.51 mcm) of water would be released to the Colorado River for delivery to Mexico, conserving an equivalent amount of water in Lake Mead. Reclamation anticipates the Bypass Flow Public Consultation Process will conclude after the YDP Pilot Project and appropriate reports are completed. the City of Yuma, Environmental Defense Fund, MWD, SNWA, the Colorado River Board of California, Reclamation, and the Yuma County Water Users Association. Reclamation supports this work group with information and analysis. Intentionally Created Surplus The Interim Guidelines included the adoption of the ICS mechanism that among other things encourages the efficient use and management of Colorado River water in the Lower Basin. ICS may be created through several types of activities that include improvements in system efficiency, extraordinary conservation, tributary conservation, and the importation of non- Colorado River System water into the Colorado River mainstream. Several implementing agreements 30 were executed concurrent with the issuance of the ROD for the Interim Guidelines. ICS credits may be created and delivered in 2009 pursuant to the Interim Guidelines and the implementing agreements. Demonstration Program. In 2006, Reclamation implemented an ICS Demonstration Program in the Lower Basin. This program allowed Colorado River water entitlement holders to undertake extraordinary conservation activities in 2006 and 2007 to reduce their approved annual consumptive use of Colorado River water and account for that conserved water in Lake Mead. Reclamation entered into an agreement with MWD for the creation of ICS credits in calendar year 2006 and In calendar year 2006, MWD created maf (61.67 mcm) of ICS credits. In calendar year 2008, MWD is anticipated to recover up to maf (56.74 mcm) the balance of its ICS credits created under the ICS Demonstration Program. If MWD has not recovered all of its Demonstration Program ICS credits during calendar year 2008, MWD may request delivery of those credits during In calendar year 2007, IID planned to create maf (1.234 mcm) of ICS credits under the program. 8 Pursuant to the IID ICS agreement, the conserved water was applied to reduce its 2007 IOPP overrun. 30 Delivery Agreement between the United States and IID; Delivery Agreement between the United States and MWD; Delivery Agreement between the United States, SNWA and the CRCN; Lower Colorado River Basin Intentionally Created Surplus Forbearance Agreement among the Arizona Department of Water Resources, SNWA, CRCN, the Palo Verde Irrigation District (PVID), IID, CVWD, MWD, and the City of Needles; and the California Agreement for the Creation and Delivery of Extraordinary Conservation Intentionally Created Surplus among the PVID, IID, CVWD, MWD, and the City of Needles. 31 Agreement between Reclamation and MWD to Implement a Demonstration Program to Create Intentionally Created Surplus Water, May 18, Draft AOP October 21, 2008

30 System Efficiency ICS. Reclamation, the Colorado River Commission of Nevada (CRCN), and SNWA signed a funding agreement for the construction of the Drop 2 Storage Reservoir on December 13, In exchange for project funding of $172 million, the agreement provides for SNWA to receive maf (740.1 mcm) of ICS credits at an annual maximum delivery rate of maf (49.34 mcm) from 2011 until the year MWD and CAWCD became parties to the Funding Agreement in May, In exchange for a contribution of 1/6 th of the project funding amount, MWD and CAWCD each received maf (123.3 mcm) of SNWA s ICS credits with a corresponding reduction in SNWA s ICS credits to maf (493.4 mcm). In the event that project costs exceed $172 million but are less than $206 million, SNWA would receive an additional ICS credit of 1 acre-foot for each $600 of additional funding provided. In calendar year 2008, MWD is anticipated to take delivery of maf (41.94 mcm) of System Efficiency ICS credits created from the Drop 2 Storage Reservoir project. In calendar year 2009, MWD may request delivery of up to maf (41.94 mcm) of System Efficiency ICS credits created from the Drop 2 Storage Reservoir project. Extraordinary Conservation ICS. MWD may create Extraordinary Conservation ICS in Tributary Conservation ICS. Upon approval by the Secretary of an ICS creation plan, SNWA anticipates creating and taking delivery of Tributary Conservation ICS credits from projects on the Muddy and Virgin Rivers. SNWA anticipates creating and taking delivery of maf (19.74 mcm) of Tributary Conservation ICS credits in 2008, and maf (37.00 mcm) in Any Tributary Conservation ICS credits created in a year but not delivered in that year would be converted to Extraordinary Conservation ICS at the beginning of the following year. System Conservation of Colorado River Water Demonstration Program In 2006, Reclamation implemented the System Conservation of Colorado River Water Demonstration Program (SC Demonstration Program) in the Lower Basin Division States which allows entitlement holders to participate in voluntary conservation to conserve a portion of their approved annual consumptive use of Colorado River water in exchange for appropriate compensation provided by Reclamation. Reclamation extended the SC Demonstration Program through December 31, The water conserved (SC Water) is retained in Lake Mead to assist in providing an interim, supplemental source of water to replace the drainage water from the WMIDDWellton-Mohawk Irrigation and Drainage District that is bypassed to the Cienega de Santa Clara and the reject stream from operation of the YDPYuma Desalting Plant. In calendar year 2008, approximately maf ( mcm) of SC Water is anticipated to be created by YMIDDYuma Mesa Irrigation and Drainage District (YMIDD) and retained in Lake Mead. 10 In calendar year 2009, approximately maf (4.317 mcm) of SC Water is projected to be created by YMIDD and retained in Lake Mead. 11 Delivery of Water to Mexico Draft AOP October 21, 2008

31 Total delivery to Mexico for calendar year 2008 is projected to be approximately maf (1,895 mcm), resulting in excess flows of approximately maf (44.41 mcm). The excess flows in 2008 resulted from a combination of rejected water from water users after rain storms, inflows into the Colorado River below Parker Dam, and spills from irrigation facilities below Imperial Dam to the river. Delivery to Mexico pursuant to the 1944 United States-Mexico Water Treaty is anticipated to be maf (1,850 mcm) in calendar year Excess flows arriving at the NIB are anticipated to be maf (65.37 mcm) in calendar year Excess flows result from a combination of factors, including water ordered but not delivered to United States users downstream of Parker Dam, inflows into the Colorado River below Parker Dam, and spills from irrigation facilities below Imperial Dam. Of the totaldelivery to Mexico in calendar year 2008, approximately maf (1,690 mcm) is projected to be delivered at the NIB and approximately maf (154.2 mcm) is projected to be delivered at the Southerly International Boundary (SIB)., and Aapproximately maf (6.167 mcm) will be diverted from Lake Havasu and delivered through MWD, SDCWA, and the Otay Water District s respective distribution system facilities to Tijuana, Baja California at the request of the Mexican section of the IBWC.. Of the delivery to the SIB in calendar year 2008, approximately maf (86.34 mcm) is projected to be delivered from the Yuma Project Main Drain and approximately maf (67.8 mcm) is expected to be delivered by the Protective and Regulatory Pumping Unit (Minute 242 wells). In calendar year 2009, it is anticipated that a volume of maf will be delivered to Mexico,Pursuant to the 1944 United States-Mexico Water Treaty, a volume of maf (1,850 mcm) will be available to be scheduled for delivery to Mexico in calendar year 2009, of which maf (172.7 mcm) is projected to be delivered at the SIB. In accordance with Minute No. 310 and the Following execution and approval of a new IBWC minute and amendment of the Emergency Delivery Agreement 32, up to maf (6.167 mcm) may be delivered for Tijuana through MWD, SDCWA, and the Otay Water District s respective distribution system facilities in California. The remainder of the maf (1,850 mcm) Mexico s available water will be delivered at NIB. Drainage flows to the Colorado River from the Yuma Mesa Conduit (YMC) and South Gila Conduit are projected to be maf (51.8 mcm) and maf (80.18 mcm), respectively, for calendar year This water is available for delivery at the NIB in satisfaction of the 1944 United States-Mexico Water Treaty. Of the total flow in the YMC, groundwater pumped by Reclamation under permit from ADWR to replace water bypassed to the Cienega through the bypass canal (MOD), is projected to be between to maf 32 The Agreement for Temporary Emergency Delivery of a Portion of the Mexican Treaty Waters of the Colorado River to the International Boundary in the Vicinity of Tijuana, Baja California, Mexico, and for Operation of the Facilities in the United States, applicable through November 9, It is anticipated that this agreement will be amended by the end of calendar year Draft AOP October 21, 2008

32 (22.20 to mcm) during calendar year In 2009, up to maf (30.84 mcm) of groundwater is projected to be pumped under this permit. 33 As stated in Minute 242, the maximum allowable salinity differential is 145 ppm by the United States measurement or count and 151 ppm by the Mexican count. The salinity differential for calendar year 2008 is projected to be 143 ppm by the United States count. Mexico has identified four critical months, October through January, regarding improving the quality of water delivered at the SIB. As a matter of comity, the United States has agreed to reduce the salinity of water delivered at SIB during this period. To accomplish the reduction in salinity, the United States constructed a diversion channel to bypass up to maf (9.868 mcm) of Yuma Valley drainage water during the four critical months identified by Mexico. This water will be replaced by better quality water from the Minute 242 well field to reduce the salinity at SIB. Reclamation anticipates bypassing approximately maf (1.233 mcm) in calendar year 2008 to the diversion channel for salinity control and up to maf (9.868 mcm) in calendar year DETERMINATIONS The AOP provides guidance regarding reservoir storage and release conditions during the upcoming year, based upon Congressionally mandated and authorized storage, release, and delivery criteria and determinations. After meeting these criteria and determinations, specific reservoir releases may be modified within these requirements as forecasted inflows change in response to climatic variability and to provide additional benefits coincident to the projects multiple purposes. Upper Basin Reservoirs Releases from Lake Powell during water year 2009 shall be made consistent with Section 6.B (Upper Elevation Balancing Tier) of the Interim Guidelines. Consistent with Section 6.B.1 of the Interim Guidelines, the water year release from Lake Powell in 2009 shall be 8.23 maf (10,150 mcm) unless provisions in Section 6.B.3 occur. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2009, Lake Powell elevation to be greater than elevation 3,639.0 feet (1,109.2 meters), Section 6.A (Equalization Tier) of the Interim Guidelines will govern the release of water from Lake Powell for the remainder of water year 2009 (through September 2009). Section 602(a) of the Colorado River Basin Project Act provides for the storage of Colorado River water in Upper Basin reservoirs and the release of water from Lake Powell that the Secretary finds reasonably necessary to assure deliveries to comply with Articles III(c), III(d), and III(e) of the 1922 Colorado River Compact without impairment to the annual consumptive use in the Upper Basin. The Operating Criteria provide that the annual plan of operation shall include a determination of the quantity of water considered necessary to be in Upper Basin storage at the end of the water year after taking into consideration all relevant factors including historic stream flows, the most critical period of record, the 33 ADWR Transport Permit Number entitled Permit to Transport Groundwater Withdrawn from the Yuma Groundwater Basin, March 1, Draft AOP October 21, 2008

33 probabilities of water supply, and estimated future depletions. Water not required to be so stored will be released from Lake Powell: to the extent it can be reasonably applied in the States of the Lower Division to the uses specified in Article III(e) of the 1922 Colorado River Compact, but these releases will not be made when the active storage in Lake Powell is less than the active storage in Lake Mead; to maintain, as nearly as practicable, active storage in Lake Mead equal to the active storage in Lake Powell; and to avoid anticipated spills from Lake Powell. Taking into consideration all relevant factors required by Section 602(a)(3) of the Colorado River Basin Project Act and the Operating Criteria, it is determined that the active storage in Upper Basin reservoirs forecasted for September 30, 2009, under the most probable inflow scenario would exceed the storage required under Section 602(a) of the Colorado River Basin Project Act. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2009, Lake Powell elevation to be greater than elevation 3,639.0 feet (1,109.2 meters), the Equalization Tier, Section 6.A of the Interim Guidelines, will govern the release of water from Lake Powell for the remainder of water year 2009 (through September 2009). Lower Basin Reservoirs Pursuant to Article III of the Operating Criteria and consistent with the Consolidated Decree, water shall be released or pumped from Lake Mead to meet the following requirements: (a) 1944 United States-Mexico Water Treaty obligations; (b) Reasonable beneficial consumptive use requirements of mainstream users in the Lower Division States; (c) Net river losses; (d) Net reservoir losses; (e) Regulatory wastes; and (f) Flood control. The Operating Criteria provide that after the commencement of delivery of mainstream water by means of the CAP, the Secretary will determine the extent to which the reasonable beneficial consumptive use requirements of mainstream users are met in the Lower Division States. Reasonable beneficial consumptive use requirements are met depending on whether a Normal, Surplus, or Shortage Condition has been determined. The Normal Condition is defined as annual pumping and release from Lake Mead sufficient to satisfy maf (9,251 mcm) of consumptive use in accordance with Article III(3)(a) of the Operating Criteria and Article II(B)(1) of the Consolidated Decree. The Surplus Condition is defined as annual pumping and release from Lake Mead sufficient to satisfy in excess of maf (9,251 mcm) of consumptive use in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. An ICS Surplus Condition is Draft AOP October 21, 2008

34 defined as a year in which Lake Mead s elevation is projected to be above elevation 1,075 feet (327.7 meters) on January 1, a Flood Control Surplus has not been determined, and delivery of ICS has been requested. The Secretary may determine an ICS Surplus Condition in lieu of a Normal Condition or in addition to other operating conditions that are based solely on the elevation of Lake Mead. The Shortage Condition is defined as annual pumping and release from Lake Mead insufficient to satisfy maf (9,251 mcm) of consumptive use in accordance with Article III(3)(c) of the Operating Criteria and Article II(B)(3) of the Consolidated Decree. The Interim Guidelines are being utilized in calendar year 2009 and serve to implement the narrative provisions of Article III(3)(a), Article III(3)(b), and Article III(3)(c) of the Operating Criteria and Article II(B)(1), Article II(B)(2), and Article II(B)(3) of the Consolidated Decree for the period through The Interim Guidelines will be used annually by the Secretary to determine the quantity of water available for use within the Lower Division States. Consistent with the Interim Guidelines, the August Month Study was used to forecast the system storage as of January 1, Based on this projected elevation of Lake Mead and consistent with Section 2.B.5 of the Interim Guidelines, the ICS Surplus Condition will govern releases for use in the states of Arizona, Nevada, and California during calendar year 2009 in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. Article II(B)(6) of the Consolidated Decree allows the Secretary to allocate water that is apportioned to one Lower Division State but is for any reason unused in that state to another Lower Division State. This determination is made for one year only, and no rights to recurrent use of the water accrue to the state that receives the allocated water. No unused apportionment for calendar year 2009 is anticipated. If any unused apportionment becomes available after adoption of this AOP, Reclamation, on behalf of the Secretary, shall allocate any such available unused apportionment for calendar year 2009 in accordance with Article II(B)(6) of the Consolidated Decree. Water may be made available for diversion pursuant to 43 CFR Part to contractors within the Lower Division States. The Secretary shall make Intentionally Created Unused Apportionment (ICUA) available to contractors in Arizona, California, or Nevada for the off-stream storage or consumptive use of water pursuant to individual Storage and Interstate Release Agreements (SIRAs) and 43 CFR Part 414. In calendar year 2008, maf (30.84 mcm) of ICUA water stored in Arizona is anticipated to be recovered for use in California 3 by MWD. In calendar year 2008, maf (18.50 mcm) of ICUA water from Nevada is anticipated to be stored in California by MWD. 4 In calendar year 2009, up to maf (43.17 mcm) of ICUA water stored in Arizona is anticipated to be recovered for use in California by MWD. SNWA may propose to make additional unused Nevada basic apportionment available for storage by MWD in The Inadvertent Overrun and Payback Policy (IOPP), which became effective January 1, 2004, will be in effect during calendar year Record of Decision for Implementation Agreement, Inadvertent Overrun and Payback Policy, and Related Draft AOP October 21, 2008

35 The Colorado River Water Delivery Agreement 356 requires payback of California overruns occurring in 2001 and 2002 as noted in Exhibit C of that document. Each district with a payback obligation under Exhibit C may at its own discretion elect to accelerate paybacks. In calendar years 2008 and 2009, paybacks occurring in California result from Exhibit C obligations and IOPP overruns. During calendar year 2008, the California paybacks are projected to total maf (54.27 mcm). In calendar year 2009, California paybacks are projected to total maf acre-feet (4.933 mcm).. During calendar year 2008, the Arizona paybacks are projected to total maf acre-feet (0.740 mcm). In calendar year 2009, Arizona paybacks are projected to total maf acre-feet (0.370 mcm) and.nevada incurred no payback obligation for In calendar year 2009, Nevada paybacks are projected to total maf acre-feet (0.160 mcm). The Interim Guidelines included the adoption of the ICS mechanism that among other things encourages the efficient use and management of Colorado River water in the Lower Basin. If MWD has not recovered all of its Demonstration Program ICS credits during 2008, MWD may request delivery of those credits during In calendar year 2009, MWD may request delivery of up to maf (41.94 mcm) of System Efficiency ICS credits from the Drop 2 Storage Reservoir project. In calendar year 2009, SNWA anticipates creating and taking delivery of maf (37.00 mcm) of Tributary Conservation ICS. Given the limitation of available supply and the low inflow amounts within the Colorado River Basin due to the nine-year drought, the Secretary, through Reclamation, will continue to review Lower Basin operations to assure that all deliveries and diversions of mainstream water are in strict accordance with the Consolidated Decree, applicable statutes, contracts, rules, and agreements. As provided in Section 7.C of the Interim Guidelines, the Secretary may undertake a midyear review to consider revisions of the current AOP. For Lake Mead, the Secretary shall revise the determination in any mid-year review for the current year only to allow for additional deliveries from Lake Mead pursuant to Section 7.C of the Interim Guidelines United States-Mexico Water Treaty Under the most probable, probable minimum, and probable maximum inflow scenarios, water in excess of that required to supply uses in the United States will not be available. Vacant storage space in mainstream reservoirs is substantially greater than that required by flood control regulations. Therefore, a volume of maf (1,850 mcm) of water will be available to be scheduled for delivery to Mexico during calendar year 2009 in accordance with Article 15 of the 1944 United States-Mexico Water Treaty and Minutes 242 and 310 of the IBWC. Federal Actions, Final Environmental Impact Statement, October 10, Colorado River Water Delivery Agreement: Federal Quantification Settlement Agreement for Purposes of Section 5(B) of Interim Surplus Guidelines, October 10, Draft AOP October 21, 2008

36 Calendar year schedules of the monthly deliveries of Colorado River water are formulated by the Mexican Section of the IBWC and presented to the United States Section before the beginning of each calendar year. Pursuant to the 1944 United States-Mexico Water Treaty, the monthly quantity prescribed by those schedules may be increased or decreased by not more than 20 percent of the monthly quantity, upon 30 days notice in advance to the United States Section. Any change in a monthly quantity is offset in another month so that the total delivery for the calendar year is unchanged Draft AOP October 21, 2008

37 DISCLAIMER Nothing in this AOP is intended to interpret the provisions of the Colorado River Compact (45 Stat. 1057); the Upper Colorado River Basin Compact (63 Stat. 31); the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, Treaty Between the United States of America and Mexico (Treaty Series 994, 59 Stat. 1219); the United States/Mexico agreement in Minute No. 242 of August 30, 1973, (Treaty Series 7708; 24 UST 1968); the Consolidated Decree entered by the Supreme Court of the United States in Arizona v. California (547 U.S 150 (2006)); the Boulder Canyon Project Act (45 Stat. 1057); the Boulder Canyon Project Adjustment Act (54 Stat. 774; 43 U.S.C. 618a); the Colorado River Storage Project Act (70 Stat. 105; 43 U.S.C. 620); the Colorado River Basin Project Act (82 Stat. 885; 43 U.S.C. 1501); the Colorado River Basin Salinity Control Act (88 Stat. 266; 43 U.S.C. 1951); the Hoover Power Plant Act of 1984 (98 Stat. 1333); the Colorado River Floodway Protection Act (100 Stat. 1129; 43 U.S.C. 1600); or the Grand Canyon Protection Act of 1992 (Title XVIII of Public Law , 106 Stat. 4669) Draft AOP October 21, 2008

38 ATTACHMENT I Monthly inflow, monthly release, and end-of-month contents for Colorado River reservoirs (October 2008 through December 2009) under the probable maximum, most probable, and probable minimum inflow scenarios, and historic end-of-month contents Draft AOP October 21, 2008

39 Annual Operating Plan for Colorado River Reservoirs 2007 U.S. Department of the Interior Bureau of Reclamation

40 THE SECRETARY OF THE INTERIOR WASHINGTON DEC Honorable Kenny Guinn Governor of Nevada Carson City, Nevada Dear Governor Guinn: Enclosed is the Annual Operating Plan (AOP) for Colorado River System Reservoirs for The AOP was prepared in consultation with representatives of the Governors of the seven Colorado River Basin States, Indian Tribes, Upper Colorado River Commission, appropriate Federal agencies, and others interested in Colorado River operations through meetings of the Colorado River Management Work Group (Work Group). The Work Group held meetings on June 16 and August 16, 2006, and completed consultations at a meeting on September 21, The AOP contains the projected plan of operation of Colorado River reservoirs for 2007 based on the most probable runoff conditions. The plan of operation reflects use of the reservoirs for all purposes consistent with the Criteria for Coordinated Long-Range Operation of Colorado River Reservoirs Pursuant to the Colorado River Basin Project Act of September 30, Enclosure DIRK KEMPTHORNE

41 2 Identical Letters Sent To: Honorable Janet Napolitano Governor of Arizona 1700 West Washington Phoenix, Arizona Honorable Arnold Schwarzenegger Governor of California State Capitol Building Sacramento, California Honorable John Huntsman, Jr. Governor of Utah Utah State Capitol Complex, Suite E220 P.O. Box Salt Lake City, Utah Honorable Bill Richardson Governor of New Mexico State Capitol, Room 400 Santa Fe, New Mexico Honorable David Freudenthal Governor of Wyoming State Capitol 200 West 24 th Street Cheyenne, Wyoming Honorable Bill Owens Governor of Colorado 136 State Capitol Denver, Colorado Colonel Alex Dornstauder District Engineer U.S. Army Corps of Engineers Los Angeles District P.O. Box Los Angeles, California Mr. Steve L. Johnson Administrator Environmental Protection Agency Ariel Rios Building 1200 Pennsylvania Avenue, NW Washington, D.C Mr. Carlos Marin Acting Commissioner, United States Section International Boundary and Water Commission 4171 North Mesa, Suite C-100 El Paso, Texas Mr. Steve L. Johnson Administrator Environmental Protection Agency Ariel Rios Building 1200 Pennsylvania Avenue, NW Washington, D.C Mr. Michael S. Hacskaylo Administrator Western Area Power Administration P.O. Box Lakewood, Colorado

42 cc: Mr. George Caan, Executive Director Colorado River Commission of Nevada 555 East Washington Avenue, Ste Las Vegas, Nevada Mr. Herb Guenther Director Arizona Department of Water Resources 3550 North Central Avenue Phoenix, Arizona Mr. John D' Antonio State Engineer Office of the State Engineer P.O. Box Santa Fe, New Mexico Mr. Gerald R. Zimmerman Executive Director Colorado River Board of California 770 Fairmont Avenue, Suite 100 Glendale, California Mr. Dennis Strong Director Utah Division of Water Resources P.O. Box Salt Lake City, Utah Mr. Alton Goff United States Section International Boundary Water Commission 1940 South 3 rd Avenue, Suite A Yuma, Arizona Mr. Patrick T. Tyrrell State Engineer State of Wyoming Herschler Building, 4 th Floor East Cheyenne, Wyoming Mr. Rod Kuharich Director Colorado Water Conservation Board 1313 Sherman Street, Suite 721 Denver, Colorado Mr. Don Ostler Executive Director Upper Colorado River Commission 355 South 400 East Street Salt Lake City, Utah 84111

43 TABLE OF CONTENTS INTRODUCTION...1 Authority...1 Purpose...1 Summary...2 Upper Basin Delivery...2 Lower Basin Delivery United States-Mexico Water Treaty Delivery HYDROLOGY SUMMARY AND RESERVOIR STATUS WATER SUPPLY ASSUMPTIONS...7 SUMMARY OF RESERVOIR OPERATIONS IN 2006 AND PROJECTED 2007 RESERVOIR OPERATIONS...9 Fontenelle Reservoir...10 Flaming Gorge Reservoir...10 Blue Mesa, Morrow Point, and Crystal Reservoirs (Aspinall Unit)...12 Navajo Reservoir...14 Lake Powell...15 Lake Mead...19 Lakes Mohave and Havasu...21 Bill Williams River...23 Senator Wash and Laguna Reservoirs...23 Imperial Dam...24 Gila River Flows...24 Additional Regulatory Storage...25 Yuma Desalting Plant...25 Lower Basin Demonstration Programs: Intentionally Created Surplus and System Conservation...26 Delivery of Water to Mexico DETERMINATIONS...29 Upper Basin Reservoirs...29 Lower Basin Reservoirs United States Mexico Water Treaty...32 DISCLAIMER...33 ATTACHMENT i 2007 AOP October 28, 2006

44 LIST OF TABLES Table 1. Reservoir Conditions on October 1, 2006 (English Units)...6 Table 2. Reservoir Conditions on October 1, 2006 (Metric Units)...6 Table 3. Projected Unregulated Inflow into Lake Powell for Water Year 2007 (English Units: maf)...8 Table 4. Projected Unregulated Inflow into Lake Powell for Water Year 2007 (Metric Units: mcm)...8 Table 5. Glen Canyon Dam Release Restrictions (Glen Canyon Dam Operating Criteria)...18 Table 6. Scheduled Monthly Releases from Lake Powell in Water Year 2006 Under Most Probable Inflow Conditions...19 ii 2007 AOP October 28, 2006

45 INTRODUCTION Authority This 2007 Annual Operating Plan (AOP) was developed in accordance with Section 602 of the Colorado River Basin Project Act (Public Law ) and the Criteria for Coordinated Long-Range Operation of Colorado River Reservoirs Pursuant to the Colorado River Basin Project Act of September 30, 1968 (Operating Criteria), promulgated by the Secretary of the Interior (Secretary). In accordance with the Colorado River Basin Project Act and the Operating Criteria, the AOP must be developed and administered consistent with applicable Federal laws, the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, Treaty Between the United States of America and Mexico, signed February 3, 1944 (1944 United States-Mexico Water Treaty), interstate compacts, court decrees, Colorado River Interim Surplus Guidelines (Interim Surplus Guidelines) (66 Federal Register 7772, January 25, 2001), Colorado River Water Delivery Agreement (69 Federal Register 12202, March 15, 2004), Interim 602(a) Storage Guideline (69 Federal Register 28945, May 19, 2004), and other documents relating to the use of the waters of the Colorado River, which are commonly and collectively known as The Law of the River. The Operating Criteria and Section 602 of the Colorado River Basin Project Act mandate consultation with representatives of the Governors of the seven Basin States and such other parties as the Secretary may deem appropriate in preparing the annual plan for operation of the Colorado River reservoirs. In addition, the Grand Canyon Protection Act of 1992 (Title XVIII of Public Law ) requires consultation to include the general public and others. Accordingly, the 2007 AOP was prepared by the Bureau of Reclamation in consultation with the seven Basin States Governors representatives; the Upper Colorado River Commission; Native American tribes; appropriate Federal agencies; representatives of the academic and scientific communities, environmental organizations, and the recreation industry; water delivery contractors; contractors for the purchase of Federal power; others interested in Colorado River operations; and the general public, through the Colorado River Management Work Group (CRMWG). Article I(2) of the Operating Criteria allows for revision of this 2007 AOP by June of 2007 to reflect the current hydrologic conditions. Any revision to the AOP may occur only through the AOP consultation process as required by applicable Federal law. Purpose The purposes of the AOP are to determine: (1) the projected operation of the Colorado River reservoirs to satisfy project purposes under varying hydrologic and climatic conditions; (2) the quantity of water considered necessary to be in storage in the Upper Basin reservoirs as of September 30, 2007, pursuant to Section 602(a) of the Colorado River Basin Project Act; (3) water available for delivery pursuant to the 1944 United States- Mexico Water Treaty and Minutes No. 242 and 310 of the International Boundary and Water Commission, United States and Mexico (IBWC); (4) whether the reasonable consumptive use requirements of mainstream users in the Lower Division States will be met AOP October 28, 2006

46 under a Normal, Surplus, or Shortage Condition as outlined in Article III of the Operating Criteria and as implemented by the Interim Surplus Guidelines; and (5) whether water apportioned to, but unused by, one or more Lower Division States exists and can be used to satisfy beneficial consumptive use requests of mainstream users in other Lower Division States as provided in the Consolidated Decree of the Supreme Court of the United States in Arizona v. California, 547 U.S. (2006) (Consolidated Decree). Consistent with the above determinations and in accordance with other applicable provisions of the Law of the River, the AOP was developed with appropriate consideration of the uses of the reservoirs for all purposes, including flood control, river regulation, beneficial consumptive uses, power production, water quality control, recreation, enhancement of fish and wildlife, and other environmental factors (Operating Criteria, Article I(2)). Since the hydrologic conditions of the Colorado River Basin can never be completely known in advance, the AOP addresses the operations resulting from three different hydrologic scenarios: the probable maximum, most probable, and probable minimum reservoir inflow conditions. River operations under the plan are modified during the year as runoff predictions are adjusted to reflect existing snowpack, basin storage, and flow conditions. Summary Upper Basin Delivery. The objective minimum release criterion will most likely control the annual release from Glen Canyon Dam during water year 2007 in accordance with Article II(2) of the Operating Criteria unless spill avoidance and/or the storage equalization criteria in Article II(3) are controlling. To maintain, as nearly as practicable, active storage in Lake Mead equal to the active storage in Lake Powell, releases from Lake Powell greater than the minimum objective of 8.23 million acre-feet (maf), 10,150 million cubic meters (mcm), will be made if (1) storage in Lake Powell on September 30, 2007, is projected to be greater than maf (18,320 mcm) (water surface elevation 3,630 feet [1,106.4 meters]); and (2) active storage in Lake Powell is greater than active storage in Lake Mead, consistent with Article II (3) of the Operating Criteria and Section V of the Interim 602(a) Storage Guideline. Lower Basin Delivery. Under the most probable inflow scenario, downstream deliveries are expected to control the releases from Hoover Dam. Taking into account (1) the existing water storage conditions in the basin, (2) the most probable near-term water supply conditions in the basin, and (3) Sections 2(B)(1) and (7) of the Interim Surplus Guidelines, the Partial Domestic Surplus Condition is the criterion governing the operation of Lake Mead for calendar year 2007 in accordance with Article III(3)(b) of the Operating Criteria, and Article II(B)(2) of the Consolidated Decree. It should be noted, however, that the projected releases in 2007 currently reflect demands under the Normal Condition for the Metropolitan Water District of Southern California (MWD), the Central Arizona Project (CAP), and the Southern Nevada Water Authority (SNWA), per their request. This does not, however, preclude the MWD, CAP, and SNWA from requesting Partial Domestic Surplus water in calendar year AOP October 28, 2006

47 If any unused apportionment is available, the Secretary shall allocate any available unused apportionments for calendar year 2007 in accordance with Article II(B)(6) of the Consolidated Decree and Section 1(B) of the Interim Surplus Guidelines. Water may be made available for diversion pursuant to 43 CFR Part to contractors within the Lower Division States. The Secretary shall make Intentionally Created Unused Apportionment (ICUA) available to contractors in Arizona, California, or Nevada for the off-stream storage or consumptive use of water pursuant to individual Storage and Interstate Release Agreements (SIRA) and 43 CFR Part 414. On October 10, 2003, the Secretary approved the Record of Decision for the Inadvertent Overrun and Payback Policy (IOPP) which became effective January 1, The IOPP will be in effect during calendar year 2007 with calendar year 2005 paybacks to begin in calendar year The Colorado River Water Delivery Agreement requires payback of overruns from 2001 to 2002 as noted in Exhibit C of that document. Each district with a payback obligation under Exhibit C may at its own discretion elect to accelerate paybacks in calendar year It is anticipated that calendar year paybacks for calendar years 2006 and 2007 will total maf (90.11 mcm) and maf (92.58 mcm), respectively. Reclamation implemented two demonstration programs in 2006 in the Lower Basin for Intentionally Created Surplus Water (ICS Water) and System Conservation Water (SC Water). The ICS demonstration program allows entitlement holders to undertake extraordinary conservation activities to reduce their approved annual consumptive use of Colorado River water and store that conserved water in Lake Mead. The ICS demonstration program does not provide for the release or use of ICS Water until appropriate environmental compliance and forbearance agreements have been completed. The SC demonstration program allows entitlement holders to participate in voluntary conservation to conserve a portion of their approved annual consumptive use of Colorado River water in exchange for appropriate compensation provided by Reclamation. The water conserved would be stored and retained in Lake Mead to assist in providing an interim, supplemental source of water to replace the drainage water from the Wellton-Mohawk Irrigation and Drainage District that is bypassed to the Cienega de Santa Clara and the reject stream from operation of the Yuma Desalting Plant United States-Mexico Water Treaty Delivery. A volume of maf (1,852 mcm) of water will be available to be scheduled for delivery to Mexico during calendar year 2007 in accordance with Article 15 of the 1944 United States-Mexico Water Treaty and Minutes No. 242 and 310 of the IBWC. 1 Off-stream Storage of Colorado River Water; Development and Release of Intentionally Created Unused Apportionment in the Lower Division States: Final Rule (43 CFR Part 414) AOP October 28, 2006

48 2006 HYDROLOGY SUMMARY AND RESERVOIR STATUS Below average streamflows were observed in the Colorado River Basin during Unregulated 2 inflow to Lake Powell in water year 2006 was maf (10,820 mcm), or 73 percent of the 30 year average 3 which is maf (14,870 mcm). Unregulated inflow to Flaming Gorge, Blue Mesa, and Navajo Reservoirs was 60, 83, and 62 percent of average, respectively. Snowpack in the Upper Colorado River Basin varied greatly by geographical area throughout the winter of , with the southern regions recording much below average snowpack and the northern regions recording average or above average snowpack. Basinwide snowpack above Lake Powell on April 1, 2006, was 102 percent of average. At that time, the projected April through July inflow to Lake Powell was 97 percent of average. This inflow projection did not hold, however. Below average precipitation was observed in the months of April, May, and June, and inflow projections to Colorado River reservoirs were adjusted downward throughout this period. Observed April through July unregulated inflow to Lake Powell was 5.32 maf (6,560 mcm), or 67 percent of average. The Colorado River Basin experienced five consecutive years of extreme drought during water years 2000 through Unregulated inflow into Lake Powell during this five-year period was only 62, 59, 25, 51, and 49 percent of average, respectively. These years of very low inflow resulted in significant drawdown of Colorado River reservoirs with total system storage decreasing from 92 percent of capacity on October 1, 1999, to 50 percent of capacity on October 1, Hydrologic conditions improved in 2005 with above average inflow to Lake Powell (105 percent of average) and record-breaking tributary flows in the Lower Colorado Basin. Colorado River reservoirs gained 5.10 maf (6,290 mcm) of storage in water year Drier hydrologic conditions returned in Inflow to all major Colorado River reservoirs was below average in Inflow to Lake Powell has been below average in six out of the past seven years. While drought conditions eased in 2005, and the inflow in 2006 was not as low as what occurred in 2000 through 2004, drought conditions in the Colorado River Basin persist. Provisional calculations of natural flow for the Colorado River at Lees Ferry, Arizona, show that the average flow over the last seven water years ( , inclusive) was the lowest sevenyear average in 100 years of record keeping. Although tributary inflows in the Lower Colorado River Basin were exceptionally high during water year 2005, tributary inflows were below average for water year Drought conditions persisted for water year 2006 throughout the State of Arizona. 4 Abnormally dry to severe drought conditions persisted throughout southeastern Arizona, contributing to 75 2 Unregulated inflow adjusts for the effects of operations at upstream reservoirs. It is computed by adding the change in storage and the evaporation losses from upstream reservoirs to the observed inflow. Unregulated inflow is used because it provides an inflow time series that is not biased by upstream reservoir operations. 3 Inflow statistics throughout this document will be compared to the 30-year average, , unless otherwise noted. 4 From the US Drought Monitor website: AOP October 28, 2006

49 percent of average precipitation being recorded in the Gila River Basin. During water year 2006 no tributary inflow from the Gila River reached the mainstem of the Colorado River. By contrast, for water year 2005, tributary inflow from the Gila River Basin that reached the mainstem totaled maf (325.9 mcm). 5 Tributary inflow from the Little Colorado River for water year 2006 also reflected extreme drought conditions in the State of Arizona. Tributary inflow from the Little Colorado for water year 2006 totaled maf (95.05 mcm), or 40 percent of the long-term 6 average. By contrast, tributary inflow for water year 2005 totaled maf (351.8 mcm), or 146 percent of the long-term average of maf (240.7 mcm). Tributary inflow from the Bill Williams River into the mainstem totaled maf (67.89 mcm) for water year 2006, or 50 percent of the long-term average. By contrast, tributary inflow from the Bill Williams River into the mainstem of the Colorado River for water year 2005 totaled maf (640.7 mcm), or 477 percent of the long-term average of maf (134.6 mcm). Tributary inflow from the Virgin River for water year 2006 was below average, totaling maf (200.0 mcm), or 85 percent of the long-term average. By contrast, tributary inflow from the Virgin River for water year 2005 totaled maf (641.9 mcm), or 274 percent of the long-term average of maf (234.5 mcm). Below average inflow to Colorado River reservoirs in 2006 resulted in a net loss in Colorado River total system storage. Reservoir storage in Lake Powell experienced a nominal decline during water year 2006, decreasing by maf (27 mcm). Storage in Lake Mead declined by maf (1,643 mcm) during water year At the beginning of water year 2006, Colorado River total system storage was 59 percent of capacity. As of September 30, 2006, total system storage was 56 percent of capacity, a decrease of approximately 1.41 maf (1,740 mcm). Tables 1 and 2 list the October 1, 2006, reservoir vacant space, live storage, water elevation, percent of capacity, change in storage, and change in water elevation during water year Tributary inflow from the Gila River to the mainstem is very sporadic. These flows occur very seldom and when they do they are typically of high magnitude. 6 The basis for the long-term average is natural flow data from 1906 to Additional information regarding natural flows may be found at Future references to long-term averages will utilize the most recent natural flow database, currently 1906 to AOP October 28, 2006

50 Table 1. Reservoir Conditions on October 1, 2006 (English Units) Reservoir Vacant Space Live Storage Water Elevation Percent of Capacity Change in Storage * Change in Elevation * (maf) (maf) (ft) (%) (maf) (ft) Fontenelle , Flaming Gorge , Blue Mesa , Navajo , Lake Powell , Lake Mead , Lake Mohave Lake Havasu Totals * From October 1, 2005, to September 30, Table 2. Reservoir Conditions on October 1, 2006 (Metric Units) Reservoir Vacant Space Live Storage Water Elevation Percent of Capacity Change in Storage * Change in Elevation * (mcm) (mcm) (m) (%) (mcm) (m) Fontenelle , Flaming Gorge 763 3,861 1, Blue Mesa , Navajo 339 1,751 1, Lake Powell 15,300 14,700 1, Lake Mead 14,790 17, Lake Mohave 278 1, Lake Havasu Totals 31,880 41, ,740 * From October 1, 2005, to September 30, AOP October 28, 2006

51 2007 WATER SUPPLY ASSUMPTIONS For 2007 operations, three reservoir unregulated inflow scenarios were developed and analyzed and are labeled as probable maximum, most probable, and probable minimum. The attached graphs show these inflow scenarios with associated release patterns and endof-month contents for each reservoir. Although there is considerable uncertainty associated with streamflow forecasts and reservoir operating plans made a year in advance, these projections are valuable in analyzing probable impacts on project uses and purposes. The National Weather Service s Colorado Basin River Forecast Center developed the inflow for the probable maximum (10 percent exceedance), most probable (50 percent exceedance), and probable minimum (90 percent exceedance) inflow scenarios in 2007 using the Ensemble Streamflow Prediction (ESP) model. ESP accounts for antecedent streamflows as well as current soil moisture levels with a continuous soil moisture accounting model known as the Sacramento Soil Moisture Accounting Model. The most probable unregulated inflow for Lake Powell in water year 2007 is maf (13,550 mcm), or 91 percent of average. The probable minimum unregulated inflow to Lake Powell in water year 2007 is 4.80 maf (5,920 mcm), or 40 percent of average. The probable maximum unregulated inflow is maf (23,440 mcm), or 158 percent of average. The three inflow scenarios for Lake Powell are shown in Tables 3 and 4. The monthly volumes of inflow resulting from these assumptions were input into Reclamation s monthly reservoir simulation model and used to plan reservoir operations for Starting with October 1, 2006, reservoir storage conditions, the monthly releases for each reservoir were adjusted until release and storage levels best accomplished project purposes. Graphs of the projected 2007 inflows, releases, and storages for each hydrologic scenario are presented in Attachment I AOP October 28, 2006

52 Table 3. Projected Unregulated Inflow into Lake Powell for Water Year 2007 (English Units: maf) Time Period Probable Maximum Most Probable Probable Minimum 10/06 12/ /07 3/ /07 7/ /07 9/ /07 12/ WY CY Table 4. Projected Unregulated Inflow into Lake Powell for Water Year 2007 (Metric Units: mcm) Time Period Probable Maximum Most Probable Probable Minimum 10/06 12/06 3,050 1, /07 3/07 3,130 1, /07 7/07 15,190 8,880 3,840 8/07 9/07 2,080 1, /07 12/07 1,730 1,730 1,730 WY ,440 13,550 5,920 CY ,120 13,650 6, AOP October 28, 2006

53 SUMMARY OF RESERVOIR OPERATIONS IN 2006 AND PROJECTED 2007 RESERVOIR OPERATIONS The regulation of the Colorado River has had effects on downstream aquatic and riparian resources. Controlled releases from dams have modified temperature, sediment load, and flow patterns, resulting in increased productivity of some introduced aquatic resources and the development of economically significant sport fisheries. However, these same releases have detrimental effects on endangered and other native species. Operating strategies designed to protect and enhance downstream aquatic and riparian resources have been established at several locations in the Colorado River Basin. In the Upper Basin, public stakeholder work groups have been established at Fontenelle Dam, Flaming Gorge Dam, the Aspinall Unit, and Navajo Dam. These work groups provide a public forum for dissemination of information regarding ongoing and projected reservoir operations throughout the year and allow stakeholders the opportunity to provide information and feedback with respect to ongoing reservoir operations. At Glen Canyon Dam, the Glen Canyon Dam Adaptive Management Work Group (AMWG), a Federal Advisory Committee Act (FACA) committee, was established in Since its inception, the AMWG has met regularly to analyze and make recommendations to the Secretary regarding research and monitoring programs in the Grand Canyon as well as experimental modifications to dam operations. 7 Modifications to planned operations may be made based on changes in forecast conditions or other relevant factors. Consistent with the Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin (Upper Colorado Recovery Program), 8 the San Juan River Basin Recovery Implementation Program (San Juan Recovery Program), 9 Section 7 consultations under the Endangered Species Act (ESA), and other downstream concerns, modifications to monthly operation plans may be based on other factors in addition to changes in streamflow forecasts. Decisions on spring peak releases and downstream habitat target flows may be made midway through the runoff season. Reclamation will initiate meetings with the U.S. Fish and Wildlife Service (Service), representatives of the Basin States, and with public stakeholder work groups to facilitate the discussions necessary to finalize site-specific operations plans. In 1995, Reclamation and the Service formed a partnership with other Federal, state, and local public agencies and private organizations to develop the Lower Colorado River Multi- Species conservation program (LCR MSCP). This program permits both non-federal and Federal parties to participate in and address ESA compliance requirements under Sections 7 7 Additional information on the AMWG can be found at 8 Additional information on the Upper Colorado Recovery Program can be found at 9 Additional information on the San Juan Recovery Program can be found at AOP October 28, 2006

54 and 10 of the ESA. In April 2005 the Secretary signed the Record of Decision to begin implementation of the MSCP. 10 The following paragraphs discuss the operation of each of the reservoirs with respect to applicable provisions of compacts, the Consolidated Decree, statutes, regulations, contracts, and instream flow needs for maintaining or improving aquatic resources where appropriate. Fontenelle Reservoir Hydrologic conditions in water year 2006 in the Upper Green River Basin were near normal when compared to the historic record for the reservoir. The April through July inflow to Fontenelle Reservoir during water year 2006 was maf (765 mcm), which was 72 percent of average. Fontenelle Reservoir nearly filled in 2006 and bypass releases were necessary in order to accommodate the spring runoff. Inflow peaked at 7,300 cubic feet per second (cfs), 207 cubic meters per second (cms), on May 24, Releases from Fontenelle Reservoir reached a maximum of 4,150 cfs (118 cms) between June 1, 2006, and June 5, These maximum releases were a combination of bypass releases and powerplant releases. The releases through the powerplant during this period were at powerplant capacity, approximately 1,500 cfs (42 cms). The peak elevation of Fontenelle Reservoir during water year 2006 was 6,500.6 feet (1,981.1 meters) above sea level which occurred on July 20, This elevation is 5.4 feet (1.6 meters) below the spillway crest elevation. The most probable April through July inflow to Fontenelle Reservoir during water year 2007 is maf (926 mcm). This volume far exceeds maf (426 mcm), the storage capacity of Fontenelle Reservoir. For this reason, the most probable and probable maximum inflow scenarios require releases during the spring that exceed the capacity of the powerplant to avoid uncontrolled spills from the reservoir. It is very likely that Fontenelle Reservoir will fill during water year In order to minimize high spring releases and to maximize downstream water resources and power production, the reservoir will most likely be drawn down to about elevation 6,468 feet (1,971 meters) by early April 2007, which is five feet (1.5 meters) above minimum power pool, and corresponds to a volume of maf (137 mcm) of live storage. Flaming Gorge Reservoir Inflows to Flaming Gorge Reservoir during water year 2006 were below normal. Unregulated inflow in 2006 was maf (1,284 mcm), which is 60 percent of average. Flaming Gorge Reservoir did not fill during water year On October 1, 2005, the beginning of water year 2006, the reservoir elevation was 6,025.5 feet (1,836.5 meters). The reservoir elevation decreased during water year 2006 and ended water year 2006 (on September 30, 2006) at an elevation of 6,024.2 feet (1,836.1 meters). The water year ending reservoir elevation was 15.8 feet (4.8 meters) below the full pool elevation of 6,040 feet (1,841 meters) which corresponds to an available storage space of maf (763 mcm). 10 Additional information on the MSCP can be found at AOP October 28, 2006

55 On February 16, 2006, the Regional Director of Reclamation s Upper Colorado Region signed a Record of Decision (Flaming Gorge ROD) for the Operation of Flaming Gorge Dam Final Environmental Impact Statement. The Flaming Gorge ROD adopted the Action Alternative as the Federal Action to modify the operation of Flaming Gorge Dam. Under the ROD, releases from Flaming Gorge Dam are patterned so that the peak flows, durations, and base flows and temperatures, described in the Upper Colorado Recovery Program s Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Gorge Dam (Flow and Temperature Recommendations) (September 2000) are achieved to the extent possible, while maintaining and continuing all authorized purposes of Flaming Gorge Dam. Reclamation convened a technical working group, comprised of Service, Western Area Power Administration (Western), and Reclamation personnel, which developed three possible flow scenarios for 2006 spring operations which were consistent with the Flaming Gorge ROD. The flow objective of 18,600 cfs (527 cms) for one day in Reach 2 (the Green River below the confluence with the Yampa River) was one of these three scenarios. In early May 2006, Reclamation decided, based on hydrologic conditions, to attempt to achieve the 18,600 cfs (527 cms) objective for one day in Reach 2. Releases from Flaming Gorge Reservoir were increased to powerplant capacity of 4,550 cfs (129 cms) on May 18, 2006, in anticipation of peak flows on the Yampa River. A bypass release of 2,000 cfs (57 cms) from Flaming Gorge Reservoir was made for 24 hours on May 22-23, 2006, to match high flows of the Yampa River. Green River flows, measured at Jensen, Utah, reached 18,700 cfs (530 cms) on May 24, 2006, as a result of this bypass release. This peak was followed by a second peak which occurred on May 25, 2006, which reached 18,950 cfs (537 cms). The second peak occurred as a result of a precipitation event in the Yampa River Basin. Powerplant capacity releases were made from May 18 to May 30, 2006, to maintain connectivity between the main channel of the Green River and the floodplain depressions where the endangered fish larvae are entrained. Releases were decreased to a base flow level of 1,000 cfs (28 cms) by mid-june. During water year 2007, Flaming Gorge Dam will be operated in accordance with the Flaming Gorge ROD. High spring releases will likely occur in 2007, timed with the Yampa River s spring runoff peak flow, followed by lower summer and autumn base flows. Under the most probable scenario, releases in the winter and early spring of 2007 will be relatively low (approximately 1,200 cfs [34 cms]). The Upper Colorado Recovery Program in coordination with Reclamation, the Service, and Western will conduct studies associated with flood plain inundation. Such studies will include: improving connectivity of flood plain habitats, identifying ways to improve entrainment of larval razorback suckers into floodplain habitats, maintaining the river channel, restoring natural variability of the river system, and analyzing possibilities for meeting the goals of the Flow and Temperature Recommendations at lower peak flow levels where feasible AOP October 28, 2006

56 Blue Mesa, Morrow Point, and Crystal Reservoirs (Aspinall Unit) Near average to below average snowpack conditions prevailed in the Gunnison Basin during water year Most snow measurement sites in the basin reported near average moisture the first week in April, but a rapid decline in snowpack took place throughout April and May. The April through July unregulated runoff into Blue Mesa Reservoir in 2006 was maf (680 mcm), or 77 percent of average, and occurred earlier than normal. Water year 2006 unregulated inflow into Blue Mesa Reservoir was maf (1,020 mcm), or 83 percent of average. Blue Mesa Reservoir filled in 2006 reaching a peak elevation of 7,517.7 feet (2,291.3 meters) on June 17, 2006, only 1.7 feet (0.5 meters) from full pool. Storage in Blue Mesa Reservoir increased during water year 2006 by maf (97 mcm). Storage in Blue Mesa Reservoir on September 30, 2006, was maf (822 mcm), or 80 percent of capacity. Releases from Aspinall Unit reservoirs in 2006 were near normal levels. Releases from the Aspinall Unit provided for a flow of 400 to 500 cfs (11.3 to 14.2 cms) from October 1, 2005, to January 15, 2006, in the Gunnison River through the Black Canyon (below the Gunnison Tunnel). On January 16, 2006, releases were increased to 700 cfs (19.8 cms) in response to slightly above average forecasted inflow. Beginning the last week of March, Crystal releases were increased as the diversions through the Gunnison Tunnel increased. Water year 2006 powerplant bypasses were approximately maf (62 mcm) at Crystal Dam. These bypass releases occurred because the powerplant was shut down for a week in November 2005 and 30 days in February and March of 2006 for maintenance and turbine repair. On August 16, 1995, Memorandum of Agreement (MOA) No R1760 was signed by the Bureau of Reclamation, the Service, and the Colorado Water Conservation Board. The purpose of the MOA was to provide water to the Redlands Fish Ladder, assure at least 300 cfs (8.5 cms) of flow in the 2-mile reach of the Gunnison River between the Redlands Fish Ladder and the confluence of the Gunnison and Colorado Rivers (2-mile reach), and to benefit Colorado River endangered fish. This MOA was extended for an additional five years on June 30, A key provision of the MOA requires that the parties adopt a plan to share water shortages in dry years, when total storage at Blue Mesa Reservoir is projected to drop below 0.4 maf (493 mcm) by the end of the calendar year. However, the MOA was not renewed in Reclamation intends to operate the Aspinall Unit to meet the intent of the MOA if water supplies are available. While deliveries of 100 cfs (2.8 cms) to the Redlands Fish Ladder can be protected under Colorado water law, absent the MOA, the additional releases for the benefit of the 2-mile reach cannot. Releases from the Aspinall Unit combined with runoff from intervening tributaries resulted in water being available for the fish ladder and 2-mile reach of the Gunnison River in In July 2003, a final report titled, Flow Recommendations to Benefit Endangered Fishes in the Colorado and Gunnison Rivers was published by the Upper Colorado Recovery Program. The report compiled and summarized the results of endangered fish research in the Gunnison and Upper Colorado Rivers under the Upper Colorado Recovery Program. The report presents flow recommendations for two different river reaches: one for the lower AOP October 28, 2006

57 Gunnison River between Delta and Grand Junction, Colorado, as measured at Whitewater (Gunnison River near Grand Junction gage); and the other for the Colorado River downstream of the Gunnison River confluence as measured at the Colorado-Utah State line. In January 2004, Reclamation published a Notice of Intent to prepare an environmental impact statement (EIS) on operations to assist with meeting the flow recommendations or a reasonable alternative to them while maintaining authorized project purposes. Public scoping meetings were held in February 2004 and cooperating agency meetings were held in 2005 and A draft EIS is likely to be released in On January 17, 2001, the United States filed an application to quantify the Federal reserved water right decreed to the Black Canyon of the Gunnison National Monument. The water right is for flows in the Gunnison River through the Black Canyon of the Gunnison National Park downstream of the Gunnison Tunnel. On April 2, 2003, the Department of the Interior and the State of Colorado reached agreement regarding water for the Park. Under the 2003 agreement, an amended water right application was filed by the United States for the National Park Service for 300 cfs (8.5 cms) with a 1933 priority date. In a separate action, the Colorado Water Conservation Board filed, under the State of Colorado instream flow program, for additional flows in excess of those required to fulfill the purposes of the Aspinall Unit (with a 2003 priority date) to provide for protection of additional water resources for the Park. The 2003 amended Federal reserved water right application was challenged in United States District Court in Colorado. On September 11, 2006, the District Court set aside the 2003 agreement. Currently, both water right applications filed in state water court remain stayed. In short, the reserved water right claim for the Black Canyon of the Gunnison National Park remains unquantified. For water year 2007, the Aspinall Unit will be operated to conserve storage while meeting downstream delivery requirements, consistent with authorized project purposes. Under normal conditions, the minimum release objectives of the Aspinall Unit are to meet the delivery requirements of the Uncompahgre Valley Project, to meet senior water rights downstream, to the extent possible maintain a year round minimum flow of 300 cfs (8.5 cms) in the Gunnison River through the Black Canyon, and to the extent possible maintain a minimum flow of 300 cfs (8.5 cms) in the 2-mile reach below the Redlands Diversion Dam during the months of July through October. In dry years, the 300 cfs (8.5 cms) flow through the canyon and the 2-mile reach can be reduced. In 2007, under the most probable inflow conditions, flows through the Black Canyon of the Gunnison National Park will be above the 300 cfs (8.5 cms) minimum release objective during the summer months. Consideration shall be given to the gold medal trout fishery in the Black Canyon and recreational interests consistent with project purposes. Releases during 2007 will be planned to minimize large fluctuations in the daily and monthly flows in the Gunnison River below the Gunnison Tunnel diversion. Under the probable minimum inflow scenario, Blue Mesa Reservoir would not fill in Under the most probable and probable maximum inflow scenarios, Blue Mesa Reservoir is expected to fill in AOP October 28, 2006

58 Navajo Reservoir Inflow to Navajo Reservoir in 2006 was less than the 30-year average, marking the sixth year since 1999 that inflows have been below average. The April through July unregulated inflow into Navajo Reservoir in water year 2006 was maf (465 mcm), or 47 percent of average. Water year 2006 unregulated inflow was maf (848 mcm), or 62 percent of average. Unregulated inflow to Navajo Reservoir in water years 2000, 2001, 2002, 2003, 2004, and 2005 was 42, 93, 11, 44, 72, and 136 percent of average, respectively. Storage in Navajo Reservoir was significantly reduced during the 2000 through 2004 period of extreme drought. The above average inflow in 2005 resulted in Navajo Reservoir nearly filling in Carryover storage from 2005 helped maintain storage at Navajo Reservoir at above average levels for most of The reservoir reached a peak water surface elevation of 6,077.9 feet (1,852 meters) on May 26, 2006, 7.1 feet (2.2 meters) from full pool. The water surface elevation at Navajo Reservoir on September 30, 2006, was 6,065.5 feet (1,848.7 meters), with reservoir storage at 84 percent of capacity. The final report titled, Flow Recommendations for the San Juan River (San Juan Flow Recommendations), which outlines flow recommendations for the San Juan River below Navajo Dam, was completed by the San Juan Recovery Program in May 1999 after a sevenyear research period The purpose of the report is to provide flow recommendations for the San Juan River that promote the recovery of the endangered Colorado pikeminnow and razorback sucker, maintain important habitat for these two species as well as the other native species, and provide information for the evaluation of continued water development in the basin. These flow recommendations may be revised in the future to reflect knowledge gained over the last several years of operation. Reclamation completed a National Environmental Policy Act (NEPA) process on the implementation of operations at Navajo Dam that meet the San Juan Flow Recommendations, or a reasonable alternative to them in A Notice of Intent to prepare an EIS was published on October 1, 1999, in the Federal Register. In January 2006, the Service issued a non-jeopardy biological opinion for the operations of Navajo Dam to meet the San Juan Flow Recommendations, or a reasonable alternative. The Navajo Reservoir Operations Final EIS was issued on April 20, The Record of Decision (ROD) for the Navajo Reservoir Operations Final EIS was signed by the Regional Director of Reclamation s Upper Colorado Region on July 31, The San Juan Flow Recommendations called for making the minimum spring peak release from Navajo Reservoir in The spring release pattern implemented in 2006 followed the ramping rates set forth in the San Juan Flow Recommendations. Releases were increased beginning on May 25, A release rate of 5,000 cfs (125 cms) was reached on June 1, 2006, and the release remained at that rate until June 8, Releases were reduced to a base summer release rate of 500 cfs (14 cms) on June 15, At times during the summer months of 2006, higher than normal base flows were released from Navajo Reservoir. Releases from Navajo Reservoir from July through September AOP October 28, 2006

59 averaged 650 cfs (18.4 cms) and were as high as 756 cfs (21.4 cms) in July The higher releases in July 2006 were necessary due to decreasing flows in the San Juan River endangered fish critical habitat area (Farmington, New Mexico, to Lake Powell). The San Juan Flow Recommendations call for an average weekly flow of between 500 cfs (14 cms) and 1,000 cfs (28 cms) in this reach of the river. Once again in 2006, an annual agreement was developed among water users who agreed to limit their water use to the rates/volumes indicated in the agreement. The 2006 Recommendations for Administration and Operation of the San Juan River was similar to the agreements that were developed in 2003, 2004, and Ten major water users (the Jicarilla Apache and Navajo Nations, Hammond Conservancy District, Public Service Company of New Mexico, City of Farmington, Arizona Public Service Company, BHP- Billiton, Bloomfield Irrigation District, Farmers Mutual Ditch, and Jewett Valley Ditch) endorsed the recommendations which included limitations on diversions for 2006, criteria for determining a shortage, and shortage-sharing requirements in the event of a water supply shortfall, including sharing of shortages between the water users and the flow demands for endangered fish habitat. In addition to the ten major water users, the New Mexico Interstate Stream Commission, the Bureau of Indian Affairs, the Service, and the San Juan Recovery Program all provided input to the recommendations. The recommendations were accepted for reservoir operation and river administration purposes by Reclamation and the New Mexico State Engineer. Because of a combination of inflow into Navajo Reservoir in 2006 and above average carryover storage from 2005, no shortages occurred during the 2006 water year. During water year 2007, Navajo Reservoir will be operated in accordance with the Navajo Reservoir Operations ROD. Navajo Reservoir storage levels are expected to be above average in 2007 under the most probable and probable maximum inflow scenarios. Releases from the reservoir will likely be 500 cfs (14 cms) through the fall and winter. Under the probable minimum inflow condition in 2007, the minimum spring peak release as described in the San Juan Flow Recommendations is likely to occur. Lake Powell Reservoir storage in Lake Powell remains relatively low (49 percent of capacity on September 30, 2006) due to effects of continuing drought in the Colorado River Basin. Lake Powell storage was 97 percent of capacity in July Extreme drought conditions were observed in the Colorado River Basin for five consecutive years (water years ) with Lake Powell storage declining during this period. Lake Powell storage on September 30, 2004, was only 38 percent of capacity. Inflow was above average in 2005 and Lake Powell gained 2.77 maf (3,420 mcm) of storage in water year 2005, however. The inflow in 2005 was not sufficient to erase the storage deficit from the preceding five years of extreme drought. Lake Powell began water year 2006 with maf (14,730 mcm) of water in storage (49 percent of capacity). Below average inflow conditions returned in Water year 2006 unregulated inflow to Lake Powell was maf (10,820 mcm), or 73 percent of average. As water year 2006 ended on September 30, 2006, Lake Powell storage was maf (14,700 mcm), or 49 percent of capacity AOP October 28, 2006

60 Due to continued low reservoir storage at Lake Powell, and storage in Lake Powell being less than Lake Mead, releases from Glen Canyon Dam in 2006 were scheduled to maintain the minimum release objective from Lake Powell of 8.23 maf (10,150 mcm) in accordance with Article II(2) of the Operating Criteria. Forecasted inflow to Lake Powell was near average in the early months of 2006 (January through April). However, dry conditions prevailed during the spring months and inflow projections were progressively reduced during the April through July runoff period. Reservoir storage in Lake Powell in 2006 was not sufficient to trigger storage equalization releases from Lake Powell to Lake Mead. The total release from Lake Powell in water year 2006 was 8.23 maf (10,150 mcm). April through July unregulated inflow to Lake Powell in water year 2006 was 5.32 maf (6,560 mcm), or 67 percent of average. Lake Powell reached a seasonal peak elevation of 3,610.9 feet (1,100.5 meters), 89.1 feet (27.2 meters) from full pool, on June 22, On September 30, 2006, the water surface elevation of Lake Powell was 3,601.7 feet ( meters), 98.3 feet (30.0 meters) from full pool. During water year 2007, under the most probable and probable minimum inflow scenario, the objective shall be to maintain a minimum release of water from Lake Powell of 8.23 maf (10,150 mcm) consistent with Article II(2) of the Operating Criteria. Under the probable maximum inflow condition, an annual release of approximately 12.3 maf (15,200 mcm) would be required to equalize storage between Lake Powell and Lake Mead on September 30, Releases to equalize storage between Lakes Powell and Mead will be made in 2007 if storage in Lake Powell is projected to be greater than maf (18,320 mcm) (elevation 3,630 feet [1,106.4 meters]) on September 30, 2007, and active storage in Lake Powell is greater than active storage in Lake Mead. Under the most probable inflow in 2007, the projected water surface elevation at Lake Powell on September 30, 2007, will be 3,619.5 feet (1,103.2 meters) with maf (16,910 mcm) of storage (56 percent of capacity). The Glen Canyon Dam Adaptive Management Program is currently actively evaluating experimental proposals for future operations at Glen Canyon Dam and other related management actions, which may include short-term and/or long-term experimental releases from Glen Canyon Dam. The Science Planning Group, an ad hoc technical committee within the Glen Canyon Dam Adaptive Management Program, analyzed experimental proposals, and through the Glen Canyon Dam Technical Work Group is in the process of providing information and recommendations to the Glen Canyon Dam Adaptive Management Work Group (AMWG). The AMWG, a FACA committee, has not yet made a recommendation to the Secretary on these experimental proposals. Implementation of experimental releases is subject to consistency with the AOP, approval by the Secretary, and completion of appropriate environmental compliance. On September 6, 2006, the AMWG approved a budget and work plan for Included in the work plan is a recommendation to return to operations consistent with the parameters of the Glen Canyon Operating Criteria (the ROD for the Glen Canyon Dam Final Environmental Impact Statement) in water year Pending consideration by the Secretary of this recommendation, experimental flows are not anticipated in While AOP October 28, 2006

61 experimental releases are not anticipated in 2007, any experimental release conducted during water year 2007 would not alter the total volume of water to be released from Lake Powell. In 2007, scheduled maintenance activities at Glen Canyon Dam powerplant will require that one or more of the eight generating units periodically be offline. Coordination between Reclamation offices in Salt Lake City, Utah, and Page, Arizona, will take place in the scheduling of maintenance activities to minimize impacts, including those on potential experimental releases. Because of less than full storage conditions in Lake Powell resulting from drought in the Colorado River Basin, releases for dam safety purposes are highly unlikely in If implemented, releases greater than powerplant capacity would be made consistent with the 1956 Colorado River Storage Project Act, the 1968 Colorado River Basin Project Act, and the 1992 Grand Canyon Protection Act. Reservoir releases in excess of powerplant capacity required for dam safety purposes during high reservoir conditions may be used to accomplish the objectives of the beach/habitat-building flow according to the terms contained in the Glen Canyon Dam Record of Decision (ROD) and as published in the Glen Canyon Dam Operating Criteria (62 Federal Register 9447, Mar. 3, 1997) AOP October 28, 2006

62 Daily and hourly releases in 2007 will be made according to the parameters of the ROD for the Glen Canyon Dam Final Environmental Impact Statement (GCDFEIS) and the Glen Canyon Dam Operating Criteria, as shown in Table 5. Exceptions to these parameters may be made during power system emergencies, during experimental releases, or for purposes of humanitarian search and rescue. Table 5. Glen Canyon Dam Release Restrictions (Glen Canyon Dam Operating Criteria) Parameter (cfs) (cms) Conditions Maximum Flow 11 25, Minimum Flow 5, :00 pm to 7:00 am 8, :00 am to 7:00 pm Ramp Rates Ascending 4, per hour Descending 1, per hour Daily Fluctuations 12 5,000 / 8, / Releases from Lake Powell in water year 2007 will continue to reflect consideration of the uses and purposes identified in the authorizing legislation for Glen Canyon Dam. Powerplant releases will reflect criteria based on the findings, conclusions, and recommendations made in the ROD for the GCDFEIS pursuant to the Grand Canyon Protection Act of 1992 and appropriate NEPA documentation regarding experimental flows. 11 May be exceeded during beach/habitat-building flows, habitat maintenance flows, or when necessary to manage above average hydrologic conditions. 12 Daily fluctuations limit is 5,000 cfs (141.6 cms) for months with release volumes less than maf (740 mcm); 6,000 cfs (169.9 cms) for monthly release volumes of to maf (740 to 987 mcm); and 8,000 cfs (226.6 cms) for monthly release volumes over maf (990 mcm) AOP October 28, 2006

63 The schedule of monthly releases under the most probable inflow scenario for water year 2007 is displayed in Table 6. Table 6. Scheduled Monthly Releases from Lake Powell in Water Year 2007 Under Most Probable Inflow Conditions 13 Month Monthly Release (maf) Monthly Release (mcm) October November December January February March April May June July August September The ten-year total flow of the Colorado River at Lee Ferry 14 for water years 1997 through 2006 is 98.6 maf (122,000 mcm). This total is computed as the sum of the flow of the Colorado River at Lees Ferry, Arizona and the Paria River at Lees Ferry, Arizona, surfacewater discharge stations, which are operated and maintained by the United States Geological Survey. Lake Mead For calendar year 2006, the Partial Domestic Surplus Condition was the criterion governing the operation of Lake Mead in accordance with Article III(3)(b) of the Operating Criteria, Article II(B)(2) of the Consolidated Decree, and Section 2(B)(1) of the Interim Surplus Guidelines. A volume of maf (1,852 mcm) of water was scheduled for delivery to Mexico in accordance with Article 15 of the 1944 United States-Mexico Treaty and Minutes No. 242 and 310 of the International Boundary and Water Commission. Lake Mead began water year 2006 at elevation 1,138.4 feet (347.0 meters), with maf (18,790 mcm) in storage, which is 59 percent of the conservation capacity of maf (31,850 mcm). Lake Mead s elevation increased to elevation 1,141.2 feet (347.8 meters) by the end of February, After February, 2006, Lake Mead steadily declined and ended 13 Modifications to scheduled monthly releases from Lake Powell would be made based on changes in forecast conditions or other relevant factors. 14 A point in the main stream of the Colorado River one mile below the mouth of the Paria River AOP October 28, 2006

64 the water year at an elevation of 1,125.4 feet (343.0 meters), with maf (17,150 mcm) in storage (54 percent of capacity). The total release from Lake Mead through Hoover Dam during water year 2006 was maf (11,600 mcm). The total release from Lake Mead through Hoover Dam during calendar year 2006 is projected to be maf (11,460 mcm). Consumptive use from Lake Mead during calendar year 2006 diverted through the Robert Griffith Water Project is projected to be maf (357.0 mcm). The total inflow into Lake Mead is a combination of water released from Glen Canyon Dam plus inflows from the tributaries in the reach between Glen Canyon and Hoover Dams. In water year 2006, inflow into Lake Mead was maf (11,020 mcm). For water year 2007, total inflow into Lake Mead is anticipated to be maf (11,210 mcm). Under the most probable inflow conditions during water year 2007, Lake Mead will be at its maximum elevation of 1,128.7 feet (344.0 meters), with maf (17,550 mcm) in storage, at the end of January, Lake Mead will likely decline during water year 2007 to reach its minimum elevation of approximately 1,113.2 feet (339.3 meters), with approximately maf (15,690 mcm) in storage, at the end of September, ,16 Based on the August, Month Study, Lake Mead s elevation on January 1, 2007, was projected to be feet (343.7 meters). Therefore, in accordance with Section 7 of the Interim Surplus Guidelines, the Partial Domestic Surplus Condition will govern the releases from Lake Mead in calendar year It should be noted, however, that the projected releases in 2007 currently reflect demands under the Normal Condition for the MWD, CAP, and SNWA, per their request. This does not, however, preclude the MWD, CAP, and SNWA from requesting Partial Domestic Surplus water in calendar year Releases from Lake Mead through Hoover Dam for water year and calendar year 2007 are anticipated to be approximately the same as 2006 releases. Some variability between the 2006 and 2007 releases may result from the two demonstration programs to create ICS Water in Lake Mead and to achieve System Conservation (SC). The Interim Surplus Guidelines ROD included ESA conservation measures. One such conservation measure specified in Article X(4)(1) includes provisions for spawning razorback suckers in Lake Mead. Reclamation continues to provide funding and support for the ongoing Lake Mead Razorback Sucker study. The focus of the study has been on locating populations of razorbacks in Lake Mead, documenting use and availability of spawning areas at various water elevations, continuing aging studies, and confirming recruitment events. Based on the anticipated operation of Lake Powell for water year 2007, 15 In calendar year 2006, it is assumed that 50,000 acre-feet and 1,000 acre-feet of ICS Water would be conserved by the MWD and the Imperial Irrigation District (IID), respectively. In calendar year 2007, it was assumed that 50,000 acre-feet and 1,000 acre-feet of ICS Water would be conserved by the MWD and the IID, respectively. 16 In calendar year 2006, it was assumed that 3,000 acre-feet of SC Water would be conserved. In calendar year 2007, it was assumed that 7,000 acre-feet of SC Water would be conserved AOP October 28, 2006

65 no changes in operations to provide rising elevations in Lake Mead are expected in the spring of In a letter to the Governors of the seven Colorado River Basin States (May 2, 2005), the Secretary directed Reclamation to develop Colorado River Lower Basin shortage guidelines and coordinated reservoir management strategies for Lake Powell and Lake Mead under low reservoir conditions. A notice to solicit comments and hold public meetings on the development of the guidelines and strategies was issued on June 15, 2005 (70 Federal Register 34,794). A Notice of Intent was issued on September 30, 2005 (70 Federal Register 57,322) to prepare an EIS and hold public scoping meetings on the proposed action. Key milestones in the EIS process include: (1) the Scoping Summary Report, published March 31, 2006 (71 Federal Register 16,341); (2) draft alternatives published June 30, 2006; (3) a Draft EIS targeted in February, 2007; (4) a Final EIS targeted in September 2007; and (5) a Record of Decision targeted in December Lakes Mohave and Havasu At the beginning of water year 2006, Lake Mohave was at an elevation of feet (194.6 meters), with an active storage of maf (1,942 mcm). The water level of Lake Mohave was regulated between elevation feet (193.3 meters) and feet (196.1 meters) throughout the water year, ending at an elevation of feet (194.7 meters) with maf (1,955 mcm) in storage. The total release from Lake Mohave through Davis Dam for water year 2006 was maf (11,300 mcm) for downstream water use requirements. The calendar year 2006 total release is projected to be maf (11,200 mcm). For water year and calendar year 2007, Davis Dam is expected to release approximately the same amount of water as in The water level in Lake Mohave will be regulated between an elevation of approximately 630 feet (192 meters) and 645 feet (197 meters). Lake Havasu started water year 2006 at an elevation of feet (136.1 meters) with maf (683.9 mcm) in storage. The water level of Lake Havasu was regulated between elevation feet (135.9 meters) and feet (136.8 meters). During water year 2006, maf (8,258 mcm) were released from Parker Dam. The calendar year 2006 total release is projected to be maf (8,352 mcm). Diversions from Lake Havasu during calendar year 2006 by the CAP and the MWD are projected to be maf (1,982 mcm) and maf (765.3 mcm), respectively. For water year 2007, Parker Dam is expected to release approximately the same amount of water as in Diversions from Lake Havasu in calendar year 2007 by the CAP and the MWD are expected to be maf (1,976 mcm) and maf (720.9 mcm), respectively. 17 Additional information on the EIS for the Development of Lower Colorado River Basin Shortage Guidelines & Coordinated Management Strategies for Lakes Powell and Mead Under Low Reservoir Conditions may be found at AOP October 28, 2006

66 Lakes Mohave and Havasu are scheduled to be drawn down in the late summer and fall months to provide storage space for local storm runoff and will be filled in the winter to meet higher summer water needs. This drawdown will also correspond with normal maintenance at both Davis and Parker powerplants which is scheduled for September through February. At Davis Dam, a major overhaul of Unit No. 3 is scheduled for October 2, 2006, through February 16, This overhaul will include removal and maintenance of the fixed wheel gate and hydraulic cylinder, as well as testing the generator windings and station service transformer. Rehabilitation of Units 1, 2, 4, and 5 has yet to be decided by both Reclamation and funding board customers. No major overhauls at Parker Dam have been scheduled for water year During 2007, Lake Mohave will continue to be operated under the constraints as described in the Interim Surplus Guidelines Biological and Conference Opinion on Lower Colorado River Operations and Maintenance, as extended through the LCR MSCP Biological and Conference Opinion. Reclamation, as provided in the LCR MSCP ROD, will continue these existing operations in Lake Mohave that benefit native fish and will explore additional ways to provide benefits to native fish. The normal filling and drawdown pattern of Lake Mohave coincides well with the fishery spawning period. Since lake elevations for Lake Mohave and Lake Havasu will be typical of previous years, normal conditions are expected for boating and other recreational uses. Reclamation is the lead agency in the Native Fish Work Group, a multi-agency group of scientists attempting to augment the ageing stock of the endangered razorback sucker in Lake Mohave. Larval razorback suckers are captured by hand in and around spawning areas in late winter and early spring for rearing at Willow Beach National Fish Hatchery below Hoover Dam. The following year, 1-year old razorback suckers are placed into predatorfree, lake-side backwaters for rearing through the spring and summer. When Lake Mohave is normally drawn down during August through October, these fish are harvested from these rearing areas and then released into Lake Mohave. The razorback suckers grow very quickly, usually exceeding 10 inches in length by September. In 2005, 12,203 razorback suckers (325 mm minimum size) were repatriated into Lake Mohave from all sources, a 29% decrease compared to In 2006, 63,749 wild razorback suckers were captured from natural spawning congregations on Lake Mohave and delivered to Willow Beach National Fish Hatchery, a 5% increase compared to AOP October 28, 2006

67 Bill Williams River Although tributary inflows from the Bill Williams River were exceptionally high during water year 2005, tributary inflows were below average for water year Moderate to severe drought conditions persisted for water year 2006 throughout western Arizona, including the Bill Williams River watershed. Tributary inflow from the Bill Williams River into the mainstem of the Colorado River totaled maf (67.89 mcm) for water year 2006, approximately 50 percent of the long-term average of maf (23.45 mcm). Above average flood control releases from the U.S. Army Corps of Engineer s (USACE) Alamo Dam during water year 2005 enhanced riparian habitat along the Bill Williams River corridor. Releases in water year 2006 from USACE s Alamo Dam were coordinated with the Service and the Bill Williams Steering Committee to maintain riparian habitat established in water year Although standing operating procedures target an Alamo Lake elevation of approximately 1,125 feet (342.9 meters), the elevation was maintained at approximately 1,130 feet (344.4 meters) after October 1, A storage volume of maf (23.45 mcm), equivalent to the storage between approximately elevations 1,130 feet (344.4 meters) and 1,125 feet (342.9 meters), was released beginning March 13, The purpose of the release was to lower the Alamo Lake elevation to approximately 1,125 feet (342.9 meters), and maintain downstream riparian habitat. The March 13, 2006, release from Alamo Dam increased from approximately 40 cfs (1 cms) to approximately 2,000 cfs (60 cms) for a two day period, tapering to approximately 40 cfs (1 cms) over the following two weeks. Data collection associated with Alamo Dam releases supports ongoing studies conducted by the Bill Williams Steering Committee. The Bill Williams Steering Committee is chaired by the Service and is comprised of other stakeholders, including, but not limited to, Reclamation, the USACE, the Bureau of Land Management, and other governmental and non-governmental organizations. Senator Wash and Laguna Reservoirs Operations at Senator Wash Reservoir allow regulation of water deliveries to United States water users upstream and downstream of Imperial Dam and Mexican water users downstream of Imperial Dam. The reservoir is utilized as an off-stream storage facility to meet downstream water demands and to conserve water for future uses in the United States and the scheduled uses of Mexico in accordance with Treaty obligations. Senator Wash Reservoir is the only major storage facility below Parker Dam (approximately 142 river miles downstream) and has a storage capacity of maf (17.04 mcm) at full pool elevation of feet (76.5 meters). Operational objectives are to store excess flows from the river caused by water user cutbacks and side wash inflows due to rain. Stored waters are utilized to meet the United States and Mexico s demands. Since 1992, elevation restrictions have been placed on Senator Wash due to potential piping and liquefaction of foundation and embankment materials at West Squaw Lake Dike and Senator Wash Dam. Currently, Senator Wash is restricted to an elevation of feet (73.2 meters) with maf (11.28 mcm) of storage, a loss of about maf (5.802 mcm) of storage from its original capacity. Senator Wash elevation must not exceed elevation AOP October 28, 2006

68 feet (73.2 meters) for more than 10 consecutive days. This reservoir restriction is expected to continue in Laguna Reservoir is a regulating storage facility located approximately five river miles downstream of Imperial Dam. Operational objectives are similar to those for Senator Wash Reservoir and are primarily used to capture sluicing flows from Imperial Dam. The storage capability of Laguna Reservoir has diminished from about 1500 acre-feet (1.852 mcm) to approximately 400 acre-feet (0.494 mcm) due to sediment accumulation and vegetation growth. Sediment accumulation in the reservoir has occurred primarily due to flood releases that occurred in 1983 and 1984, and flood control or space building releases that occurred between 1985 and 1988 and from 1997 through Action to restore the lost capacity at the Laguna Reservoir is ongoing. It is anticipated that dredging to restore its capacity will begin in early 2007, and be completed within a 3 year period, subject to the availability of funds and the completion of the environmental compliance process. Imperial Dam Imperial Dam is the last diversion dam on the Colorado River for United States water users. From the head works at Imperial Dam, the diversions of flows for the United States and Mexico s water users occur into the All-American Canal on the California side, and into the Gila Gravity Main Canal on the Arizona side of the dam. These diversions supply all the irrigation districts in the Yuma area, in Wellton-Mohawk, in the Imperial and Coachella Valleys, and through Siphon Drop and Pilot Knob to the Northerly International Boundary (NIB) to the Mexicali Valley in Mexico. The diversions also supply much of the domestic and industrial water needs in the Yuma area. Flows arriving at Imperial Dam for calendar year 2006 are expected to be maf (7,061 mcm). The flows arriving at Imperial Dam for calendar year 2007 are anticipated to be approximately the same as calendar year Dredging of Imperial Reservoir was completed on June 1, 2006, resulting in the removal of 1.2 million cubic yards (0.9 mcm) of material from the reservoir. This dredging is done periodically to remove sediment that might impede diversions to water users from Imperial Dam. This dredging also temporarily increases the storage behind Imperial Dam by about 500 acre-feet. Gila River Flows Drought conditions persisted for water year 2006 throughout the State of Arizona. Abnormally dry to severe drought conditions persisted throughout southeastern Arizona, contributing to 75 percent of average precipitation being recorded in the Gila River Basin. During water year 2006 no tributary inflow from the Gila River reached the mainstem of the Colorado River. By contrast, for water year 2005, tributary inflow from the Gila River Basin that reached the mainstem totaled maf (325.9 mcm) AOP October 28, 2006

69 Additional Regulatory Storage In 2004, Reclamation completed a study that evaluated the needs and developed options for additional water storage facilities on the mainstem of the Colorado River below Parker Dam. The study, developed in cooperation with the IID, Coachella Valley Water District (CVWD), San Diego County Water Authority (SDCWA), and the MWD, recommended that additional storage be constructed at a site north of Drop 2 along the All-American Canal. The proposed Drop 2 reservoir is in the engineering design and environmental compliance and permitting stage. The purpose of the planned maf (9.875 mcm) reservoir is the same as Senator Wash and it will be operated similar to Senator Wash to capture extra water in the system, especially during storm events. The reservoir will make up for the loss of water storage at Senator Wash because of the operational restrictions and allow for additional regulatory storage. Additional storage will allow for more efficient management of water below Parker Dam. Construction of the first phase of the Drop 2 reservoir is scheduled to start in calendar year 2007 and be completed in late calendar year 2009, with a capacity of maf (4.938 mcm) of storage. This schedule is subject to completion of appropriate compliance and the availability of funds and obtaining the necessary permits to perform the work. Yuma Desalting Plant The Yuma Desalting Plant (YDP) was not operated in calendar year 2006 and is being maintained in a ready reserve status. In calendar year 2006 the amount of water discharged through the Main Outlet Drain (bypass flows) is anticipated to be maf (135.8 mcm) at an approximate concentration of total dissolved solids of 2,430 parts per million (ppm). Water users in the Colorado River Basin have raised concerns over the continued bypass of Wellton-Mohawk agricultural return flow around Morelos Dam to the Cienega de Santa Clara, a wetland of approximately 40,000 acres (16,200 hectares) that is within a Biosphere Reserve in Mexico. These flows do not count as part of Mexico s maf (1,852 mcm) allotment under the Treaty of On October 26, 2005, Reclamation submitted to Congress a report that describes activities required to operate the YDP, provides an estimate of how long those activities would take, and presents a current estimate of their anticipated cost. In addition, this report explores interim and/or supplemental opportunities for replacement of water that is bypassed into Mexico, including options that do not potentially have an adverse impact on the Cienega de Santa Clara. Reclamation initiated a public process on September 22, 2005 to investigate options to replace or recover the bypass flows. In January 2005, Commissioner John Keys announced the United States commitment to demonstrate operation of the YDP at a bi-national meeting of the IBWC. Preparations for the demonstration are well underway and this operation is scheduled to begin in March For the demonstration, the YDP will operate at about 10 percent of full capacity for a AOP October 28, 2006

70 period of 90 days. It is anticipated that about maf (3.703 mcm) will be stored in Lake Mead as a result of recovered bypass flows in calendar year Lower Basin Demonstration Programs: Intentionally Created Surplus and System Conservation Water Reclamation implemented two demonstration programs in 2006 in the Lower Basin for Intentionally Created Surplus Water (ICS Water) and System Conservation Water (SC Water). The ICS demonstration program allows entitlement holders to undertake extraordinary conservation activities to reduce their approved annual consumptive use of Colorado River water and store that conserved water in Lake Mead. The ICS demonstration program does not provide for the release or use of ICS Water until appropriate environmental compliance and forbearance agreements have been completed. The SC demonstration program allows entitlement holders to participate in voluntary conservation to conserve a portion of their approved annual consumptive use of Colorado River water in exchange for appropriate compensation provided by Reclamation. The water conserved would be stored and retained in Lake Mead to assist in providing an interim, supplemental source of water to replace the drainage water from the Wellton-Mohawk Irrigation and Drainage District that is bypassed to the Cienega de Santa Clara and the reject stream from operation of the Yuma Desalting Plant. Intentionally Created Surplus Water (ICS Water) Agreements Reclamation has entered into an agreement with the MWD for the creation of Intentionally Created Surplus Water (ICS Water) in 2006 and Through this program, the MWD may undertake extraordinary conservation measures to create up to maf (61.72 mcm) in calendar year The MWD may, either separately or in conjunction with other California agencies with rights to use Colorado River water, create up to maf (246.9 mcm) in calendar year Currently, the MWD anticipates creating maf (61.72 mcm) per year in calendar years 2006 and Reclamation has also entered into an agreement with the IID for the creation of ICS Water in 2006 and Through this program, the IID will undertake extraordinary conservation measures to create up to maf (6.172 mcm) in calendar year 2006 and up to maf (30.86 mcm) in calendar year Currently, the IID anticipates creating maf (1.234 mcm) per year in calendar years 2006 and Implement a Demonstration Program to Create Intentionally Created Surplus Water, between Reclamation and the MWD, dated May 18, Implement a Demonstration Program to Create Intentionally Created Surplus Water, between Reclamation and the IID, dated June 26, AOP October 28, 2006

71 System Conservation Water (SC Water) Agreements Reclamation has entered into an agreement with the MWD for the creation of SC Water in 2006 and Through this program, the MWD will undertake extraordinary conservation measures to create maf (3.703 mcm) of SC Water in calendar year 2006 and maf (8.641 mcm) of SC Water in calendar year This water will be stored and retained in Lake Mead. Delivery of Water to Mexico Total delivery to Mexico for calendar year 2006 is projected to be approximately maf (1,889 mcm), an over-delivery of approximately maf (37.03 mcm). Of the total delivery, approximately maf (172.8 mcm) is projected to be delivered at the Southerly International Boundary (SIB) and maf (1,716 mcm) is projected to be delivered at the NIB. The over-deliveries in 2006 resulted from a combination of rejected water from water users after rain storms, side-wash inflow into the Colorado River, and spills from irrigation facilities below Imperial Dam to the river. As part of Mexico s delivery schedule, it is anticipated that acre-feet (0.126 mcm) will be diverted from Lake Havasu to Tijuana, Baja California at the request of the Mexican section of the IBWC in calendar year In 2007, it is anticipated that maf (172.8 mcm) will be delivered to Mexico at the SIB. In accordance with Minute No. 310 and the Emergency Delivery Agreement 21 up to maf per month (1.481 mcm) may be delivered for Tijuana. The remainder of Mexico s available water will be delivered at NIB. To further improve control of the deliveries of water from Parker Dam, Senator Wash Reservoir and the reservoirs behind Imperial Dam and Laguna Dam will continue to be operated at lower elevations during periods of potential rain storms to capture flows in excess of water demand at Imperial Dam. Improvements to the river routing software used to schedule the releases from Parker Dam have also reduced the uncertainty in estimating the flows arriving at Imperial Dam, further helping to reduce non-storable flows arriving at Imperial Dam. As mentioned previously, the proposed Drop 2 Reservoir would improve control of water deliveries below Parker Dam once construction is complete. Drainage flows to the Colorado River from the Yuma Mesa Conduit and South Gila Conduit are projected to be maf (53.08 mcm) and maf (82.71 mcm), respectively, for calendar year As stated in Minute 242, the maximum allowable salinity differential is 145 ppm by the United States measurement or count and 151 ppm by the Mexican count. The salinity differential for calendar year 2006 is projected to be 143 ppm by the United States count. 20 Implement a Demonstration Program for System Conservation of Colorado River Water, between Reclamation and the MWD, dated August 15, The Agreement for Temporary Emergency Delivery of a Portion of the Mexican Treaty Waters of the Colorado River to the International Boundary in the Vicinity of Tijuana, Baja California, Mexico, and for Operation of the Facilities in the United States, applicable through calendar year AOP October 28, 2006

72 Mexico has identified four critical months, October through January, regarding improving the quality of water delivered at the SIB. As a matter of comity, the United States has agreed to reduce the salinity of water delivered at SIB. To accomplish the reduction in salinity, the United States constructed a diversion channel to bypass up to maf (9.875 mcm) of Yuma Valley drainage water during the four critical months identified by Mexico. This water will be replaced by better quality water from the Minute 242 well field to reduce the salinity at SIB. Currently, the facilities required for real time monitoring and control of the flow and salinity of water delivered to SIB will be fully operational in Fiscal Year In 2006 and 2007, about maf (9.875 mcm) of water is expected to be spilled to the diversion channel each year for salinity control AOP October 28, 2006

73 2007 DETERMINATIONS The AOP provides guidance regarding reservoir storage and release conditions during the upcoming year, based upon congressionally mandated and authorized storage, release, and delivery criteria and determinations. After meeting these requirements, specific reservoir releases may be modified within these requirements as forecasted inflows change in response to climatic variability and to provide additional benefits coincident to the projects multiple purposes. Upper Basin Reservoirs The objective minimum release criterion will most likely control the annual release from Glen Canyon Dam during water year 2007 in accordance with Article II(2) of the Operating Criteria unless spill avoidance and/or the storage equalization criteria in Article II(3) are controlling. Under the most probable and minimum probable inflow scenario, the objective shall be to maintain a minimum release of water from Lake Powell of 8.23 maf (10,150 mcm) in water year Under the maximum probable inflow scenario, storage equalization would control the release of water from Lake Powell in water year Pursuant to Section 602(b) of the Colorado River Basin Project Act and Section 1804 (c)(3) of the Grand Canyon Protection Act, the Secretary is required to develop this AOP in consultation with the Upper Colorado River Commission, representatives from the three Lower Division States, and with the general public. Section 602(a) of the Colorado River Basin Project Act provides for the storage of Colorado River water in Upper Basin reservoirs and the release of water from Lake Powell that the Secretary finds reasonably necessary to assure deliveries to comply with Articles III(c), III(d), and III(e) of the 1922 Colorado River Compact without impairment to the annual consumptive use in the Upper Basin. The Operating Criteria provide that the annual plan of operation shall include a determination of the quantity of water considered necessary to be in Upper Basin storage at the end of the water year after taking into consideration all relevant factors including historic stream flows, the most critical period of record, the probabilities of water supply, and estimated future depletions. Water not required to be so stored will be released from Lake Powell: to the extent it can be reasonably applied in the States of the Lower Division to the uses specified in Article III(e) of the 1922 Colorado River Compact, but these releases will not be made when the active storage in Lake Powell is less than the active storage in Lake Mead; to maintain, as nearly as practicable, active storage in Lake Mead equal to the active storage in Lake Powell; and to avoid anticipated spills from Lake Powell. Taking into consideration all relevant factors required by Section 602(a)(3) of the Colorado River Basin Project Act, the Operating Criteria, and the Interim 602(a) Storage Guideline, it AOP October 28, 2006

74 is determined that the active storage in Upper Basin reservoirs forecast for September 30, 2007, under the most probable inflow scenario would not exceed the storage required under Section 602(a) of the Colorado River Basin Project Act. Consistent with Section V of the Interim 602(a) Storage Guideline, releases from Lake Powell greater than the minimum objective of 8.23 maf (10,150 mcm), to maintain, as nearly as practicable, active storage in Lake Mead equal to the active storage in Lake Powell, will be made if storage in Lake Powell, on September 30, 2007, is projected to be greater then maf (18,320 mcm) (water surface elevation 3,630 feet [1,106.4 meters]) and active storage in Lake Powell is greater than active storage in Lake Mead. Lower Basin Reservoirs Pursuant to Article III of the Operating Criteria and consistent with the Consolidated Decree, water shall be released or pumped from Lake Mead to meet the following requirements: (a) 1944 United States-Mexico Water Treaty obligations, (b) Reasonable beneficial consumptive use requirements of mainstream users in the Lower Division States, (c) Net river losses, (d) Net reservoir losses, (e) Regulatory wastes, (f) Flood control. The Operating Criteria provide that after the commencement of delivery of mainstream water by means of the CAP, the Secretary will determine the extent to which the reasonable beneficial consumptive use requirements of mainstream users are met in the Lower Division States. Reasonable beneficial consumptive use requirements are met depending on whether a Normal, Surplus, or Shortage Condition has been determined. The Normal Condition is defined as annual pumping and release from Lake Mead sufficient to satisfy maf (9,258 mcm) of consumptive use in accordance with Article III(3)(a) of the Operating Criteria and Article II(B)(1) of the Consolidated Decree. The Surplus Condition is defined as annual pumping and release from Lake Mead sufficient to satisfy in excess of maf (9,258 mcm) consumptive use in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. The Interim Surplus Guidelines, which became effective February 26, 2001, and were first utilized in calendar year 2002, serve to implement the narrative provisions of Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree for the period through These specific interim surplus guidelines will be used annually by the Secretary to determine the quantity of water available for use within the Lower Division States. Consistent with Section 7 of the Interim Surplus Guidelines, the August, Month Study was used to forecast the system storage as of January 1, Based on this projected elevation, the Partial Domestic Surplus Condition will govern releases for use in the states AOP October 28, 2006

75 of Arizona, Nevada, and California during calendar year 2007 in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. It should be noted, however, that the projected releases in 2007 currently reflect demands under the Normal Condition for the MWD, the CAP, and the SNWA, per their request. This does not, however, preclude the MWD, CAP and SNWA from requesting Partial Domestic Surplus water in calendar year Article II(B)(6) of the Consolidated Decree allows the Secretary to allocate water that is apportioned to one Lower Division State but is for any reason unused in that state to another Lower Division State. This determination is made for one year only, and no rights to recurrent use of the water accrue to the state that receives the allocated water. If any unused apportionment is available the Secretary shall allocate any available unused apportionment for calendar year 2007 in accordance with Article II(B)(6) of the Consolidated Decree, and Section 1(B) of the Interim Surplus Guidelines. Water may be made available for diversion pursuant to 43 CFR Part 414 to contractors within the Lower Division States. The Secretary shall make Intentionally Created Unused Apportionment (ICUA) available to contractors in Arizona, California, or Nevada for the off-stream storage or consumptive use of water pursuant to individual SIRA agreements and 43 CFR Part 414. On October 10, 2003, the Secretary approved the ROD for the Inadvertent Overrun and Payback Policy (IOPP) which became effective January 1, The IOPP is in effect during calendar year 2007 with calendar year 2005 paybacks to begin in calendar year The Colorado River Water Delivery Agreement also requires payback of 2001 and 2002 overruns as noted in Exhibit C of that document. Each district with a payback obligation under Exhibit C may, at its own discretion, elect to accelerate paybacks in calendar year It is anticipated that calendar year paybacks for calendar years 2006 and 2007 will total maf (90.11 mcm), and maf (92.58 mcm), respectively. Given the limitation of available supply and the low inflow amounts within the Colorado River Basin, the Secretary, through Reclamation, will continue to review Lower Basin operations to assure that all deliveries and diversions of mainstream water are in strict accordance with the Consolidated Decree, applicable statutes, contracts, rules, and agreements. As provided in Section 3 of the Interim Surplus Guidelines, the Secretary shall undertake a mid-year review pursuant to Article I(2) of the Operating Criteria, allowing for the revision of the current AOP, as appropriate, based on actual runoff conditions which are greater than projected or demands which are lower than projected. The Secretary shall revise the determination for the current year only to allow for additional deliveries. Any revision to the AOP may occur only through the AOP consultation process as required by applicable Federal law AOP October 28, 2006

76 1944 United States-Mexico Water Treaty Under the most probable, probable minimum, and probable maximum inflow scenarios, water in excess of that required to supply uses in the United States will not be available. Vacant storage space in main stem reservoirs is substantially greater than that required by flood control regulations. Therefore, a volume of maf (1,852 mcm) of water will be available to be scheduled for delivery to Mexico during calendar year 2007 in accordance with Article 15 of the 1944 United States-Mexico Water Treaty and Minutes 242 and 310 of the IBWC. Calendar year schedules of the monthly deliveries of Colorado River water are formulated by the Mexican Section of the IBWC and presented to the United States Section before the beginning of each calendar year. The monthly quantity prescribed by those schedules may be increased or decreased by not more than 20 percent of the monthly quantity, upon 30 days notice in advance to the United States Section. Any change in a monthly quantity is offset in another month so that the total delivery for the calendar year is unchanged AOP October 28, 2006

77 DISCLAIMER Nothing in this AOP is intended to interpret the provisions of the Colorado River Compact (45 Stat. 1057); the Upper Colorado River Basin Compact (63 Stat. 31); the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, Treaty Between the United States of America and Mexico (Treaty Series 994, 59 Stat. 1219); the United States/Mexico agreement in Minute No. 242 of August 30, 1973, (Treaty Series 7708; 24 UST 1968); the Consolidated Decree entered by the Supreme Court of the United States in Arizona v. California (547 U.S. (2006) ); the Boulder Canyon Project Act (45 Stat. 1057); the Boulder Canyon Project Adjustment Act (54 Stat. 774; 43 U.S.C. 618a); the Colorado River Storage Project Act (70 Stat. 105; 43 U.S.C. 620); the Colorado River Basin Project Act (82 Stat. 885; 43 U.S.C. 1501); the Colorado River Basin Salinity Control Act (88 Stat. 266; 43 U.S.C. 1951); the Hoover Power Plant Act of 1984 (98 Stat. 1333); the Colorado River Floodway Protection Act (100 Stat. 1129; 43 U.S.C. 1600); or the Grand Canyon Protection Act of 1992 (Title XVIII of Public Law , 106 Stat. 4669) AOP October 28, 2006

78 ATTACHMENT 1 Monthly inflow, monthly release, and end of month contents for Colorado River reservoirs (October 2005 through December 2007) under the probable maximum, most probable, and probable minimum inflow scenarios, and historic end of month contents AOP October 28, 2006

79 600 Fontenelle Monthly Inflow Probable Minimum Most Probable Probable Maximum 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

80 450 Fontenelle Monthly Releases Probable Minimum Most Probable Probable Maximum 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

81 350 Fontenelle Monthly Storage AF Probable Minimum Most Probable Probable Maximum 0 Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

82 800 Flaming Gorge Monthly Inflow Probable Minimum Most Probable Probable Maximum 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

83 350 Flaming Gorge Monthly Releases Probable Minimum Most Probable Probable Maximum 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

84 3800 Flaming Gorge Monthly Storage Probable Minimum Most Probable Probable Maximum 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

85 500 Blue Mesa Monthly Inflow 1000 AF Probable Minimum Most Probable Probable Maximum 0 Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

86 300 Crystal Monthly Releases 1000 AF Probable Minimum Most Probable Probable Maximum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

87 900 Blue Mesa Monthly Storage AF Probable Minimum Most Probable Probable Maximum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

88 Navajo Monthly Inflow Probable Minimum Most Probable Probable Maximum 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

89 350 Navajo Monthly Releases 1000 AF Probable Minimum Most Probable Probable Maximum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

90 1700 Navajo Monthly Storage AF Probable Minimum Most Probable Probable Maximum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

91 6000 Lake Powell Monthly Inflow 1000 AF Probable Minimum Most Probable Probable Maximum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

92 1600 Lake Powell Monthly Releases Probable Minimum Most Probable Probable Maximum AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 WY WY 2007 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07

93 20000 Lake Powell Monthly Storage AF Most Probable Probable Maximum Probable Minimum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

94 Probable Minimum Most Probable Probable Maximum Lake Mead Monthly Inflow 1000 AF Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

95 1200 Lake Mead Monthly Releases AF Probable Minimum Most Probable Probable Maximum 0 Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

96 Lake Mead Monthly Storage AF Probable Minimum Most Probable Probable Maximum Oct-05 Dec-05 Feb-06 Apr-06 Jun-06 Aug-06 Oct-06 Dec-06 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 WY WY 2007

97 Fontenelle AF Monthly Storage Jan Sep 2006

98 Flaming Gorge AF Monthly Storage Jan Sept 2006

99 Blue Mesa AF Monthly Storage Jan Sep 2006

100 Navajo AF Monthly Storage Jan Sep 2006

101 Lake Powell AF Monthly Storage Jan Sept 2006

102 Lake Mead AF Monthly Storage Jan Sep 2006

103 Annual Operating Plan for Colorado River Reservoirs 2008 U.S. Department of the Interior Bureau of Reclamation

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107 TABLE OF CONTENTS INTRODUCTION...1 Authority...1 Purpose...2 Summary...2 Upper Basin Delivery...2 Lower Basin Delivery United States-Mexico Water Treaty Delivery HYDROLOGY SUMMARY AND RESERVOIR STATUS WATER SUPPLY ASSUMPTIONS...8 SUMMARY OF RESERVOIR OPERATIONS IN 2007 AND PROJECTED 2008 RESERVOIR OPERATIONS...10 Fontenelle Reservoir...11 Flaming Gorge Reservoir...11 Blue Mesa, Morrow Point, and Crystal Reservoirs (Aspinall Unit)...12 Navajo Reservoir...14 Lake Powell...16 Lake Mead...20 Lakes Mohave and Havasu...21 Bill Williams River...22 Senator Wash and Laguna Reservoirs...23 Imperial Dam...24 Gila River Flows...24 Additional Regulatory Storage...24 Yuma Desalting Plant...25 Intentionally Created Surplus...25 Intentionally Created Surplus Water Demonstration Program...26 System Conservation of Colorado River Water Demonstration Program.26 Delivery of Water to Mexico DETERMINATIONS...29 Upper Basin Reservoirs...29 Lower Basin Reservoirs United States Mexico Water Treaty...32 DISCLAIMER...33 ATTACHMENT I...34 ii 2008 AOP February 25, 2008

108 LIST OF TABLES Table 1. Reservoir Conditions on October 1, 2007 (English Units)...7 Table 2. Reservoir Conditions on October 1, 2007 (Metric Units)...7 Table 3. Projected Unregulated Inflow into Lake Powell for Water Year 2008 (English Units: maf)...9 Table 4. Projected Unregulated Inflow into Lake Powell for Water Year 2008 (Metric Units: mcm)...9 Table 5. Glen Canyon Dam Release Restrictions (Glen Canyon Dam Operating Criteria)...18 Table 6. Projected Monthly Releases from Lake Powell in Water Year 2008 Under Most Probable Inflow Conditions (English Units)...19 Table 7. Projected Monthly Releases from Lake Powell in Water Year 2008 Under Most Probable Inflow Conditions (Metric Units)...19 iii 2008 AOP February 25, 2008

109 INTRODUCTION Authority This 2008 Annual Operating Plan (AOP) was developed in accordance with Section 602 of the Colorado River Basin Project Act (Public Law ) and the Criteria for Coordinated Long-Range Operation of Colorado River Reservoirs Pursuant to the Colorado River Basin Project Act of September 30, 1968 (Operating Criteria), as amended, promulgated by the Secretary of the Interior (Secretary). This AOP implements the requirement of Section 602(b) of the Colorado River Basin Project Act that the Secretary annually prepare a report describing the actual operation under the adopted criteria [i.e., the Operating Criteria] for the preceding compact water year [i.e., from October 1 to September 30] and the projected operation of the current year. In accordance with the Colorado River Basin Project Act and the Operating Criteria, the AOP must be developed and administered consistent with applicable Federal laws, the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, Treaty Between the United States of America and Mexico, signed February 3, 1944 (1944 United States-Mexico Water Treaty), interstate compacts, court decrees, as well as the Record of Decision for Colorado River Interim Guidelines for Lower Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead (Interim Guidelines), Colorado River Water Delivery Agreement (69 Federal Register 12202, March 15, 2004), and other documents relating to the use of the waters of the Colorado River, which are commonly and collectively known as the Law of the River. The Operating Criteria and Section 602 of the Colorado River Basin Project Act mandate consultation with representatives of the Governors of the seven Basin States and such other parties as the Secretary may deem appropriate in preparing the annual plan for operation of the Colorado River reservoirs. In addition, the Grand Canyon Protection Act of 1992 (Title XVIII of Public Law ) requires consultation to include the general public and others. Accordingly, the 2008 AOP was prepared by the Bureau of Reclamation (Reclamation) in consultation with the seven Basin States Governors representatives; the Upper Colorado River Commission; Native American tribes; appropriate Federal agencies; representatives of the academic and scientific communities, environmental organizations, and the recreation industry; water delivery contractors; contractors for the purchase of Federal power; others interested in Colorado River operations; and the general public, through the Colorado River Management Work Group (CRMWG). In September 2005, Reclamation initiated a process in accordance with the National Environmental Policy Act (NEPA) to develop additional operational guidelines for Lake Powell and Lake Mead in response to the continued drought and increasing water demands on the system. A Record of Decision (ROD) adopting the Interim Guidelines was signed by the Secretary on December 13, Article I(2) of the Operating Criteria allows for revision of this 2008 AOP by June of 2008 to reflect the current hydrologic conditions. This process for revision is further described in Section 7.C of the Interim Guidelines. Any revision to the AOP may occur only through the AOP consultation process as required by applicable Federal law AOP February 25, 2008

110 Purpose The purposes of the AOP are to determine or address: (1) the projected operation of the Colorado River reservoirs to satisfy project purposes under varying hydrologic and climatic conditions; (2) the quantity of water considered necessary to be in storage in the Upper Basin reservoirs as of September 30, 2008, pursuant to Section 602(a) of the Colorado River Basin Project Act; (3) water available for delivery pursuant to the 1944 United States- Mexico Water Treaty and Minutes No. 242 and 310 of the International Boundary and Water Commission, United States and Mexico (IBWC); (4) whether the reasonable consumptive use requirements of mainstream users in the Lower Division States will be met under a Normal, Surplus, or Shortage Condition as outlined in Article III of the Operating Criteria and as implemented by the Interim Guidelines; and (5) whether water apportioned to, but unused by one or more Lower Division States exists and can be used to satisfy beneficial consumptive use requests of mainstream users in other Lower Division States as provided in the Consolidated Decree of the Supreme Court of the United States in Arizona v. California, 547 U.S. 150 (2006) (Consolidated Decree). Consistent with the above determinations and in accordance with other applicable provisions of the Law of the River, the AOP was developed with appropriate consideration of the uses of the reservoirs for all purposes, including flood control, river regulation, beneficial consumptive uses, power production, water quality control, recreation, enhancement of fish and wildlife, and other environmental factors (Operating Criteria, Article I(2)). Since the hydrologic conditions of the Colorado River Basin can never be completely known in advance, the AOP addresses the operations resulting from three different hydrologic scenarios: the probable maximum, most probable, and probable minimum reservoir inflow conditions. River operations under the plan are modified during the year as runoff predictions are adjusted to reflect existing snowpack, basin storage, and flow conditions. Summary Upper Basin Delivery. Releases from Lake Powell during water year 2008 shall be made consistent with Section 6.B (Upper Elevation Balancing Tier) in the Interim Guidelines. Consistent with Section 6.B.1 of the Interim Guidelines, the water year release from Lake Powell in 2008 shall be 8.23 maf (10,150 mcm) unless provisions in Section 6.B.3 occur. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2008, Lake Powell elevation to be greater than elevation 3,636 feet, Section 6.A (Equalization Tier) of the Interim Guidelines will govern the release of water from Lake Powell for the remainder of water year 2008 (through September 2008). Lower Basin Delivery. Under the most probable inflow scenario, downstream deliveries are expected to control the releases from Hoover Dam. Taking into account (1) the existing water storage conditions in the basin, (2) the most probable near-term water supply conditions in the basin, and (3) Section 2.B.5 of the Interim Guidelines, the Intentionally Created Surplus (ICS) Surplus Condition is the criterion governing the operation of Lake Mead for calendar year 2008 in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree AOP February 25, 2008

111 No unused apportionment for calendar year 2008 is anticipated. If any unused apportionment becomes available after adoption of this AOP, Reclamation, on behalf of the Secretary, shall allocate any such available unused apportionment for calendar year 2008 in accordance with Article II(B)(6) of the Consolidated Decree. Water may be made available for diversion pursuant to 43 CFR Part to contractors within the Lower Division States. The Secretary shall make Intentionally Created Unused Apportionment (ICUA) available to contractors in Arizona, California, or Nevada for the off-stream storage or consumptive use of water pursuant to individual Storage and Interstate Release Agreements (SIRA) and 43 CFR Part 414. In calendar year 2007, approximately maf (20.97 mcm) of ICUA water stored in Arizona was projected to be recovered for use in California, 2 by the Metropolitan Water District of Southern California (MWD). In calendar year 2008, maf (30.84 mcm) of ICUA water stored in Arizona is projected to be recovered for use in California by MWD. SNWA may propose to make from to maf (18.50 to mcm) of unused Nevada basic apportionment available for storage by MWD in The Inadvertent Overrun and Payback Policy (IOPP), which became effective January 1, 2004, will be in effect during calendar year The Colorado River Water Delivery Agreement requires payback of California overruns occurring in 2001 and 2002 as noted in Exhibit C of that document. Each district with a payback obligation under Exhibit C may at its own discretion elect to accelerate paybacks. It is anticipated that California paybacks for calendar years 2007 and 2008 will total maf (49.34 mcm) and maf (16.04 mcm), respectively. In calendar years 2007 and 2008, paybacks occurring in California result from Exhibit C obligations and IOPP overruns. In calendar years 2007 and 2008, paybacks for Arizona result only from IOPP overruns. During calendar year 2007, the scheduled Arizona paybacks were expected to total 606 ac-ft (0.75 mcm). In calendar year 2008, Arizona paybacks are projected to total 3,570 ac-ft (4.40 mcm). The Interim Guidelines ROD adopted the ICS mechanism that among other things encourages the efficient use and management of Colorado River water in the Lower Basin. The creation and delivery of ICS during the term of the Interim Guidelines is conditioned upon several implementing agreements that were executed concurrent with the Interim 1 Off-stream Storage of Colorado River Water; Development and Release of Intentionally Created Unused Apportionment in the Lower Division States: Final Rule (43 CFR Part 414; 64 Federal Register 59006, November 1, 1999) 2 Amendatory Agreement to Agreement between the Central Arizona Water Conservation District and the Metropolitan Water District of Southern California for a Demonstration Project on Underground Storage of Colorado River Water, December 1, Record of Decision for Implementation Agreement, Inadvertent Overrun and Payback Policy, and Related Federal Actions, Final Environmental Impact Statement AOP February 25, 2008

112 Guidelines ROD. ICS may be created and delivered in 2008 in compliance with the Interim Guidelines and appropriate delivery and forbearance agreements. In 2006 Reclamation implemented a demonstration program in the Lower Basin to create Intentionally Created Surplus Water (ICS Demonstration Program). The ICS Demonstration Program allowed entitlement holders to undertake extraordinary conservation activities in 2006 and 2007 to reduce their approved annual consumptive use of Colorado River water and account for that conserved water in Lake Mead. The Intentionally Created Surplus Water created and accounted for under the ICS Demonstration Program is now available for delivery pursuant to the Interim Guidelines and implementing agreements. In 2006 Reclamation implemented the System Conservation of Colorado River Water Demonstration Program (SC Demonstration Program) in the Lower Basin which allows entitlement holders to participate in voluntary conservation to conserve a portion of their approved annual consumptive use of Colorado River water in exchange for appropriate compensation provided by Reclamation. The water conserved (SC Water) would be retained in Lake Mead to assist in providing an interim, supplemental source of water to replace the drainage water from the Wellton-Mohawk Irrigation and Drainage District that is bypassed to the Cienega de Santa Clara and the reject stream from operation of the Yuma Desalting Plant United States-Mexico Water Treaty Delivery. A volume of maf (1,850 mcm) of water will be available to be scheduled for delivery to Mexico during calendar year 2008 in accordance with Article 15 of the 1944 United States-Mexico Water Treaty and Minutes No. 242 and 310 of the IBWC AOP February 25, 2008

113 2007 HYDROLOGY SUMMARY AND RESERVOIR STATUS Below average streamflows were observed in the Colorado River Basin during Unregulated 4 inflow to Lake Powell in water year 2007 was maf (10,150 mcm), or 68 percent of the 30 year average 5 which is maf (14,880 mcm). Unregulated inflow to Flaming Gorge, Blue Mesa, and Navajo Reservoirs was 43, 90, and 98 percent of average, respectively. Runoff from numerous precipitation events reached the Upper Colorado River Basin in October 2006 (the first month of water year 2007). These precipitation events were particularly heavy in the regions surrounding Lake Powell. Runoff in the San Juan, Dirty Devil, and San Rafael Rivers was very high in response to these storm events. Lake Powell increased in elevation by 6.2 feet (1.9 meters) during the month. Aggregate precipitation in the Upper Colorado River Basin was nearly 200 percent of normal in October Basin hydrologic conditions trended drier beginning in November This trend continued through the winter months. In almost all areas of the Upper Colorado River Basin, snowpack remained below average throughout the winter of Basinwide snowpack above Lake Powell on March 1, 2007, was 81 percent of average. At that time, the projected April through July inflow to Lake Powell was 71 percent of average. Temperatures in the Colorado River Basin were much above average and precipitation was below average in March Normally, mountain snowpack continues to build in the month of March. However, in March 2007 there was a net loss of snow in most of the Colorado River Basin with a significant reduction in the water supply projections. In April 2007, the April through July inflow projection to Lake Powell was reduced by 21 percentage points to 50 percent of average. Observed April through July unregulated inflow to Lake Powell was maf (5,000 mcm), or 51 percent of average. The Colorado River Basin experienced five consecutive years of extreme drought during water years 2000 through Unregulated inflow into Lake Powell during this five-year period was only 62, 59, 25, 51, and 49 percent of average, respectively. These years of very low inflow resulted in significant drawdown of Colorado River reservoirs with total system storage decreasing from 92 percent of capacity on October 1, 1999, to 50 percent of capacity on October 1, Hydrologic conditions improved in 2005 with above average inflow to Lake Powell (105 percent of average) and record-breaking tributary flows in the Lower Colorado River Basin. Lower Basin tributary inflow into Lake Mead for water year 2005 totaled approximately maf (1,088 mcm), or 253 percent of average. Colorado River reservoirs gained 5.10 maf (6,290 mcm) of storage in water year Drier hydrologic conditions returned in Unregulated inflow to Lake Powell in water year 2006 was 71 percent of average. Inflow to all major Colorado River reservoirs was below average in Unregulated inflow adjusts for the effects of operations at upstream reservoirs. It is computed by adding the change in storage and the evaporation losses from upstream reservoirs to the observed inflow. Unregulated inflow is used because it provides an inflow time series that is not biased by upstream reservoir operations. 5 Inflow statistics throughout this document will be compared to the 30-year average, , unless otherwise noted AOP February 25, 2008

114 Inflow to Lake Powell has been below average in seven out of the past eight years. While drought conditions eased in 2005, and the inflow in 2006 and 2007 was not as low as what occurred in 2000 through 2004, drought conditions in the Colorado River Basin persist. Provisional calculations of natural flow for the Colorado River at Lees Ferry, Arizona, show that the average flow over the last eight water years ( , inclusive) was the lowest eight-year average in 100 years of record keeping on the Colorado River. Runoff from numerous precipitation events also reached the Lower Colorado River Basin in October 2006, associated with heavy rainfall in regions surrounding Lake Powell. Runoff from the Paria River, Little Colorado River, and Virgin River was also high in response to these storm events. Lake Mead increased in elevation by 1.0 ft (0.31 m) in the first two weeks of October Although tributary inflows in the Lower Colorado River Basin were exceptionally high during water year 2005 and October 2006, overall tributary inflows were below average for water year Drought conditions persisted for water year 2007 throughout the Lower Basin and the southwestern United States. 6 Abnormally dry to extreme drought conditions persisted throughout Arizona, contributing to 79 percent of average precipitation being recorded in the Gila River Basin. During water year 2007 no tributary inflow from the Gila River reached the mainstream of the Colorado River. 7 Tributary inflow from the Little Colorado River for water year 2007 also reflected severe drought conditions in the State of Arizona. Tributary inflow from the Little Colorado for water year 2007 totaled maf (136.9 mcm), or 62 percent of the long-term 8 average. Tributary inflow from the Bill Williams River into the mainstream totaled maf (30.84 mcm) for water year 2007, or 25 percent of the long-term average. Tributary inflow from the Virgin River for water year 2007 was estimated at being near average, totaling maf (202.3 mcm), or 95 percent of the long-term average. 9 Below average inflow to Colorado River reservoirs in 2007 resulted in a net loss in Colorado River total system storage. Reservoir storage in Lake Powell experienced a nominal increase during water year 2007, increasing by maf (16.04 mcm). Storage in Lake Mead declined by maf (1,705 mcm) during water year At the beginning of water year 2007, Colorado River total system storage was 56 percent of capacity. As of September 30, 2007, total system storage was 54 percent of capacity, a decrease of approximately maf (1,727 mcm). 6 From the US Drought Monitor website: 7 Tributary inflow from the Gila River to the mainstream is very sporadic. These flows occur very seldom and when they do they are typically of high magnitude. 8 The basis for the long-term average is natural flow data from 1906 to Additional information regarding natural flows may be found at 9 Water year estimates for the Virgin River are based on projections from a partial water year record due to gage outage. The partial water year record for the Virgin River gage is from October 2006 to March AOP February 25, 2008

115 Tables 1 and 2 list the October 1, 2007, reservoir vacant space, live storage, water elevation, percent of capacity, change in storage, and change in water elevation during water year Table 1. Reservoir Conditions on October 1, 2007 (English Units) Reservoir Vacant Space Live Storage Water Elevation Percent of Capacity Change in Storage * Change in Elevation * (maf) (maf) (ft) (%) (maf) (ft) Fontenelle , Flaming Gorge , Blue Mesa , Navajo , Lake Powell , Lake Mead , Lake Mohave Lake Havasu Totals * From October 1, 2006, to September 30, Table 2. Reservoir Conditions on October 1, 2007 (Metric Units) Reservoir Vacant Space Live Storage Water Elevation Percent of Capacity Change in Storage * Change in Elevation * (mcm) (mcm) (m) (%) (mcm) (m) Fontenelle , Flaming Gorge 846 3,779 1, Blue Mesa , Navajo 228 1,863 1, Lake Powell 15,283 14,715 1, Lake Mead 16,492 15, , Lake Mohave 327 1, Lake Havasu Totals 33,601 39, ,727 * From October 1, 2006, to September 30, AOP February 25, 2008

116 2008 WATER SUPPLY ASSUMPTIONS For 2008 operations, three reservoir unregulated inflow scenarios were developed and analyzed and are labeled as probable maximum, most probable, and probable minimum. The attached graphs show these inflow scenarios with associated release patterns and endof-month contents for each reservoir. Although there is considerable uncertainty associated with streamflow forecasts and reservoir operating plans made a year in advance, these projections are valuable in analyzing probable impacts on project uses and purposes. The National Weather Service s Colorado Basin River Forecast Center developed the inflow for the probable maximum (10 percent exceedance), most probable (50 percent exceedance), and probable minimum (90 percent exceedance) inflow scenarios in 2008 using the Ensemble Streamflow Prediction (ESP) model. ESP accounts for antecedent streamflows as well as current soil moisture levels with a continuous soil moisture accounting model known as the Sacramento Soil Moisture Accounting Model. The most probable unregulated inflow for Lake Powell in water year 2008 is 9.77 maf (12,050 mcm), or 81 percent of average. The probable minimum unregulated inflow to Lake Powell in water year 2008 is 4.10 maf (5,060 mcm), or 34 percent of average. The probable maximum unregulated inflow is maf (20,350 mcm), or 137 percent of average. The three inflow scenarios for Lake Powell are shown in Tables 3 and 4. Side inflows from Lake Powell to Lake Mead, Lake Mead to Lake Mohave, and Lake Mohave to Lake Havasu are forecasted using historic data over the five-year period of January 2002 through December 2006, inclusive. The last five years of historic data are being used to best represent most recent hydrologic conditions for operational forecasts. Most probable forecasted side inflows into each reach are the arithmetic mean of the fiveyear record. The probable maximum and probable minimum forecasts for the reach between Lake Powell and Lake Mead are the 10% exceedance and 90% exceedance, respectively, of the five-year record. The most probable side inflow into Lake Mead during water year 2008 is maf (1,098 mcm). The probable minimum side inflow into Lake Mead is maf (485 mcm). The probable maximum side inflow is maf (1,976 mcm). The monthly volumes of inflow resulting from these assumptions were input into Reclamation s monthly reservoir simulation model and used to plan reservoir operations for Starting with October 1, 2007, reservoir storage conditions, the monthly releases for each reservoir were adjusted until release and storage levels best accomplished project purposes. Graphs of the projected 2008 inflows, releases, and storages for each hydrologic scenario are presented in Attachment I AOP February 25, 2008

117 Table 3. Projected Unregulated Inflow into Lake Powell for Water Year 2008 (English Units: maf) 10 Time Period Probable Maximum Most Probable Probable Minimum 10/07 12/ /08 3/ /08 7/ /08 9/ /08 12/ WY CY Table 4. Projected Unregulated Inflow into Lake Powell for Water Year 2008 (Metric Units: mcm) Time Period Probable Maximum Most Probable Probable Minimum 10/07 12/07 2,640 1, /08 3/08 2,580 1, /08 7/08 13,260 7,920 3,300 8/08 9/08 1,870 1, /08 12/08 1,790 1,790 1,790 WY ,350 12,060 5,060 CY ,490 12,360 6, All values in Tables 3 and 4 are forecasted inflows with the exception of the values for 10/08 12/08. The values for this period are the average unregulated inflow from The calendar year totals in Tables 3 and 4 also reflect the average values for the 10/08 12/08 time period AOP February 25, 2008

118 SUMMARY OF RESERVOIR OPERATIONS IN 2007 AND PROJECTED 2008 RESERVOIR OPERATIONS The regulation of the Colorado River has had effects on aquatic and riparian resources. Controlled releases from dams have modified temperature, sediment load, and flow patterns, resulting in increased productivity of some introduced aquatic resources and the development of economically significant sport fisheries. However, these same releases have detrimental effects on endangered and other native species. Operating strategies designed to protect and enhance aquatic and riparian resources have been established at several locations in the Colorado River Basin. In the Upper Basin, public stakeholder work groups have been established at Fontenelle Dam, Flaming Gorge Dam, the Aspinall Unit, and Navajo Dam. These work groups provide a public forum for dissemination of information regarding ongoing and projected reservoir operations throughout the year and allow stakeholders the opportunity to provide information and feedback with respect to ongoing reservoir operations. At Glen Canyon Dam, the Glen Canyon Dam Adaptive Management Work Group (AMWG), a Federal Advisory Committee Act (FACA) committee, was established in Since its inception, the AMWG has met regularly to analyze and make recommendations to the Secretary regarding research and monitoring programs in the Grand Canyon as well as experimental modifications to dam operations. 11 Modifications to planned operations may be made based on changes in forecast conditions or other relevant factors. Consistent with the Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin (Upper Colorado Recovery Program), 12 the San Juan River Basin Recovery Implementation Program (San Juan Recovery Program), 13 Section 7 consultations under the Endangered Species Act (ESA), and other downstream concerns, modifications to monthly operation plans may be based on other factors in addition to changes in streamflow forecasts. Decisions on spring peak releases and downstream habitat target flows may be made midway through the runoff season. Reclamation will conduct meetings with the U.S. Fish and Wildlife Service (Service), other Federal agencies, representatives of the Basin States, and with public stakeholder work groups to facilitate the discussions necessary to finalize site-specific operations plans. In 1995 Reclamation and the Service formed a partnership with other Federal, state, and local public agencies and private organizations to develop the Lower Colorado River Multi- Species Conservation Program (LCR MSCP). This program permits both non-federal and Federal parties to participate in and address ESA compliance requirements under Sections 7 and 10 of the ESA. In April 2005 the Secretary signed the Record of Decision to begin implementation of the LCR MSCP Additional information on the AMWG can be found at 12 Additional information on the Upper Colorado Recovery Program can be found at 13 Additional information on the San Juan Recovery Program can be found at 14 Additional information on the LCR MSCP can be found at AOP February 25, 2008

119 The following paragraphs discuss the 2007 and most probable projected 2008 operation of each of the reservoirs with respect to applicable provisions of compacts, the Consolidated Decree, statutes, regulations, contracts, and instream flow needs for maintaining or improving aquatic resources where appropriate. Fontenelle Reservoir Hydrologic conditions in water year 2007 in the Upper Green River Basin were extremely poor when compared to the historic record for the reservoir. The April through July inflow to Fontenelle Reservoir during water year 2007 was maf (361 mcm), which was only 34 percent of average. While drought conditions were present throughout the Colorado River Basin, drought conditions were most severe in the Upper Green River Basin when compared to other sub-basins in the Upper Colorado River Basin. Inflow to Fontenelle Reservoir has been below average for 8 consecutive years. Fontenelle Reservoir did not fill in 2007 and bypass releases were not necessary in order to accommodate the spring runoff. Inflow peaked at 3,100 cfs (88 cms) on May 24, Releases from Fontenelle Reservoir were maintained at approximately 800 cfs (23 cms) through the spring runoff period. The peak elevation of Fontenelle Reservoir during water year 2007 was 6,490.0 feet (1,978.1 meters) above sea level which occurred on July 2, This elevation is 16.0 feet (4.9 meters) below the spillway crest elevation. The most probable April through July inflow to Fontenelle Reservoir during water year 2008 is maf (728 mcm). This volume far exceeds maf (426 mcm), the storage capacity of Fontenelle Reservoir. For this reason, the most probable and probable maximum inflow scenarios require releases during the spring that exceed the capacity of the powerplant to avoid uncontrolled spills from the reservoir. It is very likely that Fontenelle Reservoir will fill during water year In order to minimize high spring releases and to maximize downstream water resources and power production, the reservoir will most likely be drawn down to about elevation 6,468 feet (1,971 meters) by early April 2008, which is five feet (1.5 meters) above minimum power pool, and corresponds to a volume of maf (137 mcm) of live storage. Flaming Gorge Reservoir Inflow to Flaming Gorge Reservoir during water year 2007 was extremely low. Unregulated inflow in water year 2007 was maf (918 mcm), which is 43 percent of average. Flaming Gorge Reservoir did not fill during water year On October 1, 2006, the beginning of water year 2007, the reservoir elevation was 6,024.2 feet (1,836.2 meters). The reservoir elevation decreased during water year 2007 and ended water year 2007 (on September 30, 2007) at an elevation of 6,022.4 feet (1,835.6 meters). The water year ending reservoir elevation was 17.6 feet (5.4 meters) below the full pool elevation of 6,040.0 feet (1,841.0 meters) which corresponds to an available storage space of maf (846 mcm). Reclamation operated Flaming Gorge Dam in compliance with the Flaming Gorge Record of Decision (Flaming Gorge ROD) in The hydrologic conditions during the spring of 2007 were designated as Moderately Dry. Reclamation convened a technical working group, comprised of Service, Western Area Power Administration (Western), and AOP February 25, 2008

120 Reclamation personnel, which proposed that the Green River measured at the Jensen, Utah stream gauge should be managed to maintain flows at or above 8,300 cfs (235 cms) for 7 days or more during the peak flows of the Yampa River. Releases from Flaming Gorge Reservoir were increased to powerplant capacity of 4,450 cfs (126 cms) on May 14, 2007, in anticipation of peak flows on the Yampa River. On May 17, 2007, as a result of releases from Flaming Gorge Dam and flows on the Yampa River, the flows in the Green River at Jensen reached 12,800 cfs (362 cms). Releases were maintained at powerplant capacity until May 20, 2007, which was the 7 th day of flows in the Green River above 8,300 cfs (235 cms). Flows in the Green River at Jensen remained above 8,300 cfs (235 cms) until May 26, 2007 (12 days). Releases from Flaming Gorge Reservoir were reduced by 350 cfs (10 cms) per day beginning on May 21, Releases were maintained at 1,150 cfs (33 cms) during June Releases were reduced to 800 cfs (23 cms) in July 2007 and remained at this level for the duration of calendar year During water year 2008, Flaming Gorge Dam will continue to be operated in accordance with the Flaming Gorge ROD. High spring releases are scheduled to occur in 2008, timed with the Yampa River s spring runoff peak flow, followed by lower summer and autumn base flows. Under the most probable scenario, releases in the winter and early spring of 2008 will be 800 cfs (23 cms). The Upper Colorado Recovery Program, in coordination with Reclamation, the Service, and Western, is conducting studies associated with flood plain inundation. Such studies include: improving connectivity of flood plain habitats, identifying ways to improve entrainment of larval razorback suckers into floodplain habitats, maintaining the river channel, restoring natural variability of the river system, and analyzing possibilities for meeting the goals of the Flow and Temperature Recommendations at lower peak flow levels where feasible. Blue Mesa, Morrow Point, and Crystal Reservoirs (Aspinall Unit) Below average snowpack conditions prevailed in the Gunnison Basin during water year Snow measurement sites in the basin reported below average moisture throughout the winter and into the spring of The April through July unregulated runoff into Blue Mesa Reservoir in 2007 was maf (630 mcm), or 71 percent of average, and occurred earlier than normal. Water year 2007 unregulated inflow into Blue Mesa Reservoir was maf (1,100 mcm), or 90 percent of average. Blue Mesa Reservoir nearly filled in 2007 reaching a peak elevation of 7,514.7 feet (2,290.5 meters) on July 2, 2007, 4.7 feet (1.4 meters) from full pool. Storage in Blue Mesa Reservoir increased during water year 2007 by maf (25 mcm). Storage in Blue Mesa Reservoir on September 30, 2007, was maf (847 mcm), or 83 percent of capacity. Releases from Aspinall Unit reservoirs in 2007 were below normal levels. Releases from the Aspinall Unit provided for a flow of 900 to 1,500 cfs (11.3 to 14.2 cms) from October 1, 2006, to January 15, 2007, in the Gunnison River through the Black Canyon (below the Gunnison Tunnel). In January, releases began to be decreased in response to decreasing forecasted inflow and reached 800 cfs in March Beginning the last week of March, Crystal releases were increased as the diversions through the Gunnison Tunnel increased. Water year 2007 powerplant bypasses were approximately maf (48 mcm) at Crystal AOP February 25, 2008

121 Dam. These bypass releases occurred because the powerplant was shut down for maintenance during parts of January and February On August 16, 1995, Memorandum of Agreement (MOA) No R1760 was signed by Reclamation, the Service, and the Colorado Water Conservation Board. The purpose of the MOA was to provide water to the Redlands Fish Ladder, assure at least 300 cfs (8.5 cms) of flow in the 2-mile reach of the Gunnison River between the Redlands Fish Ladder and the confluence of the Gunnison and Colorado Rivers (2-mile reach), and to benefit Colorado River Basin endangered fish. This MOA was extended for an additional five years on June 30, A key provision of the MOA requires that the parties adopt a plan to share water shortages in dry years, when total storage at Blue Mesa Reservoir is projected to drop below 0.40 maf (493 mcm) by the end of the calendar year. However, the MOA was not renewed in Reclamation intends to operate the Aspinall Unit to meet the intent of the MOA if water supplies are available. While deliveries of 100 cfs (2.8 cms) to the Redlands Fish Ladder can be protected under Colorado water law, absent the MOA, the additional releases for the benefit of the 2-mile reach cannot. Releases from the Aspinall Unit combined with runoff from intervening tributaries resulted in at least 276 cfs (7.8 cms) being available for the fish ladder and 2-mile reach of the Gunnison River in On January 17, 2001, the United States filed an application to quantify the Federal reserved water right decreed to the Black Canyon of the Gunnison National Monument. The water right is for flows in the Gunnison River through the Black Canyon of the Gunnison National Park which is downstream of the Gunnison Tunnel and downstream of the Aspinall Unit. On April 2, 2003, the Department of the Interior and the State of Colorado reached agreement regarding water for the Park. Under the 2003 agreement, an amended water right application was filed by the United States for the National Park Service for 300 cfs (8.5 cms) with a 1933 priority date. In a separate action, the Colorado Water Conservation Board filed, under the State of Colorado instream flow program, for additional flows in excess of those required to fulfill the purposes of the Aspinall Unit (with a 2003 priority date) to provide for protection of additional water resources for the Park. The 2003 amended Federal reserved water right application was challenged in United States District Court in Colorado. On September 11, 2006, the District Court set aside the 2003 agreement. Currently, the parties to the water rights case are engaged in formal mediation. In July 2003, a final report titled, Flow Recommendations to Benefit Endangered Fishes in the Colorado and Gunnison Rivers (Flow Recommendations for the Colorado and Gunnison Rivers) was published by the Upper Colorado Recovery Program. The report compiled and summarized the results of endangered fish research in the Gunnison and Upper Colorado Rivers under the Upper Colorado Recovery Program. The report presents flow recommendations for two different river reaches: one for the lower Gunnison River between Delta and Grand Junction, Colorado, as measured at Whitewater (Gunnison River near Grand Junction gage); and the other for the Colorado River downstream of the Gunnison River confluence as measured at the Colorado-Utah State line. In January 2004, Reclamation published a Notice of Intent to prepare an Environmental Impact Statement (EIS). The purpose of Reclamation s proposed action is to operate the Aspinall Unit to avoid jeopardy to endangered species while maintaining the congressionally authorized Aspinall Unit purposes. Public scoping meetings were held in February 2004 and cooperating agency meetings were held in 2005 and Reclamation will develop AOP February 25, 2008

122 alternatives to address the Flow Recommendations for the Colorado and Gunnison Rivers. Difficulties in resolution of the reserved water right for the Black Canyon of the Gunnison National Park have delayed progress on the EIS. A draft EIS is likely to be released in For water year 2008, the Aspinall Unit will be operated to conserve storage while meeting downstream delivery requirements, consistent with authorized project purposes. Under normal conditions, the minimum release objectives of the Aspinall Unit are to honor the delivery requirements of the Uncompahgre Valley Project, and other senior water rights downstream, to the extent possible to maintain a year round minimum flow of at least 300 cfs (8.5 cms) in the Gunnison River through the Black Canyon, and to the extent possible maintain a minimum flow of 300 cfs (8.5 cms) in the 2-mile reach below the Redlands Diversion Dam during the months of July through October. In dry years, the 300 cfs (8.5 cms) flow through the canyon and the 2-mile reach can be reduced. In 2008, under the most probable inflow conditions, flows through the Black Canyon of the Gunnison National Park will be above the 300 cfs (8.5 cms) minimum release objective during the summer months. Consideration shall be given to the trout fishery in the Black Canyon and Gunnison Gorge and recreational interests consistent with project purposes. Releases during 2008 will be planned to minimize fluctuations in the daily and monthly flows in the Gunnison River below the Gunnison Tunnel diversion. Under the probable minimum inflow scenario, Blue Mesa Reservoir would not fill in Under the most probable and probable maximum inflow scenarios, Blue Mesa Reservoir is expected to fill in Navajo Reservoir Inflow to Navajo Reservoir in 2007 was near the 30-year average. Water year 2007 unregulated inflow was maf (1353 mcm), or 98 percent of average. A significant portion of the water year inflow occurred in October 2006 when heavy rains in the San Juan River Basin resulted in inflow being 380 percent of average for the month. The April through July unregulated inflow into Navajo Reservoir in water year 2007 was maf (629 mcm), or 76 percent of average. Unregulated inflow to Navajo Reservoir in water years 2000, 2001, 2002, 2003, 2004, 2005 and 2006 was 42, 93, 11, 44, 72, 136 and 62 percent of average, respectively. Navajo Reservoir reached a peak water surface elevation of 6,080.3 feet (1,853.3 meters) on June 21, 2007, 4.7 feet (1.4 meters) from full pool. The water surface elevation at Navajo Reservoir on September 30, 2007, was 6,072.1 feet (1,850.8 meters), with reservoir storage at 89 percent of capacity. The final report titled, Flow Recommendations for the San Juan River (San Juan Flow Recommendations), which outlines flow recommendations for the San Juan River below Navajo Dam, was completed by the San Juan Recovery Program in May 1999 after a sevenyear research period. The purpose of the report is to provide flow recommendations for the San Juan River that promote the recovery of the endangered Colorado pikeminnow and razorback sucker, maintain important habitat for these two species as well as the other native species, and provide information for the evaluation of continued water development in the AOP February 25, 2008

123 basin. These flow recommendations are under review through the San Juan Recovery Program and may be revised in the future. In 2006, Reclamation completed a NEPA process on the implementation of operations at Navajo Dam that meet the San Juan Flow Recommendations, or a reasonable alternative to them. A Notice of Intent to prepare an EIS was published on October 1, 1999, in the Federal Register. In January 2006, the Service issued a non-jeopardy biological opinion for the operations of Navajo Dam to meet the San Juan Flow Recommendations, or a reasonable alternative. The Navajo Reservoir Operations Final EIS was issued on April 20, The ROD for the Navajo Reservoir Operations Final EIS was signed by the Regional Director of Reclamation s Upper Colorado Region on July 31, The San Juan Flow Recommendations called for making a 13-day spring peak release of 5,000 cfs (142 cms) from Navajo Reservoir in In anticipation of a potential early spring runoff, the peak release was started earlier in 2007 than in previous years. Releases were increased beginning on April 30, A release rate of 5,000 cfs (142 cms) was reached on May 3, 2007, and was maintained until May 17, Releases were reduced to a flow of 1,250 cfs (35 cms) in late May and remained at this level though the end of June A base summer release rate of 750 cfs (21.2 cms) was implemented on July 1, In 2007, a group of water users developed a two-year agreement to limit their water use to the rates/volumes indicated in the agreement for the years The Recommendations for Administration and Operation of the San Juan River was similar to the agreements that were developed in 2003, 2004, 2005, and Ten major water users (the Jicarilla Apache and Navajo Nations, Hammond Conservancy District, Public Service Company of New Mexico, City of Farmington, Arizona Public Service Company, BHP- Billiton, Bloomfield Irrigation District, Farmers Mutual Ditch, and Jewett Valley Ditch) endorsed the recommendations which included limitations on diversions for , criteria for determining a shortage, and shortage-sharing requirements in the event of a water supply shortfall, including sharing of shortages between the water users and the flow demands for endangered fish habitat. In addition to the ten major water users, the New Mexico Interstate Stream Commission, the Bureau of Indian Affairs, the Service, and the San Juan Recovery Program all provided input to the recommendations. The recommendations were acknowledged by Reclamation and the New Mexico State Engineer for reservoir operation and river administration purposes. During water year 2008, Navajo Reservoir will be operated in accordance with the Navajo Reservoir Operations ROD. Navajo Reservoir storage levels are expected to be above average in 2008 under the most probable and probable maximum inflow scenarios. Releases from the reservoir will likely be reduced to 500 cfs (14 cms) in December 2007 and remain at that level through the winter. Under the most probable inflow condition in 2008, a 21-day spring peak release of 5,000 cfs (142 cms), as described in the San Juan Flow Recommendations, is likely to occur AOP February 25, 2008

124 Lake Powell Reservoir storage in Lake Powell remains low (49 percent of capacity on September 30, 2007) due to effects of continuing drought in the Colorado River Basin. Lake Powell storage was 97 percent of capacity in July Extreme drought conditions were observed in the Colorado River Basin for five consecutive years (water years ) with Lake Powell storage declining during this period. Lake Powell storage on September 30, 2004, was only 38 percent of capacity. Inflow was above average in 2005 and Lake Powell gained 2.77 maf (3,420 mcm) of storage during the water year. Below average inflow conditions returned in 2006 and continued in Lake Powell began water year 2007 with maf (14,700 mcm) of water in storage (49 percent of capacity). Water year 2007 unregulated inflow to Lake Powell was maf (10,150 mcm), or 68 percent of average. As water year 2007 ended on September 30, 2007, Lake Powell storage was maf (14,720 mcm), or 49 percent of capacity. Due to continued low reservoir storage at Lake Powell, and storage in Lake Powell being less than Lake Mead, releases from Glen Canyon Dam in 2007 were scheduled to maintain the minimum release objective from Lake Powell of 8.23 maf (10,150 mcm) in accordance with Article II(2) of the Operating Criteria. Forecasted inflow to Lake Powell combined with observed reservoir storage in Lake Powell in 2007 was not sufficient to trigger storage equalization releases from Lake Powell to Lake Mead. The total release from Lake Powell in water year 2007 was maf (10,150 mcm). April through July unregulated inflow to Lake Powell in water year 2007 was maf (5,000 mcm), or 51 percent of average. Lake Powell reached a seasonal peak elevation of 3,611.7 feet (1,100.8 meters), 88.3 feet (26.9 meters) from full pool, on June 25, On September 30, 2007, the water surface elevation of Lake Powell was 3,601.9 feet (1,097.8 meters), 98.1 feet (29.9 meters) from full pool. Releases from Lake Powell during water year 2008 shall be made consistent with Section 6.B (Upper Elevation Balancing Tier) in the Interim Guidelines. Consistent with Section 6.B.1 of the Interim Guidelines, the water year release from Lake Powell in 2008 shall be 8.23 maf (10,150 mcm) unless provisions in Section 6.B.3 occur. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2008, Lake Powell elevation to be greater than elevation 3,636 feet, Section 6.A (Equalization Tier) of the Interim Guidelines will govern the release of water from Lake Powell for the remainder of water year 2008 (through September 2008). Under the most probable and probable minimum inflow scenarios, releases of 8.23 maf (10,150 mcm) would be made from Lake Powell in water year Under the probable maximum inflow condition, an annual release of approximately maf (14,200 mcm) would be required to equalize storage between Lake Powell and Lake Mead on September 30, Under the most probable inflow in 2008, the projected water surface elevation at Lake Powell on September 30, 2008, will be 3,609.9 feet (1,100.3 meters) with maf (15,690 mcm) of storage (52 percent of capacity) AOP February 25, 2008

125 Reclamation published a Notice of Intent in the Federal Register (71 Federal Register 74556, December 12, 2006) in December 2006 announcing Reclamation s intent to prepare an EIS on the adoption of a long-term experimental plan for the operation of Glen Canyon Dam and other associated management activities. The Long-Term Experimental Plan (LTEP) EIS was initiated to consider dam operations, potential modifications to Glen Canyon Dam intake structures, and other potential management actions such as removal of non-native fish species in the Colorado River below Glen Canyon Dam. The LTEP EIS builds on a decade of scientific experimentation and monitoring that has taken place as part of the Glen Canyon Dam Adaptive Management Program (AMP), and builds on the knowledge gained by experiments, operations, and management actions taken under the AMP. The NEPA process for this EIS evaluates the implications and impacts of each of the alternatives on all of the purposes and benefits of Glen Canyon Dam as well as on downstream resources. Reclamation conducted public scoping meetings on January 4 and 5, 2007, in Phoenix and Salt Lake City, respectively. A scoping report was published on March 30, Subsequently, in December 2007, Reclamation re-initiated ESA Section 7 consultation with the Service on the operation of Glen Canyon Dam. This consultation also includes a proposed high flow test in March Steady flows in the months of September and October, for a five-year period, are also proposed in this consultation. After completion of the appropriate environmental compliance documentation by Reclamation on these actions, Reclamation will reassess the proposed long-term experimental plan and any other associated environmental compliance activities. In March 2008, a high flow test may be implemented. As a result of information resulting from scientific monitoring and research activities and stakeholder discussions in the Glen Canyon Dam Adaptive Management Program, Reclamation has proposed a 2008 high flow test. The dam release characteristics of such a test would be identical to the test conducted in November 2004 (with a maximum release of about 41,500 cfs [1,175 cms] for 60 hours), but under much more highly enriched fine sediment conditions, a unique situation during the last 10 years. The purpose of this test would be to determine the effectiveness of rebuilding and reworking sandbar deposits and backwaters in Marble and Grand Canyons. A final decision on whether to conduct such a test is expected to be made in February 2008, after appropriate environmental compliance actions are complete. The annual volume of water released from Lake Powell for water year 2008 would not change as a result of the high flow test. In 2008, scheduled maintenance activities at Glen Canyon Dam powerplant will require that one or more of the eight generating units periodically be offline. Coordination between Reclamation offices in Salt Lake City, Utah, and Page, Arizona, will take place in the scheduling of maintenance activities to minimize impacts, including those on potential experimental releases. Because of less than full storage conditions in Lake Powell resulting from drought in the Colorado River Basin, releases for dam safety purposes are highly unlikely in If implemented, releases greater than powerplant capacity would be made consistent with the 1956 Colorado River Storage Project Act, the 1968 Colorado River Basin Project Act, and the 1992 Grand Canyon Protection Act. Reservoir releases in excess of powerplant capacity AOP February 25, 2008

126 required for dam safety purposes during high reservoir conditions may be used to accomplish the objectives of the beach/habitat-building flow according to the terms contained in the Glen Canyon Dam ROD and as published in the Glen Canyon Dam Operating Criteria (62 Federal Register 9447, March 3, 1997). Daily and hourly releases in 2008 will be made according to the parameters of the ROD for the Glen Canyon Dam Final Environmental Impact Statement (GCDFEIS) and the Glen Canyon Dam Operating Criteria, as shown in Table 5. Exceptions to these parameters may be made during power system emergencies, during experimental releases, or for purposes of humanitarian search and rescue. Table 5. Glen Canyon Dam Release Restrictions (Glen Canyon Dam Operating Criteria) Parameter (cfs) (cms) Conditions Maximum Flow 15 25, Minimum Flow 5, :00 pm to 7:00 am 8, :00 am to 7:00 pm Ramp Rates Ascending 4, per hour Descending 1, per hour Daily Fluctuations 16 5,000 / 8, / Releases from Lake Powell in water year 2008 will continue to reflect consideration of the uses and purposes identified in the authorizing legislation for Glen Canyon Dam. Powerplant releases will reflect criteria based on the findings, conclusions, and recommendations made in the ROD for the GCDFEIS pursuant to the Grand Canyon Protection Act of 1992 and appropriate NEPA documentation regarding experimental flows. 15 May be exceeded during beach/habitat-building flows, habitat maintenance flows, or when necessary to manage above average hydrologic conditions. 16 Daily fluctuations limit is 5,000 cfs (141.6 cms) for months with release volumes less than maf (740 mcm); 6,000 cfs (169.9 cms) for monthly release volumes of to maf (740 to 987 mcm); and 8,000 cfs (226.6 cms) for monthly release volumes over maf (990 mcm) AOP February 25, 2008

127 Projected monthly releases under the most probable inflow scenario, with and without the proposed high flow experiment, for water year 2008 are displayed in Table 6 and Table 7. Table 6. Projected Monthly Releases from Lake Powell in Water Year 2008 Under Most Probable Inflow Conditions (English Units) 17 Month Monthly Release without the High Flow Experiment (maf) Monthly Release with the High Flow Experiment (maf) October November December January February March April May June July August September Table 7. Projected Monthly Releases from Lake Powell in Water Year 2008 Under Most Probable Inflow Conditions (Metric Units) Month Monthly Release without the High Flow Experiment (mcm) Monthly Release with the High Flow Experiment (mcm) October November December January February March April May June July August September The ten-year total flow of the Colorado River at Lee Ferry 18 for water years 1998 through 2007 is 93.2 maf (115,000 mcm). This total is computed as the sum of the flow of the Colorado River at Lees Ferry, Arizona and the Paria River at Lees Ferry, Arizona, surfacewater discharge stations, which are operated and maintained by the United States Geological Survey. 17 Modifications to projected monthly releases from Lake Powell would be made based on changes in forecast conditions or other relevant factors. 18 A point in the mainstream of the Colorado River one mile below the mouth of the Paria River AOP February 25, 2008

128 Lake Mead For calendar year 2007, the Partial Domestic Surplus Condition was the criterion governing the operation of Lake Mead in accordance with Article III(3)(b) of the Operating Criteria, Article II(B)(2) of the Consolidated Decree, and Section 2(B)(1) of the Interim Surplus Guidelines. It should be noted, however, that the projected releases in 2007 reflected demand under the Normal Condition for MWD, Central Arizona Project (CAP), and SNWA, per their request. This did not, however, preclude MWD, CAP, and SNWA from requesting Partial Domestic Surplus water in calendar year A volume of maf (1,852 mcm) of water was scheduled for delivery to Mexico in accordance with Article 15 of the 1944 United States-Mexico Treaty and Minutes No. 242 and 310 of the International Boundary and Water Commission. Lake Mead began water year 2007 on October 1, 2006, at elevation 1,125.4 feet (343.0 meters), with maf (17,130 mcm) in storage, which is 54 percent of the conservation capacity of maf (31,923 mcm). Lake Mead s elevation increased to elevation 1, feet (344.3 meters) by the end of January After January 2007, Lake Mead steadily declined and ended the water year on September 30, 2007, at an elevation of 1, feet (338.7 meters), with maf (15,430 mcm) in storage (48 percent of capacity). The total release from Lake Mead through Hoover Dam during water year 2007 was maf (11,659 mcm). The total release from Lake Mead through Hoover Dam during calendar year 2007 is projected to be maf (11,560 mcm). Consumptive use from Lake Mead during calendar year 2007 resulting from diversions for Nevada above Hoover Dam are projected to be maf (366.3 mcm). The total inflow into Lake Mead is a combination of water released from Glen Canyon Dam plus inflows from the tributaries in the reach between Glen Canyon and Hoover Dams. In water year 2007, inflow into Lake Mead was maf (10,985 mcm). For water year 2008, under the most probable assumptions, total inflow into Lake Mead is anticipated to be maf (11,249 mcm). Under the most probable inflow conditions during water year 2008, Lake Mead will be at its maximum elevation of 1, feet (340.6 meters), with maf (16,159 mcm) in storage, at the end of February Lake Mead will likely decline during water year 2008 to reach its minimum elevation of approximately 1, feet (335.1 meters), with approximately maf (14,099 mcm) in storage, at the end of July Based on the August Month Study, Lake Mead s elevation on January 1, 2008, was projected to be 1, feet (339.8 meters). Therefore, in accordance with Section 2.B.5 of the Interim Guidelines, the ICS Surplus Condition will govern the releases from Lake Mead in calendar year Releases from Lake Mead through Hoover Dam for water year and calendar year 2008 are anticipated to be approximately the same as 2007 releases. In September 2005, Reclamation initiated a process in accordance with NEPA to develop additional operational guidelines for Lake Powell and Lake Mead in response to the AOP February 25, 2008

129 continued drought and increasing water demands on the system. A ROD adopting the Interim Guidelines was signed by the Secretary on December 13, The Interim Surplus Guidelines ROD included ESA conservation measures. One such conservation measure specified in Article X(4)(1) includes provisions for spawning razorback suckers in Lake Mead. Reclamation continues to provide funding and support for the ongoing Lake Mead Razorback Sucker study. The focus of the study has been on locating populations of razorbacks in Lake Mead, documenting use and availability of spawning areas at various water elevations, continuing aging studies, and confirming recruitment events. Based on the anticipated operation of Lake Powell for water year 2008, no changes in operations to provide rising elevations in Lake Mead are expected in the spring of Lakes Mohave and Havasu At the beginning of water year 2007, Lake Mohave was at an elevation of feet (194.7 meters), with an active storage of maf (1,954 mcm). The water level of Lake Mohave was regulated between elevation feet (193.3 meters) and feet (196.5 meters) throughout the water year, ending at an elevation of feet (194.2 meters) with maf (1,906 mcm) in storage. The total release from Lake Mohave through Davis Dam for water year 2007 was maf (11,401 mcm) for downstream water use requirements. The calendar year 2007 total release is projected to be maf (11,209 mcm). For water year and calendar year 2008, Davis Dam is expected to release approximately the same amount of water as in The water level in Lake Mohave will be regulated between an elevation of approximately 633 feet (193 meters) and 645 feet (197 meters). Lake Havasu started water year 2007 at an elevation of feet (136.1 meters) with maf (684.6 mcm) in storage. The water level of Lake Havasu was regulated between elevation feet (136.2 meters) and feet (136.7 meters), throughout the water year, ending at an elevation of feet (136.5 meters), with maf (710 mcm) in storage. During water year 2007, maf (8,395 mcm) were released from Parker Dam. The calendar year 2007 total release is projected to be maf (8,402 mcm). Diversions from Lake Havasu during calendar year 2007 by CAP and MWD are projected to be maf (1,935 mcm) and maf (860 mcm), respectively. For water year 2008, Parker Dam is expected to release approximately the same amount of water as in water year Diversions from Lake Havasu in calendar year 2008 by CAP and MWD are expected to be maf (1,943 mcm) and maf (967 mcm), respectively. Lakes Mohave and Havasu are scheduled to be drawn down in the late summer and fall months to provide storage space for local storm runoff and will be filled in the winter to meet higher summer water needs. This drawdown will also correspond with normal maintenance at both Davis and Parker powerplants which is scheduled for September through February AOP February 25, 2008

130 At Davis Dam, a major overhaul of Unit No. 2 is scheduled for October 1, 2007, through March 6, This overhaul will include removal and maintenance of the fixed wheel gate and hydraulic cylinder, as well as testing the generator windings. Rehabilitation of the fixed wheel gates of Units 5, 4, and 3, were completed in water years 2005, 2006, and 2007, respectively. Rehabilitation of the fixed wheel gate of Unit 1 is tentatively scheduled for water year At Parker Dam, the stainless steel turbine was replaced and the generator was re-wound on Unit 3 in calendar year A major turbine overhaul of Unit 1 is scheduled for September 7, 2007, through February 29, During 2008, Lake Mohave will continue to be operated under the constraints as described in the Interim Surplus Guidelines Biological Opinion on Lower Colorado River Operations and Maintenance, as extended through the LCR MSCP Biological and Conference Opinion. Reclamation, as provided in the LCR MSCP ROD, will continue these existing operations in Lake Mohave that benefit native fish and will explore additional ways to provide benefits to native fish. The normal filling and drawdown pattern of Lake Mohave coincides well with the fishery spawning period. Since lake elevations for Lake Mohave and Lake Havasu will be typical of previous years, normal conditions are expected for boating and other recreational uses. Reclamation is the lead agency in the Native Fish Work Group, a multi-agency group of scientists attempting to augment the aging stock of the endangered razorback sucker in Lake Mohave. Larval razorback suckers are captured by hand in and around spawning areas in late winter and early spring for rearing at Willow Beach National Fish Hatchery below Hoover Dam. The following year, 1-year old razorback suckers are placed into predatorfree, lake-side backwaters for rearing through the spring and summer. When Lake Mohave is normally drawn down during August through October, these fish are harvested from these rearing areas and then released into Lake Mohave. The razorback suckers grow very quickly, usually exceeding 10 inches (254 mm) in length by September. Between February and April 2007, some 20,568 wild razorback sucker larvae were captured from spawning congregations on Lake Mohave and delivered to Willow Beach National Fish Hatchery for initial rearing. Approximately 1,000 subadult razorback suckers were stocked into lake-side ponds during March These latter fish were harvested in the fall of Bill Williams River Tributary inflows were below average for water year Abnormally dry to extreme drought conditions persisted for water year 2007 throughout western Arizona, including the Bill Williams River watershed. Tributary inflow from the Bill Williams River into the mainstream of the Colorado River totaled maf (30.84 mcm) for water year 2007, approximately 25 percent of the long-term average. Releases in water year 2007 from the United States Army Corp of Engineers (USACE s) Alamo Dam were coordinated with the Service and the Bill Williams Steering Committee to maintain riparian habitat established in water year 2005 and Alamo Lake elevation AOP February 25, 2008

131 was approximately 1,119.8 feet (341.3 meters) after October 1, A storage volume of maf (2.47 mcm), equivalent to the storage between approximately elevations 1,116.0 feet (340.2 meters) and 1,115.4 feet (340.0 meters), was released from April 9, 2007, to April 10, The purpose of the release was to maintain downstream riparian habitat. The April 9-10, 2007, release from Alamo Dam increased from approximately 40 cfs (1 cms) to approximately 1,000 cfs (30 cms) for an 18-hour period, tapering to approximately 40 cfs (1 cms) over the following day. Data collection associated with Alamo Dam releases supports ongoing studies conducted by the Bill Williams Steering Committee. The Bill Williams Steering Committee is chaired by the Service and is comprised of other stakeholders, including, but not limited to, Reclamation, the USACE, the Bureau of Land Management, and other governmental and non-governmental organizations. Senator Wash and Laguna Reservoirs Operations at Senator Wash Reservoir allow regulation of water deliveries to United States water users upstream and downstream of Imperial Dam and Mexican water users downstream of Imperial Dam. The reservoir is utilized as an off-stream storage facility to meet downstream water demands and to conserve water for future uses in the United States and the scheduled uses of Mexico in accordance with the 1944 United States-Mexico Water Treaty obligations. Senator Wash Reservoir is the only major storage facility below Parker Dam (approximately 142 river miles downstream) and has a storage capacity of maf (17.27 mcm) at full pool elevation of feet (76.5 meters). Operational objectives are to store excess flows from the river caused by water user cutbacks and side wash inflows due to rain. Stored waters are utilized to meet the United States and Mexico s demands. Since 1992 elevation restrictions have been placed on Senator Wash Reservoir due to potential piping and liquefaction of foundation and embankment materials at West Squaw Lake Dike and Senator Wash Dam. Currently, Senator Wash is restricted to an elevation of feet (73.2 meters) with maf (11.10 mcm) of storage, a loss of about maf (6.167 mcm) of storage from its original capacity. Senator Wash Reservoir elevation must not exceed elevation feet (73.2 meters) for more than 10 consecutive days. This reservoir restriction is expected to continue in Laguna Reservoir is a regulating storage facility located approximately five river miles downstream of Imperial Dam. Operational objectives are similar to those for Senator Wash Reservoir and the reservoir is primarily used to capture sluicing flows from Imperial Dam. The storage capability of Laguna Reservoir has diminished from about 1,500 acre-feet (1.850 mcm) to approximately 400 acre-feet (0.493 mcm) due to sediment accumulation and vegetation growth. Sediment accumulation in the reservoir has occurred primarily due to flood releases that occurred in 1983 and 1984, and flood control or space building releases that occurred between 1985 and 1988 and from 1997 through Action to restore the lost capacity to 1,500 acre-feet at the Laguna Reservoir is ongoing. It is anticipated that dredging to restore its capacity will begin in early 2008, and be completed within a 3 year period, subject to the availability of funds AOP February 25, 2008

132 Imperial Dam Imperial Dam is the last diversion dam on the Colorado River for United States water users. From the head works at Imperial Dam, the diversions of flows for the United States and Mexico s water users occur into the All-American Canal on the California side, and into the Gila Gravity Main Canal on the Arizona side of the dam. These diversions supply all the irrigation districts in the Yuma area, in Wellton-Mohawk, in the Imperial and Coachella Valleys, and through Siphon Drop and Pilot Knob to the Northerly International Boundary (NIB) for diversion at Morelos Dam to the Mexicali Valley in Mexico. The diversions also supply much of the domestic and industrial water needs in the Yuma area. Flows arriving at Imperial Dam for calendar year 2007 were expected to be maf (8,402 mcm). The flows arriving at Imperial Dam for calendar year 2008 were anticipated to be approximately the same as calendar year Gila River Flows Drought conditions persisted for water 2007 throughout the Lower Division States and the southwestern United States. Abnormally dry to extreme drought conditions persisted throughout Arizona, contributing to 79 percent of average precipitation being recorded in the Gila River Basin. During water year 2007, no tributary inflow from the Gila River reached the mainstream of the Colorado River. Additional Regulatory Storage In 2004 Reclamation completed a study that evaluated the needs and developed options for additional water storage facilities on the mainstream of the Colorado River below Parker Dam. The study, developed in cooperation with IID, Coachella Valley Water District (CVWD), San Diego County Water Authority (SDCWA), and MWD, recommended the construction of additional storage north of the Drop 2 portion of the All-American Canal. The Drop 2 Storage Reservoir is in the final engineering design phase. The purpose of the planned maf (9.875 mcm) reservoir is the same as Senator Wash and it will be operated similar to Senator Wash to capture extra water in the system, especially during storm events. The reservoir will make up for the loss of water storage at Senator Wash because of the operational restrictions and allow for additional regulatory storage. Additional storage will allow for more efficient management of water below Parker Dam. Construction of the first phase of the Drop 2 Storage Reservoir is scheduled to start in calendar year 2008, pursuant to federal law, with a tentative completion date in calendar year Two agreements 19 were executed concurrent with the Interim Guidelines ROD that fund the construction of the Drop 2 Storage Reservoir and the integral confluence structure and provide for the funding parties to receive quantities of System Efficiency ICS in consideration for their financial contributions. 19 Funding and Construction of the Lower Colorado River Drop 2 Storage Reservoir Project Agreement among the United States, SNWA, and the CRCN; Advance Funding and Construction of a Confluence Structure as an Integral Component of the Lower Colorado River Drop 2 Storage Reservoir Project Agreement among the United States of America, SNWA and the Imperial Irrigation District (IID) AOP February 25, 2008

133 Yuma Desalting Plant In calendar year 2007 the amount of water discharged through the Main Outlet Drain (bypass flows) was anticipated to be maf (135.7 mcm) at an approximate concentration of total dissolved solids of 2,430 parts per million (ppm). Water users in the Colorado River Basin have raised concerns over the continued bypass of Wellton-Mohawk agricultural return flow around Morelos Dam to the Cienega de Santa Clara, a wetland of approximately 40,000 acres (16,200 hectares) of open water and vegetation that is within a Biosphere Reserve in Mexico. These flows do not count as part of Mexico s maf (1,850 mcm) allotment under the 1944 United States-Mexico Water Treaty. On October 26, 2005, Reclamation submitted to Congress a report that describes activities required to operate the Yuma Desalting Plant (YDP), provides an estimate of how long those activities would take, and presents a current estimate of their anticipated cost. In addition, this report explores interim and/or supplemental opportunities for replacement of water that is bypassed into Mexico, including options that do not potentially have an adverse impact on the Cienega de Santa Clara. Reclamation initiated the Bypass Flow Public Consultation Process on September 22, 2005, to investigate options to replace or recover the bypass flows. One option included an operational demonstration of YDP in conjunction with the System Conservation (SC) Demonstration Program. Reclamation anticipates the Bypass Flow Public Consultation Process will conclude in From March 1, 2007, to May 31, 2007, the YDP concluded a three-month operating run. The demonstration operation of the plant was the culmination of one year of preparation. The demonstration was designed to meet five objectives: 1) demonstrate the operability of the plant, 2) demonstrate the plant s use of current technologies, 3) validate cost and performance estimates for the plant, 4) improve overall plant readiness, and 5) provide measurements of water quality impacts to the Cienega de Santa Clara. All five objectives were successfully achieved. By the conclusion of the three-month run, 4,349 acre-feet (5.364 mcm) had been delivered to the Colorado River and included in water deliveries to Mexico, preserving an equivalent volume in Colorado River system storage. The plant produced 2,632 acre-feet (3.247 mcm) of product water which was blended with 1,717 acre-feet (2.118 mcm) of untreated bypass flow prior to discharge into the Colorado River. Intentionally Created Surplus The Interim Guidelines ROD included the adoption of the ICS mechanism that among other things encourages the efficient use and management of Colorado River water in the Lower Basin. ICS may be created through several types of projects that create water system efficiency or extraordinary conservation or tributary conservation or the importation of non- Colorado River System water into the Colorado River mainstream. The creation and delivery of ICS during the term of the Interim Guidelines is conditioned upon several AOP February 25, 2008

134 implementing agreements 20 that were executed concurrent with the Interim Guidelines ROD. ICS may be created and delivered in 2008 in compliance with the Interim Guidelines and appropriate delivery and forbearance agreements. Subject to the appropriate approvals and implementing agreements, SNWA is contemplating the creation and delivery of Tributary Conservation ICS from the Muddy and Virgin Rivers project and MWD is contemplating the creation and delivery of System Efficiency ICS from the Drop 2 Reservoir Storage project. MWD is also contemplating creation and/or delivery of Extraordinary Conservation ICS depending upon water supply and demand conditions in MWD s service area. Intentionally Created Surplus Water Demonstration Program In 2006 Reclamation implemented a demonstration program in the Lower Basin to create Intentionally Created Surplus Water (ICS Demonstration Program). The ICS Demonstration Program allowed entitlement holders to undertake extraordinary conservation activities in 2006 and 2007 to reduce their approved annual consumptive use of Colorado River water and account for that conserved water in Lake Mead. 21 The ICS created and accounted for under the ICS Demonstration Program is now available for delivery pursuant to the Interim Guidelines and implementing agreements. Reclamation entered into an agreement with MWD for the creation of Intentionally Created Surplus Water in calendar year Although MWD may, either separately or in conjunction with other California agencies with rights to use Colorado River water, create up to maf (246.7 mcm) in calendar year 2007, MWD does not anticipate the creation of ICS water in calendar year In 2008, MWD may take delivery of up to maf (56.74 mcm) of Intentionally Created Surplus Water created under the ICS Demonstration Program. Reclamation also entered into an agreement with IID for the creation of Intentionally Created Surplus Water in Although IID may undertake extraordinary conservation measures to create up to maf (30.84 mcm) in calendar year 2007, IID does not anticipate the creation of Intentionally Created Surplus Water in calendar year System Conservation of Colorado River Water Demonstration Program In 2006 Reclamation implemented the System Conservation of Colorado River Water Demonstration Program (SC Demonstration Program) in the Lower Basin which allows 20 Delivery Agreement between the United States and IID; Delivery Agreement between the United States and MWD; Delivery Agreement between the United States, SNWA and the CRCN; Lower Colorado River Basin Intentionally Created Surplus Forbearance Agreement among the Arizona Department of Water Resources, SNWA, CRCN, the Palo Verde Irrigation District (PVID), IID, CVWD, MWD, and the City of Needles; and the California Agreement for the Creation and Delivery of Extraordinary Conservation Intentionally Created Surplus among the PVID, IID, CVWD, MWD and the City of Needles 21 No ICS Water is projected to be conserved in calendar year 2007 by MWD and IID. 22 Agreement between Reclamation and MWD to Implement a Demonstration Program to Create Intentionally Created Surplus Water, May 18, Agreement between Reclamation and IID to Implement a Demonstration Program to Create Intentionally Created Surplus Water, June 26, AOP February 25, 2008

135 entitlement holders to participate in voluntary conservation to conserve a portion of their approved annual consumptive use of Colorado River water in exchange for appropriate compensation provided by Reclamation. 24 The water conserved (SC Water) is retained in Lake Mead to assist in providing an interim, supplemental source of water to replace the drainage water from the Wellton-Mohawk Irrigation and Drainage District that is bypassed to the Cienega de Santa Clara and the reject stream from operation of the Yuma Desalting Plant. Reclamation entered into an agreement with MWD for the creation of SC Water in Through this program, MWD has undertaken extraordinary measures to conserve maf (8.634 mcm) of SC Water in calendar year This water is retained in Lake Mead. Delivery of Water to Mexico Total delivery to Mexico for calendar year 2007 was projected to be approximately maf (1,871 mcm), with excess flow of approximately maf (20.97 mcm). Of the total delivery, approximately maf (172.8 mcm) is projected to be delivered at the Southerly International Boundary (SIB) and maf (1,699 mcm) was projected to be delivered at the NIB. The excess flows in 2007 resulted from a combination of rejected water from water users after rain storms, side-wash inflow into the Colorado River, and spills from irrigation facilities below Imperial Dam to the river. As part of Mexico s delivery schedule, it is anticipated that 602 acre-feet (0.743 mcm) will be diverted from Lake Havasu and delivered through MWD, San Diego County Water Authority, and the Otay Water District s respective distribution system facilities to Tijuana, Baja California at the request of the Mexican section of the IBWC in calendar year In 2008, it is anticipated that maf (172.7 mcm) will be delivered to Mexico at the SIB. In accordance with Minute No. 310 and the Emergency Delivery Agreement 26 up to maf per month (1.233 mcm) may be delivered for Tijuana through MWD, San Diego County Water Authority, and the Otay Water District s respective distribution system facilities in California. The remainder of Mexico s available water will be delivered at NIB. To further improve control of the deliveries of water from Parker Dam, Senator Wash Reservoir and the reservoirs behind Imperial Dam and Laguna Dam will continue to be operated at lower elevations during periods of potential rain storms to capture flows in excess of water demand at Imperial Dam. As mentioned previously, the Drop 2 Storage Reservoir will improve control of water deliveries below Parker Dam once construction is complete. Drainage flows to the Colorado River from the Yuma Mesa Conduit and South Gila Conduit were projected to be maf (55.5 mcm) and maf (80.18 mcm), respectively, for calendar year As stated in Minute 242, the maximum allowable salinity differential is 24 In calendar year 2007, it was assumed that 7,000 acre-feet of SC Water would be conserved. 25 Agreement between Reclamation and MWD to Implement a Demonstration Program for System Conservation of Colorado River Water, August 15, The Agreement for Temporary Emergency Delivery of a Portion of the Mexican Treaty Waters of the Colorado River to the International Boundary in the Vicinity of Tijuana, Baja California, Mexico, and for Operation of the Facilities in the United States, applicable through November 9, AOP February 25, 2008

136 145 ppm by the United States measurement or count and 151 ppm by the Mexican count. The salinity differential for calendar year 2007 is projected to be 143 ppm by the United States count. Mexico has identified four critical months, October through January, regarding improving the quality of water delivered at the SIB. As a matter of comity, the United States has agreed to reduce the salinity of water delivered at SIB during this period. To accomplish the reduction in salinity, the United States constructed a diversion channel to bypass up to maf (9.868 mcm) of Yuma Valley drainage water during the four critical months identified by Mexico. This water will be replaced by better quality water from the Minute 242 well field to reduce the salinity at SIB. Facilities required for real-time monitoring and control of the flow and salinity of water delivered to SIB will be operational in calendar year No water is projected to be bypassed in 2007, however, up to maf (9.868 mcm) could be spilled to the diversion channel for salinity control in AOP February 25, 2008

137 2008 DETERMINATIONS The AOP provides guidance regarding reservoir storage and release conditions during the upcoming year, based upon congressionally mandated and authorized storage, release, and delivery criteria and determinations. After meeting these requirements, specific reservoir releases may be modified within these requirements as forecasted inflows change in response to climatic variability and to provide additional benefits coincident to the projects multiple purposes. Upper Basin Reservoirs Releases from Lake Powell during water year 2008 shall be made consistent with Section 6 of the Interim Guidelines. Under the most probable and minimum probable inflow scenario, releases from Lake Powell will be made consistent with Section 6.B.1 of the Interim Guidelines, with a water year release of 8.23 maf (10,150 mcm). Under the maximum probable inflow scenario, Section 6.A, the Equalization Tier, of the Interim Guidelines would control the release of water from Lake Powell in water year Pursuant to Section 602(b) of the Colorado River Basin Project Act and Section 1804(c)(3) of the Grand Canyon Protection Act, the Secretary is required to develop this AOP in consultation with the Upper Colorado River Commission, representatives from the three Lower Division States, and with the general public. Section 602(a) of the Colorado River Basin Project Act provides for the storage of Colorado River water in Upper Basin reservoirs and the release of water from Lake Powell that the Secretary finds reasonably necessary to assure deliveries to comply with Articles III(c), III(d), and III(e) of the 1922 Colorado River Compact without impairment to the annual consumptive use in the Upper Basin. The Operating Criteria provide that the annual plan of operation shall include a determination of the quantity of water considered necessary to be in Upper Basin storage at the end of the water year after taking into consideration all relevant factors including historic stream flows, the most critical period of record, the probabilities of water supply, and estimated future depletions. Water not required to be so stored will be released from Lake Powell: to the extent it can be reasonably applied in the States of the Lower Division to the uses specified in Article III(e) of the 1922 Colorado River Compact, but these releases will not be made when the active storage in Lake Powell is less than the active storage in Lake Mead; to maintain, as nearly as practicable, active storage in Lake Mead equal to the active storage in Lake Powell; and to avoid anticipated spills from Lake Powell. Taking into consideration all relevant factors required by Section 602(a)(3) of the Colorado River Basin Project Act and the Operating Criteria, it is determined that the active storage in Upper Basin reservoirs forecast for September 30, 2008, under the most probable inflow scenario would not exceed the storage required under Section 602(a) of the Colorado River AOP February 25, 2008

138 Basin Project Act. Consistent with Section 6.B.3 of the Interim Guidelines, if the April Month Study projects the September 30, 2008, Lake Powell elevation to be greater than elevation 3,636 feet, the Equalization Tier, Section 6.A of the Interim Guidelines will govern the release of water from Lake Powell for the remainder of water year 2008 (through September 2008). Lower Basin Reservoirs Pursuant to Article III of the Operating Criteria and consistent with the Consolidated Decree, water shall be released or pumped from Lake Mead to meet the following requirements: (a) 1944 United States-Mexico Water Treaty obligations; (b) Reasonable beneficial consumptive use requirements of mainstream users in the Lower Division States; (c) Net river losses; (d) Net reservoir losses; (e) Regulatory wastes; and (f) Flood control. The Operating Criteria provide that after the commencement of delivery of mainstream water by means of the CAP, the Secretary will determine the extent to which the reasonable beneficial consumptive use requirements of mainstream users are met in the Lower Division States. Reasonable beneficial consumptive use requirements are met depending on whether a Normal, Surplus, or Shortage Condition has been determined. The Normal Condition is defined as annual pumping and release from Lake Mead sufficient to satisfy maf (9,251 mcm) of consumptive use in accordance with Article III(3)(a) of the Operating Criteria and Article II(B)(1) of the Consolidated Decree. The Surplus Condition is defined as annual pumping and release from Lake Mead sufficient to satisfy in excess of maf (9,251 mcm) of consumptive use in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. An ICS Surplus Condition is defined as a year in which Lake Mead s elevation is projected to be above elevation 1,075 feet on January 1, a Flood Control Surplus has not been determined, and delivery of ICS has been requested. The Secretary may determine an ICS Surplus Condition in lieu of a Normal Condition or in addition to other operating conditions that are based solely on the elevation of Lake Mead. The Shortage Condition is defined as annual pumping and release from Lake Mead insufficient to satisfy maf (9,251 mcm) of consumptive use in accordance with Article III(3)(c) of the Operating Criteria and Article II(B)(3) of the Consolidated Decree. The Interim Guidelines, which became effective December 13, 2007, and are being utilized in calendar year 2008, serve to implement the narrative provisions of Article III(3)(a), Article III(3)(b), and Article III(3)(c) of the Operating Criteria and Article II(B)(1), Article II(B)(2), and Article II(B)(3) of the Consolidated Decree for the period through These specific interim guidelines will be used annually by the Secretary to determine the quantity of water available for use within the Lower Division States. Consistent with the Interim Guidelines, the August Month Study was used to forecast the system storage as of January 1, Based on this projected elevation of Lake AOP February 25, 2008

139 Mead and consistent with Section 2.B.5 of the Interim Guidelines, the ICS Surplus Condition will govern releases for use in the states of Arizona, Nevada, and California during calendar year 2008 in accordance with Article III(3)(b) of the Operating Criteria and Article II(B)(2) of the Consolidated Decree. Article II(B)(6) of the Consolidated Decree allows the Secretary to allocate water that is apportioned to one Lower Division State but is for any reason unused in that state to another Lower Division State. This determination is made for one year only, and no rights to recurrent use of the water accrue to the state that receives the allocated water. No unused apportionment for calendar year 2008 is anticipated. If any unused apportionment becomes available after adoption of this AOP, Reclamation, on behalf of the Secretary, shall allocate any such available unused apportionment for calendar year 2008 in accordance with Article II(B)(6) of the Consolidated Decree. Water may be made available for diversion pursuant to 43 CFR Part 414 to contractors within the Lower Division States. The Secretary shall make Intentionally Created Unused Apportionment (ICUA) available to contractors in Arizona, California, or Nevada for the off-stream storage or consumptive use of water pursuant to individual SIRA agreements and 43 CFR Part 414. In calendar year 2007, approximately maf (20.97 mcm) of ICUA water stored in Arizona was projected to be recovered for use in California by MWD. In calendar year 2008, maf (30.84 mcm) of ICUA water stored in Arizona is projected to be recovered for use in California by MWD. SNWA may propose to make from to maf (18.5 to 30.8 mcm) of unused Nevada basic apportionment available for storage by MWD in On October 10, 2003, the Secretary approved the ROD for the Inadvertent Overrun and Payback Policy (IOPP) which became effective January 1, The IOPP is in effect during calendar year 2008 with calendar year 2006 paybacks to begin in calendar year The Colorado River Water Delivery Agreement also requires payback of California overruns occurring in 2001 and 2002 as noted in Exhibit C of that document. Each district with a payback obligation under Exhibit C may at its own discretion elect to accelerate paybacks. It is anticipated that California paybacks for calendar years 2007 and 2008 will total maf (49.34 mcm) and maf (16.04 mcm), respectively. In calendar years 2007 and 2008, paybacks occurring in California result from Exhibit C obligations and IOPP overruns. In calendar years 2007 and 2008, paybacks for Arizona result only from IOPP overruns. During calendar year 2007, the scheduled Arizona paybacks were expected to total 606 ac-ft (0.75 mcm). In calendar year 2008, Arizona paybacks are projected to total 3,570 ac-ft (4.40 mcm). Given the limitation of available supply and the low inflow amounts within the Colorado River Basin, the Secretary, through Reclamation, will continue to review Lower Basin operations to assure that all deliveries and diversions of mainstream water are in strict accordance with the Consolidated Decree, applicable statutes, contracts, rules, and agreements AOP February 25, 2008

140 As provided in Section 7.C of the Interim Guidelines, the Secretary may undertake a midyear review to consider revisions of the current AOP. For Lake Mead, the Secretary shall revise the determination in any mid-year review for the current year only to allow for additional deliveries from Lake Mead pursuant to Section 2 of the Interim Guidelines United States-Mexico Water Treaty Under the most probable, probable minimum, and probable maximum inflow scenarios, water in excess of that required to supply uses in the United States will not be available. Vacant storage space in mainstream reservoirs is substantially greater than that required by flood control regulations. Therefore, a volume of maf (1,850 mcm) of water will be available to be scheduled for delivery to Mexico during calendar year 2008 in accordance with Article 15 of the 1944 United States-Mexico Water Treaty and Minutes 242 and 310 of the IBWC. Calendar year schedules of the monthly deliveries of Colorado River water are formulated by the Mexican Section of the IBWC and presented to the United States Section before the beginning of each calendar year. Pursuant to the 1944 United States-Mexico Water Treaty, the monthly quantity prescribed by those schedules may be increased or decreased by not more than 20 percent of the monthly quantity, upon 30 days notice in advance to the United States Section. Any change in a monthly quantity is offset in another month so that the total delivery for the calendar year is unchanged AOP February 25, 2008

141 DISCLAIMER Nothing in this AOP is intended to interpret the provisions of the Colorado River Compact (45 Stat. 1057); the Upper Colorado River Basin Compact (63 Stat. 31); the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, Treaty Between the United States of America and Mexico (Treaty Series 994, 59 Stat. 1219); the United States/Mexico agreement in Minute No. 242 of August 30, 1973, (Treaty Series 7708; 24 UST 1968); the Consolidated Decree entered by the Supreme Court of the United States in Arizona v. California (547 U.S 150 (2006)); the Boulder Canyon Project Act (45 Stat. 1057); the Boulder Canyon Project Adjustment Act (54 Stat. 774; 43 U.S.C. 618a); the Colorado River Storage Project Act (70 Stat. 105; 43 U.S.C. 620); the Colorado River Basin Project Act (82 Stat. 885; 43 U.S.C. 1501); the Colorado River Basin Salinity Control Act (88 Stat. 266; 43 U.S.C. 1951); the Hoover Power Plant Act of 1984 (98 Stat. 1333); the Colorado River Floodway Protection Act (100 Stat. 1129; 43 U.S.C. 1600); or the Grand Canyon Protection Act of 1992 (Title XVIII of Public Law , 106 Stat. 4669) AOP February 25, 2008

142 ATTACHMENT I Monthly inflow, monthly release, and end of month contents for Colorado River reservoirs (October 2006 through December 2008) under the probable maximum, most probable, and probable minimum inflow scenarios, and historic end of month contents AOP February 25, 2008

143 Dec-08 Oct-08 Aug-08 Jun Fontenelle Monthly Inflow Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

144 Dec-08 Oct-08 Aug-08 Jun Fontenelle Monthly Releases Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

145 Dec-08 Oct-08 Aug-08 Jun Fontenelle Monthly Storage Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

146 Dec-08 Oct-08 Aug-08 Jun Flaming Gorge Monthly Inflow Probable Minimum Most Probable Probable Maximum Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Dec-06 Oct AF

147 Dec-08 Oct-08 Aug-08 Jun Flaming Gorge Monthly Releases Probable Minimum Most Probable Probable Maximum Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Dec-06 Oct AF

148 Dec-08 Oct-08 Aug-08 Jun Flaming Gorge Monthly Storage Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

149 Dec-08 Oct-08 Aug-08 Jun Blue Mesa Monthly Inflow Probable Minimum Most Probable Probable Maximum Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Dec-06 Oct AF

150 Dec-08 Oct-08 Aug-08 Jun Blue Mesa Monthly Storage Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

151 Dec-08 Oct-08 Aug-08 Jun Crystal Monthly Releases Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

152 Dec-08 Oct-08 Aug-08 Jun Navajo Monthly Inflow Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

153 Dec-08 Oct-08 Aug-08 Jun Navajo Monthly Releases Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

154 Dec-08 Oct-08 Aug-08 Jun Navajo Monthly Storage Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

155 Dec-08 Oct-08 Aug-08 Jun Lake Powell Monthly Inflow Probable Minimum Most Probable Probable Maximum Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Dec-06 Oct AF

156 Dec-08 Oct-08 Aug-08 Jun Lake Powell Monthly Releases Probable Minimum Most Probable Probable Maximum Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Dec-06 Oct AF

157 Dec-08 Oct-08 Aug-08 Jun Lake Powell Monthly Storage Most Probable Probable Maximum Probable Minimum Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Apr-07 Feb-07 Dec-06 Oct AF

158 Oct-08 Dec-08 Aug-08 Jun-08 Apr Lake Mead Monthly Inflow Aug-07 Oct-07 Dec-07 Feb-08 Probable Minimum Most Probable Probable Maximum WY WY 2008 Feb-07 Apr-07 Jun-07 Dec-06 Oct AF

159 Oct-08 Dec-08 Aug-08 Jun Lake Mead Monthly Releases Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

160 Oct-08 Dec-08 Aug-08 Jun-08 17,000 16,000 15,000 14,000 13,000 12,000 11,000 10,000 Lake Mead Monthly Storage Probable Minimum Most Probable Probable Maximum Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 WY WY 2008 Feb-07 Dec-06 Oct AF

161 Fontenelle AF Monthly Storage Jan Sep 2007

162 Flaming Gorge AF Monthly Storage Jan Sep 2007

163 Blue Mesa AF Monthly Storage Jan Sep 2007

164 Navajo AF Monthly Storage Jan Sep 2007

165 Lake Powell AF Monthly Storage Jan Sep 2007

166 Lake Mead AF Monthly Storage Jan Sep 2007

167