Competing objectives for the Colorado River Can we have it all?

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1 Competing objectives for the Colorado River Can we have it all? Can science show us the way? Jack Schmidt Center for Colorado River Studies Department of Watershed Sciences Utah State University

2 Why have hope? The role of applied science and engineering in finding a path forward

3 High Country News, long ago The Colorado River as river The Colorado River as water Yampa River in Dinosaur National Monument (photo by W. Wurtsbaugh)

4 The general course of the river is from north to south and from great altitudes to the level of the sea. Thus, it runs from the land of snow to the land of sun. John Wesley Powell (1895) Lees Ferry 14.7M af Green River 5.3M af Cisco 6.7M af Greendale 1.9M af Glenwood Springs 2.1M af Grand Junction 2.3M af Bluff 2.1M af Yuma 18.2M af

5 Water source Grand Canyon Senior water users Why have hope? Water rights and water allocation

6 national park national monument national recreation area Why have hope? National Park and Monument system

7 Why have hope? An endemic and endangered fish community

8 Historical Supply and Use 1 and Projected Future Colorado River Basin Water Supply and Demand 1 The effects of climate change are uncertain Demand for Colorado River water will increase, primarily in relation to regional population growth 1 Water use and demand include Mexico s allotment and losses such as those due to reservoir evaporation, native vegetation, and operational inefficiencies. (USBR, 2012) It is important to recognize two points concerning this result. First, the 3.2 maf imbalance is based on the median imbalance for a particular year and can either be more or less from year to year under any one of the projections. Second, single-year imbalances of this magnitude have occurred several times in the past. Although there have been shortages in supply in Upper Basin tributaries, Colorado River deliveries of basic apportionments in the Lower Basin have been made with 100 percent reliability, primarily as a result of the ability to capture water in system reservoirs during high-flow years and to deliver that water during Why have hope? low-flow years. The system reliability analysis entailed simulating the operation of the system, including the effects to reservoir storage, and provides detailed Impending information water supply or water allocation crisis regarding the specific timing and magnitude of potential imbalances and how the Basin

9 The legacy of natural science and engineering

10 What river science and engineering have taught us Ecosystem drivers and conditions changed by large dams: Longitudinal connectivity Flow regime Sediment supply Temperature Glen Canyon Dam closed in March 1963

11 The river network has been fragmented. Longitudinal connectivity for many of the wideranging fish species will probably never be restored CA NV Salton Sea Lake Mead Lake Mohave UT Lake Powell Lees Ferry AZ Flaming Gorge Reservoir CO Navajo Reservoir NM

12 In some places, stream flow has been greatly depleted DISCHARGE, IN CUBIC METERS PER SECOND Colorado River blw Yuma main canal w. w. at Yuma, AZ cms Colorado River at Yuma, AZ cms I DAY OF THE YEAR The Delta

13 Discharge (m 3 /s) 50!. In some places, stream flow has been greatly depleted!.!.! (25% - 75%) (50%) (25% - 75%) (50%) 20 Streamflow depletion on the San Rafael River, Utah due to upstream irrigation Days after January 1

14 Elsewhere, the total annual flow has changed little but the flow regime has been greatly changed Colorado River at Lees Ferry Because much of the water flows to the lower basin, the primary changes in the flow regime are caused by flood control, changes in the season of high flow, and hydropeaking 1) Reduce the magnitude of floods 2) Increase the magnitude of base flows 3) Introduce daily tides associated with hydropower production 4) Do not change the annual volume of stream flow (Topping et al., 2003)

15 The natural delivery of fine sediment to the delta has been cutoff by Lake Powell and Lake Mead Fine sediment delta in Lake Powell near Hite Estimated average suspended sediment discharge ~1700, before significant human impact (Meade et al., 1990)

16 Downstream channel changes caused by dams are determined by the relative change in the capacity to transport sediment and the sediment supply available to be transported Sediment surplus, San Rafael River 1973 Sediment deficit, Colorado River in Grand Canyon 2009

17 water Sediment deficit Sediment surplus Sediment deficit sediment Sediment surplus Dams in different parts of the watershed affect different proportions of the stream flow and sediment supply

18 Spillways 3648 (Warm) Powerplant 3470 (Cold/Warm) River Outlets 3374 (Cold) Releases from large reservoirs are typically much colder than conditions in summer and warmer in winter Releases from Glen Canyon Dam

19 Upper Colorado River Endangered Fish Recovery Program ( ) [$161 mil ~$7 mil./yr;] San Juan River Basin Recovery Implementation Program ( ) [$34.6 mil ; $2.1 mil FY06] Lower Colorado River Multi-Species Conservation Program ( ) $620 mil. (50 yrs) ~$13 mil./yr Glen Canyon Dam Adaptive Management Program $11 mil./yr operating ~$40 mil./yr lost revenue Minute 319, 1944 Water Treaty Present efforts to mitigate adverse impacts of water supply development

20 controlled floods Reduced range in daily range of hydropeaking Increase base flows Release controlled floods

21 The principal source of sand to the Colorado River is the Paria River whose confluence is at Lees Ferry, 25 km downstream from the dam. The Paria provides the largest supply of sand to the regulated Colorado River downstream from Glen Canyon Dam. A bit about controlled floods

22 A conceptual plan to take immediate advantage of the incoming Paria River sand supply was proposed by USGS/GCMRC in Environmental Assessment Protocol for High-Flow Experimental Releases This plan was approved in summer 2012 as the High Flow Protocol (HFE Protocol). 400 LCR Spring Accounting Period 350 Spring HFE Window (Mar/Apr) Short-duration controlled floods redistribute sand from low to high elevation Fall Accounting Period Fall HFE Window (Oct/Nov) Allow sand from the Paria River accumulates during an accounting season Average Monthly Sand Load (thousands of metric tons) Paria JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN

23 Implementation of the High Flow Experiment Protocol requires unprecedented collection of processing of stream-flow and sedimenttransport data in real time to inform operational decisions about dam releases and power marketing

24 These data are assembled and reported as mass balance sand budgets for 6 segments of the Colorado River ecosystem. Making science transparent and accessible

25 Transparent data distribution revealing uncertainties. Data are made available in an interactive web tool that allows the user to define computation periods and uncertainties.

26 Decisions about implementing controlled floods must be made in late October in order to provide advance notice to redistribute water releases and to reallocate hydropower production. Most, but not all, Paria flash floods have occurred by this time, and sand mass balance budgets are only available through September 30. Controlled floods must be planned in a way that acknowledges uncertainty. Cooperation between science, engineering, and public policy Graphs were developed in late September and used as planning tools to estimate the amount of sand mobilized by hypothetical HFEs.

27 Identifying an acceptable threshold in the range of daily load-following fluctuations to recreate a healthy food base Kennedy et al., 2016

28 Existence of a large dam Reservoir operations Complete trapping of incoming sediment Flow regime changes Flood control Increase in base flow hydropeaking Temperature regime changes Increase winter water temperature Decrease summer water temperatures The effects of large dams and reservoirs are caused by changes in flow regime and sediment supply that are related to water supply and hydroelectric power production

29 Existence of a large dam Reservoir operations Change rules concerning which reservoirs store water; change allocation agreements Restore sediment supply by sediment by-pass Change flood control rules Eliminate fragmentation caused by dams Flow regime changes Controlled floods Change seasonality of flows Temperature regime changes Increase summer water temperature Decrease decrease winter water temperatures Reduce or eliminate hydropeaking

30 Existence of a large dam Reservoir operations Change rules concerning which reservoirs store water; change allocation agreements Restore sediment supply by sediment by-pass Change flood control rules Eliminate fragmentation caused by dams Flow regime changes Controlled floods Change seasonality of flows Temperature regime changes Increase summer water temperature Decrease decrease winter water temperatures Reduce or eliminate hydropeaking Most adjustments in dam management have been focused on changing reservoir operations, not on changing water-supply management.

31 There is no societal consensus to transfer fine sediment from Lake Powell to Grand Canyon Addition of 4.3 x 10 6 Mg/yr by dredging and pipeline; appraisal level cost estimates Slurry pipeline Navajo Canyon to Glen Canyon Dam ($220 million capital costs; $6.6 million annual operating cost) Slurry pipeline Navajo Canyon to Lees Ferry ($430 million capital costs; $17 million annual operating cost) Randle et al, 2007

32 Long segments of western US rivers are now perturbed into sediment deficit. Elsewhere, surplus exists. Reservoir releases for any environmental or watersupply purpose have the potential to exacerbate or ameliorate sediment deficit or surplus conditions and ought to be monitored. Sediment gaging network outside of Grand Canyon primarily funded by Park Service. Funding base needs to be expanded. (Schmidt and Wilcock, 2008)

33 Cataract Canyon Hoover Dam Lake Mead Glen Canyon Lake Powell Glen Canyon Dam Grand Canyon Marble Canyon Reconsider how water is stored in Lake Powell and Lake Mead equalization or preferential storage in Lake Mead

34

35 Fill Mead First Proposal Phase I reduce storage in Lake Powell to minimum power pool elevation (surface area of reservoir is 31% of full pool surface area) Phase II reduce storage in Lake Powell to dead pool (surface area of reservoir is 13% of full pool surface area) Phase III drill new diversion tunnels and fully drain Lake Powell Expose Glen Canyon s sandstone walls Recreate natural flow regime Save water

36 Would a natural flow regime be established in Grand Canyon? How much of Glen Canyon would be exposed? 3,520 Capacity of River Outlets at Different Reservoir Elevations ELEVATION, IN FEET ABOVE MEAN SEA LEVEL 3,500 minimum power pool 3,480 3,460 3,440 3,420 3,400 3,380 4,000 6,000 8,000 10,000 12,000 14,000 16,000 CAPACITY OF RIVER OUTLETS, IN CUBIC FEET PER SECOND The limited capacity of the penstocks and river outlets would prevent a natural flow regime from being reestablished in Grand Canyon. Data: Bureau of Reclamation

37 In Phase I of FMF, part of the incoming snowmelt flood would be temporarily stored in Lake Powell

38 Inflow(cfs) Elevation (ft) Flow (cfs) Inflow from Upstream Outflow Phase II In Phase II of FMF, most of the incoming snowmelt flood would be stored in Lake Powell and it might take >1 year to release that water downstream 0 1/1/08 2/1/08 3/1/08 4/1/08 5/1/08 6/1/08 7/1/08 8/1/08 9/1/08 10/1/08 11/1/08 12/1/08 Inflow from Upstream Elevation /1/08 2/1/08 3/1/08 4/1/08 5/1/08 6/1/08 7/1/08 8/1/08 9/1/08 10/1/08 11/1/08 12/1/

39 Mar-64 Mar-66 Mar-68 Mar-70 Mar-72 Mar-74 Mar-76 Mar-78 Mar-80 Mar-82 Mar-84 Mar-86 Mar-88 Mar-90 Mar-92 Mar-94 Mar-96 Mar-98 Mar-00 Mar-02 Mar-04 Mar-06 Mar-08 Mar-10 Mar-12 Mar-14 Mar-16 Inflow (cfs) Elevation (ft) Inflow to Lake Powell Phase II Reservoir Elevation Date In Phase II of FMF, Lake Powell would rarely be at dead pool elevation

40 Flow (cfs) Inflow to Lake Powell Phase II Outflow The flow regime in Grand Canyon would be very different from the natural regime in Phase II.

41 Phase I Phase II The lower reservoir levels of Phase I and Phase II would cause the San Juan and Colorado Rivers to incise into their deltas. The mobilized fine seidment would form new deltas within the lowered reservoir. Downstream releases would be clear water.

42 1 EVAPORATION RATE, IN FEET PER MONTH Would Fill Mead First Save Water? 1 ( ) ( ) ( ) 0.2 ( ) (CRSS) EVAPORATION RATE, IN FEET PER MONTH ( ) ( ) Ja F Mar Ap May Jun Jul Au S O N D Evaporation measurements at Lake Powell and Lake Mead Evaporation pans Water budgets Mass transfer Eddy covariance 0 Ja F Mar Ap May Jun Jul Au S O N D

43 1 EVAPORATION RATE, IN FEET PER MONTH Lake Mead ( ) eddy covariance measurements Lake Powell ( ) mass transfer measurements 0 Ja F Mar Ap May Jun Jul Au S O N D Most recent evaporation measurements at each reservoir

44 180, ,000 LAKE POWELL SURFACE AREA, IN ACRE FEET 140, , ,000 80,000 60,000 Minimum Power Pool LAKE MEAD 40,000 20, ,000,000 10,000,000 15,000,000 20,000,000 25,000,000 30,000,000 TOTAL RESERVOIR STORAGE, IN ACRE FEET Reservoir surface area in relation to storage contents

45 30,000,000 LAKE POWELL AND LAKE MEAD TOTAL RESERVOIR STORAGE, IN ACRE FEET 10,000,000 20,000,000 30,000,000 40,000,000 50,000,000 STORAGE IN LAKE POWELL, IN ACRE FEET 25,000,000 20,000,000 15,000,000 10,000,000 5,000,000 Equalization Fill Mead First - Phase I Fill Mead First - Phase II 30,000,000 LAKE POWELL AND LAKE MEAD TOTAL RESERVOIR STORAGE, IN ACRE FEET 10,000,000 20,000,000 30,000,000 40,000,000 50,000, PROPORTION OF TOTAL LAKE POWELL AND LAKE MEAD LIVE STORAGE Assumed allocation of storage under different management schemes STORAGE IN LAKE MEAD, IN ACRE FEET 25,000,000 20,000,000 15,000,000 10,000,000 5,000,000 Fill Mead First - Phase II Fill Mead First - Phase I Equalization PROPORTION OF TOTAL LAKE POWELL AND LAKE MEAD LIVE STORAGE

46 200,000 LAKE POWELL AND LAKE MEAD TOTAL RESERVOIR STORAGE, IN ACRE FEET 10,000,000 20,000,000 30,000,000 40,000,000 50,000,000 SURFACE AREA OF LAKE POWELL, IN ACRES 150, ,000 50,000 Fill Mead First - Phase I Equalization Fill Mead First - Phase II PROPORTION OF TOTAL LAKE POWELL AND LAKE MEAD LIVE STORAGE Surface area of each reservoir under different management schemes SURFACE AREA OF LAKE MEAD, IN ACRES 200, , ,000 50,000 LAKE POWELL AND LAKE MEAD TOTAL RESERVOIR STORAGE, IN ACRE FEET 10,000,000 20,000,000 30,000,000 40,000,000 50,000,000 Fill Mead First - Phase II Fill Mead First - Phase I Equalization PROPORTION OF TOTAL LAKE POWELL AND LAKE MEAD LIVE STORAGE

47 SURFACE AREA OF LAKE POWELL AND LAKE MEAD, IN ACRES 350, , , , , ,000 50,000 LAKE POWELL AND LAKE MEAD TOTAL RESERVOIR STORAGE, IN ACRE FEET 10,000,000 20,000,000 30,000,000 40,000,000 50,000,000 Equalization Fill Mead First - Phase II Fill Mead First - Phase I PROPORTION OF TOTAL LAKE POWELL AND LAKE MEAD LIVE STORAGE Implementation of FMF would reduce the surface area of reservoir storage

48 LAKE POWELL AND LAKE MEAD TOTAL RESERVOIR STORAGE, IN ACRE FEET 15,000,000 20,000,000 25,000,000 30,000,000 TOTAL EVAPORATION FROM LAKE POWELL AND LAKE MEAD, IN ACRE FEET PER YEAR 1,400,000 1,200,000 1,000, , ,000 Equalization Fill Mead First - Phase I Fill Mead First - Phase II Evaporation losses might be reduced if water is preferentially stored in Lake Mead rather than distributing the water in both reservoirs, but uncertainty is very high PROPORTION OF TOTAL LAKE POWELL AND LAKE MEAD LIVE STORAGE

49 Jacoby et al., 1977 Movement of reservoir water into ground-water storage is inevitable

50 Ground-water flow patterns surrounding Lake Powell Blanchard, 1986 Thomas, 1986

51 Thomas, 1986 A B Estimated perturbations of ground-water flow patterns near Glen Canyon Dam

52 ANNUAL RATE OF GROUND-WATER STORAGE ACCUMULATION, IN MILLIONS OF ACRE FEET PER YEAR 1 Jacoby et al., 1977 Myers, 2013 Thomas, ? Estimated water savings associated with lowering or draining Lake Powell are based on assuming that past rates of ground-water storage will continue in the future. This is unlikely. Future ground-water movement estimated 50,000 af/yr, decreasing to 30,000 af/yr after mid-century.

53 What is groundwater storage like surrounding Lake Mead? No modern studies of movement patterns Wiele et al., 2009

54 Findings: Implementation of Phase I or Phase II of FMF is unlikely to re-establish a natural flow regime of the Colorado River in Grand Canyon Water released from a partially drained Lake Powell in Phase I or Phase II would be devoid of fine sediment. Impacts to the aquatic and riparian ecosystem, including to the existing population of endangered humpback chub, are potentially significant and would have to be monitored and managed adaptively. For purposes of public policy discussion at this time, there would be no change in evaporation losses if FMF was implemented. Based on the best estimates of the most recent USGS study, the long-term future rate of movement of ground water into the bedrock surrounding Lake Powell is likely to be less than ~50,000 af/yr.

55 Now is the time to initiate new measurement programs of losses at Lake Powell and Lake Mead so that future policy discussions have access to less uncertain data regarding evaporation and ground-water storage initiation of a new measurement program of evaporation at Lake Powell continuation of the present evaporation measurement program at Lake Mead initiation of a new phase of ground-water monitoring and modeling at Lake Powell and perhaps at Lake Mead, including establishment of new observation wells further from and to the south of Lake Powell, coupled by development of modern, state-of-the-science numerical models of groundwater flow establishment of a new gaging station to reduce uncertainty in estimating the amount of unmeasured inflow to Lake Powell implementation of FMF would have to be preceded by predictive modeling of fine-sediment redistribution within a partially drained Lake Powell so that reservoir releases would not further degrade the Grand Canyon ecosystem.

56 Is the role of river science to dash the hopes for innovation in river and water policy? Good ideas often start out as crazy ideas

57 Pulse flow release from Morelos Dam into the Delta in March The intellectual roots of the delta pulse flow

58 The intellectual roots of controlled floods One role of science is to flesh out conceptual ideas and refine them

59 Glen Canyon Dam Adaptive Management Program Secretary of the Interior Secretary s designee Glen Canyon Dam Adaptive Management Program (GCDAMP) Adaptive Management Work Group Technical Work Group Arizona California Colorado New Mexico Nevada Utah Wyoming Bureau of Indian Affairs Bureau of Reclamation National Park Service Fish and Wildlife Service Hopi Hualapai Navajo Southern Paiute Zuni Colorado River Energy Distributors Association Federation of Fly Fishermen Grand Canyon River Guides Grand Canyon Wildlands Council National Parks Conservation Association Utah Association of Municipal Power Systems Western Area Power Administration Arizona Department of Game and Fish

60 Secretary of the Interior An organizational framework for agency science (the past) Secretary s Designee Adaptive Management Work Group USGS Grand Canyon Monitoring and Research Center Individual stakeholders Technical Work Group Bureau of Indian Affairs Bureau of Reclamation National Park Service Fish and Wildlife Service Western Area Power Administration Arizona Department of Game and Fish

61 Secretary of the Interior An organizational framework for agency science (the present) Secretary s Designee Adaptive Management Work Group USGS Grand Canyon Monitoring and Research Center Individual stakeholders Technical Work Group Bureau of Indian Affairs Bureau of Reclamation National Park Service Fish and Wildlife Service Western Area Power Administration Arizona Department of Game and Fish

62 Responsive to the immediate information needs of present decisions Identifying the questions relevant to the future Adaptive Management programs NGOs (enviros, resource users, recreation) Federal/ state/ university science Federal agencies A framework for Colorado River Science science State wildlife and water resource agencies

63 There is hope, because there is water Science-based strategies are being implemented to improve ecosystem conditions in some parts of the river system Today, we primarily implement changes in hydroelectricity generation but we may eventually need to consider changing water-supply strategies Good ideas sometimes don t start out that way. Even the Fill Mead First proposal has some merit. Some applied science is in direct support of agency and adaptive management information needs. Other applied science work is needed to identify the next generation of questions that society will someday ask.