American River Group Thursday, October 18th, :30 PM Central Valley Operation Office, Room El Camino Ave. Sacramento, CA 95821

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1. Participant Introductions (1:30-1:40) American River Group Thursday, October 18th, 2018 1:30 PM Central Valley Operation Office, Room 302 3310 El Camino Ave. Sacramento, CA 95821 2. Annual Report Update (1:40-1:50) 3. Fisheries Updates (1:50-2:05) 3. Operations Forecast (2:05-2:20) 4. Temperature Management (2:20-2:35) 5. Discussion (2:35-3:00) a. Power Bypass 6. Schedule Next Meeting The next meeting is scheduled to take place on Thursday, November 15th, 2018 7. Adjourn

SMUD Upper American River Project Update Conditions 18 October 2018: October precipitation through 10/18/2018 7:00:00 AM is.99 in., which is 30% of the October average of 3.30. Precip for the water year to date is.99 which is 52% of average to date (1.92 ) and 2% of the entire water year average of 57.32. Reservoir storage for Loon Lake, Union Valley and Ice House Reservoirs is currently at 63% capacity (231,862 acre feet). Last year today, storage was at 67% (253,576 acre feet). Total capacity of the three reservoirs is 379,174 acre feet. The SMUD reservoirs are at 99% of historical average at this date (18 October historical average 235,303 acre feet / 64% capacity). The reservoirs have decreased in volume by 1% since last week. During the month of September 2018 SMUD released from the Upper American River Project reservoirs approximately 48,046 acre feet of water, with average flows at 807 cfs below Chili Bar. So far in October (October 1-17), we have released 17,675 AF, at flows of ~524 cfs below Chili Bar on average. Runoff into the storage reservoir basins is 91% of median to date through Oct 17. The snowpack is 0% of average at selected snow sensors. Cloud seeding will resume November 15. Maintenance at various units is taking place.

American River Summary Conditions October (On-going): No unusual conditions or occurances to report. Storage/Release Management Conditions Releases to meet Delta needs over summer. Temperature Management: Cooler temperatures are helping keep us well under the temperature objective right now. Higher than expected inflows are helping to keep storage up, and cold water pool volume is slightly higher than originally expected.

OCTOBER 17, 2018 RESERVOIR TRINITY UNITED STATES DEPARTMENT OF THE INTERIOR U.S. BUREAU OF RECLAMATION-CENTRAL VALLEY PROJECT-CALIFORNIA DAILY CVP WATER SUPPLY REPORT RESERVOIR RELEASES IN CUBIC FEET/SECOND DAM LEWISTON WY 2018 WY 2019 302 RUN DATE: 300 October 18, 2018 15 YR MEDIAN 303 SACRAMENTO KESWICK 7,396 7,820 6,506 FEATHER OROVILLE (SWP) 2,400 2,450 2,400 AMERICAN NIMBUS 2,048 1,658 1,540 STANISLAUS GOODWIN 703 1,253 703 SAN JOAQUIN FRIANT 350 575 349 STORAGE IN MAJOR RESERVOIRS IN THOUSANDS OF ACRE-FEET RESERVOIR CAPACITY 15 YR AVG WY 2018 WY 2019 % OF 15 YR AVG TRINITY 2,448 1,361 1,763 1,479 109 SHASTA 4,552 2,321 3,265 2,281 98 FOLSOM 977 420 599 433 103 NEW MELONES 2,420 1,310 2,018 1,777 136 FED. SAN LUIS 966 317 721 411 130 TOTAL NORTH CVP 11,363 5,729 8,366 6,381 111 MILLERTON 520 248 357 278 112 OROVILLE (SWP) 3,538 1,694 1,261 1,265 75 ACCUMULATED INFLOW FOR WATER YEAR TO DATE IN THOUSANDS OF ACRE-FEET RESERVOIR CURRENT WY 2019 WY 1977 WY 1983 15 YR AVG % OF15 YR AVG TRINITY 3 4 5 5 53 SHASTA 101 124 132 110 91 FOLSOM 30 37 59 35 88 NEW MELONES 21 ---- 28 25 85 MILLERTON 37 19 94 33 114 ACCUMULATED PRECIPITATION FOR WATER YEAR TO DATE IN INCHES RESERVOIR TRINITY AT FISH HATCHERY SACRAMENTO AT SHASTA DAM AMERICAN AT BLUE CANYON STANISLAUS AT NEW MELONES SAN JOAQUIN AT HUNTINGTON LK CURRENT WY 2019 WY 1977 WY 1983 0.63 0.20 1.48 0.55 0.91 0.13 0.07 0.87 ---- 1.20 0.39 0.24 0.73 0.30 AVG (N YRS) 0.69 ( 56) 1.10 ( 61) 1.36 ( 43) 0.55 ( 40) % OF AVG 0.00 0.00 0.00 0.00 0.00 0.93 98 0.00 ( 43) 92 18 109 101 LAST 24 HRS

D A T E Mean Daily Temperatures ( F) Water NFA ARP AFD 1 AHZ AWP AWB Air CSU Release (CFS) Nimbus Storage (TAF) Folsom Unit Shuter Position / Load Percentage Aug 61.8 65.0 62.0 63.0 65.3 65.9 72.8 3280 09/01 62.6 59.1 60.4 62.5 65.4 66.6 72.2 1851 505 M 55 M 26 T 18 09/02 63.0 58.1 59.8 62.4 65.3 66.4 75.1 1850 505 M 30 M 70 T 1 09/03 63.3 57.7 60.0 61.7 64.7 65.9 71.3 1850 504 M 74 M 25 T 1 09/04 63.6 58.1 60.1 61.6 64.3 65.4 71.3 1850 503 M 29 M 69 T 1 09/05 63.2 58.9 60.4 61.9 64.7 65.6 70.8 1852 502 M 74 M 25 T 1 09/06 65.4 59.6 60.6 61.8 64.3 65.2 69.5 1839 500 M 72 M 28 T 1 09/07 67.5 58.5 60.7 62.2 65.0 66.0 74.9 1535 499 M 35 M 65 T 1 09/08 68.9 57.8 60.8 62.0 64.8 65.9 75.3 1826 497 M 72 M 27 T 1 09/09 66.1 58.8 61.0 62.2 64.7 65.7 74.3 1825 496 M 24 M 75 T 1 09/10 63.8 58.3 61.2 62.4 65.1 66.0 74.4 1825 494 M 23 M 76 T 0 09/11 63.6 58.3 61.2 62.3 64.8 65.7 71.8 1829 493 B 67 M 32 T 0 09/12 61.7 57.6 60.2 62.2 63.8 64.2 65.1 1826 492 B 18 M 82 T 0 09/13 61.0 59.0 61.0 61.9 64.3 64.6 67.2 1825 490 B 10 M 89 T 0 09/14 61.0 57.7 60.8 61.8 64.0 64.4? 66.5 1824 489 B 14 M 85 T 0 09/15 60.9 57.1 60.7 61.7 63.9 64.5 65.4 1777 489 B 18 M 82 T 0 09/16 60.2 57.1 61.3 61.7 63.8 64.1 63.6 1777 488 B 12 M 88 T 0 09/17 60.6 57.1 61.3 61.7 63.9 64.4 65.7 1776 487 B 11 M 88 T 0 09/18 61.1 57.0 61.5 61.9 64.0 64.5 65.5 1775 486 B 12 M 87 T 0 09/19 61.8 56.9 61.2 62.2 64.4 64.9 68.2 1778 485 B 14 M 86 T 0 09/20 62.2 58.2 61.2 62.4 64.7 65.2 70.2 1844 483 B 16 M 83 T 0 09/21 62.7 58.1 60.6 62.2 64.6 65.2 72.9 1775 482 B 24 M 76 T 0 09/22 63.0 56.1 60.4 62.2 64.4 65.1? 71.6 1775 481 B 28 M 72 T 0 09/23 63.1 56.4 60.8 62.0 64.4 65.0 71.9 1777 479 B 26 M 74 T 0 09/24 62.8 56.8 61.4 62.1 64.3 64.9 70.5 1774 477 B 18 M 82 T 0 09/25 62.8 56.6 61.6 62.0 64.4 65.0 71.8 1848 476 B 17 M 83 T 0 09/26 63.0 58.8 61.8 62.2 64.4 64.9 73.1 1834 473 B 14 M 86 T 0 09/27 63.4 58.9 61.8 62.2 64.5 65.2 73.7 1785 471 B 14 M 85 B 1 09/28 63.5 58.5 62.0 62.0 64.2 64.7 65.3 1768 470 B 14 M 86 B 1 09/29 63.1 58.1 61.8 62.2 64.1 64.1 64.3 1801 468 B 17 M 83 B 1 09/30 63.0 58.0 61.6 62.9 64.9 65.3 68.3 1781 467 B 12 M 80 B 8 - Sep 63.1 57.9 61.0 62.1 64.5 65.2 70.0 1802 Total AF 107210 Legend Notes Unit 1 Unit 2 Unit 3 Isobath Plot >70 68-70 66-68 64-66 62-64 60-62 58-60 56-58 54-56 52-54 50-52 48-50 46-48 <46 Spillway Crest All Shutters Lowered (A) Top Shutter Raised (T) Middle Shutter Raised (M) Bottom Shutter Raised (B) Lower River Outlet 09/01 09/30? = 1-9 hours of data missing A = All Shutters Lowered 1 AFD is a weighted average using hourly flow values! = 10 or more hours of data missing T = Top Shutter Raised 2 # = Station out of service M = Middle Shutter Raised 3 = Monthly Averages B = Bottom Shutter Raised 4 O = Unit Outage 5 6

D A T E Mean Daily Temperatures ( F) Water NFA ARP AFD 1 AHZ AWP AWB Air CSU Release (CFS) Nimbus Storage (TAF) Folsom Unit Shuter Position / Load Percentage Sep 63.1 57.9 61.0 62.1 64.5 65.2 70.0 1802 10/01? 63.4 58.6 62.3 62.8 65.0 65.5 70.4 1614 465 B 2 M 85 B 14 10/02 64.1 59.1 62.5 62.9 65.1 65.6 71.8 1360 464 B 2 M 84 B 14 10/03 65.9 56.6 62.6 63.0 65.1 65.6 69.0 1364 463 B 2 M 85 B 14 10/04 65.6 57.7 62.5 62.7 65.0 65.5 65.8 1371 461 B 1 M 83 B 15 10/05 65.8 58.4 62.7 62.8 64.7 64.8 64.4 1372 459 B 1 M 85 B 14 10/06 66.2 58.9 62.7 63.2 65.2 65.6 68.1 1358 458 B 1 M 84 B 14 10/07 65.0 57.4 63.2 63.1 64.4 64.5 67.5 1341 456 B 1 M 84 B 14 10/08 63.8 57.0 63.1 62.8 64.5 64.4 67.9 1359 454 B 1 M 86 B 13 10/09 63.5 57.8 63.1 62.9 64.6 64.7 66.7 1355 452 B 1 M 86 B 12 10/10 63.8 58.8 63.0 62.9 64.6 64.6 62.3 1327 449 B 1 M 83 B 15 10/11 63.9 59.5 62.9 63.0 64.7 64.8 62.9 1350 446 B 1 M 80 B 18 10/12 63.4 58.5 63.4 63.0 64.6 64.6 65.2 1376 445 B 1 M 86 B 13 10/13 62.7 56.9 63.1 62.9 64.5 64.5 65.4 1367 443 B 1 M 83 B 15 10/14 61.6 56.0 63.4 62.8 64.0 63.9 63.7 1350 441 B 1 M 80 B 18 10/15 60.2 54.9 62.9 62.7 63.5 63.0 63.2 1353 439 B 1 M 82 B 17 10/16 59.4 55.0 63.0 62.2 63.4 63.1 61.5 1446 436 B 5 M 79 B 16 10/17 58.9 54.9 63.1 62.2 63.5 63.3 62.3 1658 433 B 14 M 73 B 12 10/18 10/19 10/20 10/21 10/22 10/23 10/24 10/25 10/26 10/27 10/28 10/29 10/30 10/31 Oct 63.4 57.4 62.9 62.8 64.5 64.6 65.8 1395 Total AF 47050 Legend Notes Unit 1 Unit 2 Unit 3 Isobath Plot >70 68-70 66-68 64-66 62-64 60-62 58-60 56-58 54-56 52-54 50-52 48-50 46-48 <46 Spillway Crest All Shutters Lowered (A) Top Shutter Raised (T) Middle Shutter Raised (M) Bottom Shutter Raised (B) Lower River Outlet 10/01 10/31? = 1-9 hours of data missing A = All Shutters Lowered 1 AFD is a weighted average using hourly flow values! = 10 or more hours of data missing T = Top Shutter Raised 2 # = Station out of service M = Middle Shutter Raised 3 = Monthly Averages B = Bottom Shutter Raised 4 O = Unit Outage 5 6

Folsom Lake Temperature Profiles: 16-Oct-2018 460 440 Pool Elevation (Feet, msl) 420 400 380 360 340 320 300 280 260 240 Spillway Top - Top Shutters Top - Middle Shutters Top - Bottom Shutters W S Intake Power Penstocks Upper Tier River Outlets 220 Lower Tier River Outlets 200 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 Water Temperature ( F) Site A Site B Site C Site D Site E Site Dam

Storage, in TAF 1000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 Folsom Lake Isothermobaths - 2018 (Water Temperature, in F) 0 1/1 1/22 2/12 3/5 3/26 4/16 5/7 5/28 6/18 7/9 7/30 8/20 9/10 10/1 10/22 11/12 12/3 12/24 Date <46 46-48 48-50 50-52 52-54 54-56 56-58 58-60 60-62 62-64 64-66 66-68 68-70 >70

Folsom Cold Water Pool Folsom Reservoir: Cold Water Volume Profile Date Volume less than 58 o F (TAF) 10/16/18 45.1 Penstock Elevation (ft) Volume (TAF) Approximate Max. Temp (F) 327 83 63.0 Proposed Power Generation Bypass/Lower River Outlet for Temperature Management Date N/A at this time Bypass/Lower River Outlet (cfs) Temperature not to exceed downstream of Nimbus Dam ( o F) Cumulative Use of Cold Water Pool Volume (TAF)

DRAFT June 2018 90% Runoff Exceedance Outlook: Inflow based on 90% historical average runoff for all months. Federal End of the Month Storage/Elevation (TAF/Feet) Oct Nov Dec Jan Feb Mar Folsom 467 410 339 278 278 321 429 Elev. 404 394 383 383 391 407 Monthly River Releases (cfs) American 1507 1850 1850 1000 1045 1040 MRR 1500 1817 1817 50% Runoff Exceedance Outlook: Inflow based on 50% historical average runoff for all months. Federal End of the Month Storage/Elevation (TAF/Feet) Oct Nov Dec Jan Feb Mar Folsom 467 431 411 409 450 461 557 Elev. 408 405 404 410 412 423 Monthly River Releases (cfs) American 1802 1855 1850 1800 4500 3500 MRR 1500 1817 1817 Please note: CVP actual operations do not follow any forecasted operation or outlook; actual operations are based on real-time conditions. CVP operational forecasts or outlooks consider general system-wide dynamics and do not necessarily address specific watershed/tributary details. CVP releases represent monthly averages. CVP operations are updated monthly as new hydrology information is made available December through May. Shaded area represents less confident hydrologic inputs of the future water year. 10/18/2018

16000 14000 12000 10000 8000 6000 4000 2000 0 10/17/2018 1/7 1/14 1/21 1/28 2/4 2/11 2/18 2/25 3/4 3/11 3/18 3/25 4/1 4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29 8/5 8/12 8/19 8/26 9/2 9/9 9/16 9/23 9/30 10/7 10/14 10/21 10/28 11/4 11/11 11/18 11/25 12/2 12/9 12/16 12/23 12/30 Date 80 70 60 50 40 Release (cfs) / Volume (TAF) Temperature ( F) Sep 2018 90%-Exceedance Outlook USBR Pred. Temperature Schedule = 23 9/30 - CWP<60 (TAF, Constraint = 0) = <35 Number of Excursions = 0 9/30 - Folsom Storage (TAF) = 0 Max. Target Temp. = 65 All Down 1 Up 2 Up 3 Up Spillway Upper Lower Shortage Total Folsom Storage CWP60 Buffered Temp. Target Target Temp. - Watt Ave. Modeled Temp. - Folsom Modeled Temp. - Nimbus Modeled Temp. - Watt Ave. Air Temp.

16000 14000 12000 10000 8000 6000 4000 2000 0 10/17/2018 1/7 1/14 1/21 1/28 2/4 2/11 2/18 2/25 3/4 3/11 3/18 3/25 4/1 4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29 8/5 8/12 8/19 8/26 9/2 9/9 9/16 9/23 9/30 10/7 10/14 10/21 10/28 11/4 11/11 11/18 11/25 12/2 12/9 12/16 12/23 12/30 Date 80 70 60 50 40 Release (cfs) / Volume (TAF) Temperature ( F) Sep 2018 90%-Exceedance Outlook USBR Pred. Temperature Schedule = 23 9/30 - CWP<60 (TAF, Constraint = 0) = <35 Number of Excursions = 0 9/30 - Folsom Storage (TAF) = 0 Max. Target Temp. = 65 All Down 1 Up 2 Up 3 Up Spillway Upper Lower Shortage Total Folsom Storage CWP60 Buffered Temp. Target Target Temp. - Watt Ave. Modeled Temp. - Folsom Modeled Temp. - Nimbus Modeled Temp. - Watt Ave. Air Temp.

Proposal for Power Bypass October 11, 2018 California Department of Fish and Wildlife National Marine Fisheries Service US Fish and Wildlife Service American River Water Forum Issue: During the 2017 spawning season, adult fall-run Chinook returns to the Sacramento Valley were well below the conservation targets set by the Pacific Fisheries Management Council (PFMC), a multi-agency governing body to which the California Department of Fish and Wildlife (CDFW) and the National Marine Fisheries Service (NMFS) are members. These low returns throughout Sacramento Valley, including a near record low of 7,457 during 2017 on the American River in addition to spawner numbers in 2015 and 2016, prompted the PFMC to develop a stock rebuilding plan which evaluates the causes of the population decline and provides recommendations for rebuilding the stock. As stated in the March 6, 2018 letter from the National Marine Fisheries Service to the PMFC, The projected exploitation rates have also been lower than the post-season estimates. Spawner abundance has declined by an order of magnitude over the last five years from a high of 406,200 in 2013 to just 44,574 in 2017. The escapement in 2017 is near a record low. The three-year geometric mean of spawners is 76,714 and must increase to at least 122,000 to achieve rebuilt status. An escapement of 454,288 would be required to meet the FMP's criteria for rebuilt status in 2018. It is impractical to expect to achieve rebuilding so quickly, but progress can be made in 2018 toward that end. 1 To increase in-river production of fall-run Chinook salmon on the American River during 2018, water temperature management and management of the Folsom Lake s cold-water pool must improve, and operational planning must incorporate fall-run spawning temperature and flow needs. Proposed Action: To improve temperature management and help with stock rebuilding, the fish agencies (CDFW, U.S. Fish and Wildlife Service, and NMFS) and the Water Forum propose to utilize power bypass during November 2018 and continue that use until ambient air temperatures allow for suitable spawning temperatures to be achieved without power bypass. The fish agencies and the Water Forum are requesting that USBR schedule power bypass and implement other associated and necessary actions in advance of the need to implement power bypass. Logistical considerations to maximize temperature reduction benefits will be discussed at the October 18, 2018 ARG meeting and will include discussion of the most recent Folsom Lake temperature profile data, timing and magnitude of power bypass, and fall-run Chinook salmon presence and spawning maturity information. Based on discussions initiated during the August 16, 2018 meeting, the ARG expressed the desire and received commitment from the US Bureau of Reclamation (USBR) to discuss and plan ahead for fall flow and temperature targets based on the most up to date Folsom Lake thermal profile data and operational flexibility considerations, particularly the use of power bypass to achieve 1 https://wdfw.wa.gov/conservation/fisheries/chinook/noaa_comments_2017_plan/letter_pfmc_guidance_06031 8%20fnl.pdf

temperature reductions necessary to improve fall-run Chinook salmon spawning success and minimize temperature-related egg mortality. The temperature icpmm temperature modeling runs provided to ARG from USBR on October 5, 2018 show a temperature target of 59 F in November is achievable without the use of power bypass. This is in excess of the thermal optimum Chinook salmon spawning temperatures of 41-56 (Table 1). At the request of ARG, the Water Forum provided model runs to aid in understanding the thermal impact of various fall release schedules and investigating the thermal benefits of power bypass to evaluate the outcomes of multiple scenarios and the resulting temperature that would be achievable through November 2018. The Water Forum provided multiple modeling runs which were discussed at the October 5, 2018 ARG meeting based on inputs to the icpmm temperature model provided to the Water Forum from USBR on September 26 and updated on October 2. These modeling results indicate that even partial usage of the power bypass results in the ability to lower temperatures beginning November 1 in all flow and river gate (power bypass) operational scenarios (Appendix A). More specifically, a base flow of 1,500 cfs with river gate usage results in a temperature schedule ATSP -21 as per Appendix 2D of the NMFS biological opinion on the Coordinated Long-Term Operation of the Central Valley Project and State Water Project (NMFS 2009 BO) with minimal river gate usage reducing October and November temperature by 1 F to 58 F. Approximately, 6.8 TAF power bypass would pass through the river gates starting October 29, 2018 and additional river gate usage, as has been implemented in previous years (Appendix B), would further lower November temperatures. Justification: USBR is required to address American River temperature management as per the NMFS 2009 BO. While the NMFS 2009 BO is largely focused on temperatures for rearing lower American River steelhead, elevated water temperatures are also a major stressor for fall-run Chinook salmon, which are a species of concern under the federal Endangered Species Act (federal ESA). In 1992, the Central Valley Project Improvement Act modified the Central Valley Project purpose to include mitigation, protection, and restoration of fish and wildlife, including fall-run Chinook salmon. During summer months, warm surface water and cooler water below the surface in the reservoir (cold-water pool) are blended to meet the lower American River summer temperature limit for juvenile steelhead while releasing large volumes of stored water for exports and Bay-Delta water quality. The disproportionate volume of cold-water pool needed to achieve the summer temperature limit while releasing large volumes of stored water for exports frequently exhausts cold-water pool storage prior to fall-run Chinook salmon spawning, making it difficult to achieve suitable spawning temperatures. As demonstrated by the modeling results (Appendix A) temperature-related egg mortality can be avoided and minimized through the utilization of power bypass, resulting in significant benefit to fall-run Chinook salmon spawning and egg incubation success, as outlined in the Table 1 which is excerpted from the NMFS 2009 BO. 2

Table 1. Relationship between water temperature and mortality of Chinook salmon eggs and preemergent fry used in the Reclamation egg mortality model (reproduced from Table 6-14 in the NMFS 2009 BO, which was taken from the CVP/SWP operations BA table 6-2). Water Temperature Egg Mortalityb Instantaneous Daily Mortality Rate (%) Pre-Emergent Fry Mortalityb Instantaneous Daily Mortality Rate (%) (ΕF)a 41-56 Thermal optimum 0 Thermal optimum 0 57 8% @ 24d 0.35 Thermal optimum 0 58 15% @ 22d 0.74 Thermal optimum 0 59 25% @ 20d 1.40 10% @ 14d 0.75 60 50% @ 12d 5.80 25% @ 14d 2.05 61 80% @ 15d 10.70 50% @ 14d 4.95 62 100% @12d 38.40 75% @ 14d 9.90 63 100% @11d 41.90 100% @ 14d 32.89 64 100% @ 7d 65.80 100% @10dc 46.05 a This mortality schedule was compiled from a variety of studies each using different levels of precision in temperature measurement, the lowest of which was whole degrees Fahrenheit (+0.5oF). Therefore, the level of precision for temperature inputs to this model is limited to whole degrees Fahrenheit. b These mortality schedules were developed by the USFWS and CDFG for use in evaluation of Shasta Dam temperature control alternatives in June 1990 (Richardson et al. 1990) c This value was estimated similarly to the preceding values but was not included in the biological assumptions for Shasta outflow temperature control FES (Reclamation 1991b) 3

Appendix A American River - icpmm Temperature Modeling Fall 2018 4

Fall 2018 icpmm Temperature Modeling - 10/5/18 Objectives: Understand the thermal impact of various Fall release magnitudes Investigate thermal benefits of Power Bypass (aka River Gates) Approach Summary Base run provided by Peggy Manza on 9/26/18. Base run updated with 10/2/18 Temperature Profile. Inputs not verified for accuracy Same version of icpmm used as USBR Six alternatives tested o o o o o o 1500 cfs Oct-Dec - Resulting ATSP:23 1500 cfs Oct-Dec with River Gates - resulting ATSP:21 (lowest of all runs) 1750 cfs Oct-Dec - Resulting ATSP:23 1750 cfs Oct-Dec with River Gates - Resulting ATSP:22 1500 cfs Oct 1875 cfs Nov-Dec - Resulting ATSP:23 1500 cfs Oct 1875 cfs Nov-Dec with River Gates - Resulting ATSP:22 River Gates constrained to 500 cfs maximum (although they weren't used that much in any of the simulations), available 10/1 and beyond Standard ATSP temperature schedules used (no custom schedules tested) Results Summary Individual results are provided on following pages. River gate access improves ATSP in all cases and could lower temps in November even further if used at greater than 500 cfs. 1500 cfs with River Gates provides lowest temperatures but may conflict with MRR requirements. 5

Base (1500 cfs) no River Gates - ATSP:23 Base (1500 cfs) with River Gates - ATSP:21 Minimal River Gate usage reduces Oct and Nov temp schedule by 1 degree 6.8 TAF through River Gates starting 10/29 Additional River Gate usage could further lower November temperatures 6

1750 cfs No River Gates - ATSP: 23 Very similar to 1500 cfs run 1750cfs With River Gates - ATSP:22 minimal RG usage reduces Nov temp schedule by 1 degree 8.5 TAF through River Gates starting 10/29 Additional River Gate usage could further lower November temperatures one ATSP higher than 1500 cfs with River Gates run 7

MRR Flows (1500/1875 cfs) no River Gates - ATSP:23 very similar to 1500 and 1750 cfs runs MRR Flows (1500/1875 cfs) with River Gates - ATSP:22 minimal RG usage reduces Nov temp schedule by 1 degree 7 TAF through River Gates starting 10/29 Additional River Gate usage could further lower November temperatures 8

Appendix B Folsom Dam Power Bypass for Temperature Management 1998-2014 9

10

RE: Power Bypass Central Valley Project preference power customers who have a contractual entitlement or share of the Central Valley Project (CVP) power resource, pay a share of the fixed cost annually, plus the Restoration Fund charge, in exchange for the available CVP generation. CVP power customers are required to pay their share of the cost regardless of the amount of power delivered. When CVP power is not produced, power customers incur an additional cost to replace the CVP resource. This year assuming average hydro conditions, the effective cost of CVP power is about $25 per MWh, plus a Restoration Fund (Central Valley Project Improvement Act) charge of approximately $13 per MWh. Both charges increase if costs increase and when the CVP resource is constrained due to drought, by-passes, and forced outages. The greater the constraint on the CVP resource, the higher the CVP power cost, and, the increased requirement and cost for replacement power. Simply stated, when by-pass conditions exist, in FY 2019 CVP preference power customers are projected to pay approximately $38 per MWh for CVP energy, and incur an additional cost to replace the foregone CVP energy, today at a cost ranging in the low-to-mid $30 per MWh. By way of background, the Northern California Power Agency members collectively receive approximately 40 percent of the power output from the CVP. Our intent is to share with you, and the American River Group, the consequences to CVP power when water releases by-pass the CVP generators. The CVP hydropower generation is first used to meet the needs of water supply pumping and delivery, generally 25 percent. The remaining generation, about 75 percent, is then marketed by Western Area Power Administration in a manner that will encourage the most widespread use to CVP preference power customers. The term preference has meaning in Reclamation Law in that the sale of Federal power be given to certain entities, such as governments (state, Federal and Native American), municipalities, other public corporations or agencies, and cooperatives. Regina Rieger Federal Power Resource Program Manager