State Water Project Delivery Capability Report 2015

California Department of Water Resources (DWR) | July 1st, 2015

This report is intended to inform the public about key factors important to the operation of the State Water Project (SWP) and an estimate of its current delivery capabil

This report is intended to inform the public about key factors important to the operation of the State Water Project (SWP) and an estimate of its current delivery capability. For many SWP water contractors, water provided by the SWP is a major component of the water supplies available to them. SWP contractors include cities, counties, urban water agencies, and agricultural irrigation districts. These local utilities and other public and private entities provide the water that Californians use at home and work every day and that helps to nourish the state’s bountiful crops. Thus, the availability of water from the SWP is an important component to the water supply planning of its recipients and ultimately affects the amount of water that local residents and communities can use.

State Water Project Delivery Reliability Report (2005)

California Department of Water Resources (DWR) | April 27th, 2006

The State Water Project Delivery Reliability Report 2005 presents DWR’s current information regarding the annual water delivery reliability of the State Water Project (

The State Water Project Delivery Reliability Report 2005 presents DWR’s current information regarding the annual water delivery reliability of the State Water Project (SWP) for existing and future levels of development in the water source areas, assuming historical patterns of precipitation. This report first looks at the general subject of water delivery reliability and then discusses how DWR determines delivery reliability for the SWP. A discussion of the analysis tool (the CalSim II computer simulation model), the analyses, and peer review regarding the accuracy of CalSim II and its suitability for use in this report is included. Finally, estimates of SWP delivery reliability today and in the future are provided along with examples of how to incorporate this information into local water management plans. This report responds to a requirement in the settlement agreement with the Planning and Conservation League to provide an assessment of the existing delivery capability of the SWP over a range of hydrologic conditions. The range of conditions is to include the historic extended dry cycle and the long-term average. In addition, the biennial report is to include the total amount of project water delivered and the amount of project water delivered to each contractor for each of the 10 years immediately preceding the report.

State Water Project Delivery Reliability Report (2009)

California Department of Water Resources (DWR) | August 31st, 2010

The State Water Project (SWP) is primarily a water storage and delivery system intended to help close the gap in California between when and where precipitation primarily

The State Water Project (SWP) is primarily a water storage and delivery system intended to help close the gap in California between when and where precipitation primarily falls and when and where most water demands occur. Water from the SWP is a critical component of water supply for the 29 state water contractors, who may also receive water from other sources. While each of the water supply contracts defines the maximum amount of water to be delivered annually, the amount of water actually delivered may be less due to such factors as variable precipitation and runoff, physical and institutional limits on storage and conveyance, and contractors’ variable water demands. For communities receiving SWP water, the reliability of SWP water deliveries is a key factor for local planners and government officials estimating their own water supply reliability. The 2009 State Water Project Delivery Reliability Report (2009 Report) updates the information contained in the 2007 Report by estimating the amounts of water deliveries for Current Conditions and conditions twenty years in the future. These estimates incorporate restrictions on SWP and Central Valley Project (CVP) operations in accordance with the biological opinions of the U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) issued on Dec. 15, 2008 and June 4, 2009, respectively. The estimates for Future Conditions also incorporate potential changes in hydrology due to climate change projections recommended by the Climate Action Team and sea level rise. This report briefly describes the SWP and the Sacramento-San Joaquin Delta (Delta), the hub of water deliveries in California. It discusses the general topic of water delivery reliability and how Department of Water Resources (DWR) calculates delivery reliability for the SWP. It then summarizes key planning activities that may affect future SWP delivery reliability. Three areas of significant uncertainty for SWP delivery reliability are discussed. They are climate change and sea level rise, the vulnerability of Delta levees to failure, and operation restrictions imposed by the USFWS and NMFS in response to decreasing populations of endangered fish species. Next, the general approach taken to simulate SWP operations using CALSIM II is discussed. This report presents the results of CALSIM II studies and compares them to previous estimates. Finally, this report provides guidance on how to apply the delivery estimates to water management plans. Presented in appendices are detailed CALSIM II simulation assumptions and results and recent SWP deliveries. This report does not include analyses of how specific water agencies should integrate SWP water supply into their water supply equation. This topic requires extensive information about local facilities, local water resources, and local water use, which is beyond the scope of this report. Moreover, such an analysis would require deci sions about water supply and use that tradition ally have been made locally. DWR believes that local officials should continue to fill this role.

State Water Project Delivery Reliability Report 2007

California Department of Water Resources (DWR) | August 1st, 2008

The water delivery reliability of the State Water Project (SWP) is at a crossroads. Future water deliveries to millions of Californians throughout the state will be impac

The water delivery reliability of the State Water Project (SWP) is at a crossroads. Future water deliveries to millions of Californians throughout the state will be impacted by many factors. Two of the most significant changes facing the system are Delta pumping restrictions and climate change. This report provides a glimpse of our current path if no action is taken to address these and other factors affecting water delivery reliability. The report also identifies many other factors that could be changed to positively affect our water future. Estimating the delivery reliability of the SWP depends on many issues, including possible future regulatory standards in the Delta, population growth, water conservation and recycling efforts, and water transfers. The impact of climate change on hydrology, consumptive use of water, fisheries and sea level rise must also be considered. This report evaluates the impacts of potential changes in hydrology of climate change. These other factors also need to be considered in the future. The stability of Delta levees, and therefore, SWP water deliveries, are threatened by earthquakes, land subsidence and floods. On the positive side, there are significant and promising processes underway that could take us to a much more reliable and sustainable Delta water conveyance system for the SWP. In this report, a possible future for these factors is presented. However, to the extent that these factors can be and are changed by actions over the next few years, this estimate of water delivery reliability will also change.

State Water Project Delivery Reliability Report 2011

California Department of Water Resources (DWR) | June 1st, 2012

The State Water Project Delivery Reliability Report 2011 (2011 Report) is the latest update to a biannual report that describes the existing and future conditions for Sta

The State Water Project Delivery Reliability Report 2011 (2011 Report) is the latest update to a biannual report that describes the existing and future conditions for State Water Project (SWP) water supply that are expected if no significant improvements are made to convey water past the Sacramento–San Joaquin Delta (Delta) or to store the more variable runoff that is expected with climate change. This report is presented in a different format than previous versions. The four previous reports were written for a dual audience—both the general public and those interested in a greater level of technical detail, such as the SWP contractors. By contrast, this report is written primarily with the public in mind. As a result, it not only provides updated information about the SWP’s water delivery reliability, but is also designed to educate Californians about the SWP and its operations. This report presents a concise description of the historical events leading to the construction of the SWP and describes the SWP’s facilities and operations. It then defines and explains the concept of water delivery reliability and the types of SWP water available to contractors, and describes various factors that affect the reliability of water deliveries. Because of the public interest in water project pumping from the Delta and the dependence of SWP water supply on Delta pumping, a new chapter has been added that focuses specifically on SWP pumping (exports) at the Harvey O. Banks Pumping Plant in the Delta. The 2011 Report shows that the SWP continues to be subject to reductions in deliveries similar to those contained in the State Water Project Delivery Reliability Report 2009 (2009 Report), caused by the operational restrictions of biological opinions (BOs) issued in December 2008 and June 2009 by the U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) to govern SWP and Central Valley Project operations. Federal court decisions have remanded the BOs to USFWS and NMFS for further review and analysis. We expect that the current BOs will be replaced sometime in the future. The operational rules defined in the 2008 and 2009 BOs, however, continue to be legally required and are the rules used for the analyses supporting the 2011 Report. The following “Summary” includes key findings of the analyses in the 2011 Report. A technical addendum is also available which provides detail on the assumptions of the analyses and the results for the 2011 Report. The results of the studies, as presented in this report and the technical addendum, are designed to assist water planners and managers in updating their water management and infrastructure development plans. These results emphasize the need for local agencies to develop a resilient and robust water supply, and a distribution and management system to maximize the efficient use of our variable supply. They also illustrate the urgent need to improve the method of conveying water past the Delta in a more sustainable manner that meets the dual goals of increasing water delivery reliability and improving conditions for endangered and threatened fish species.

State Water Project Delivery Reliability Report 2013

California Department of Water Resources (DWR) | December 1st, 2014

This State Water Project Delivery Reliability Report 2013 updates the estimated water delivery capability of the State Water Project (SWP) for current conditions and two

This State Water Project Delivery Reliability Report 2013 updates the estimated water delivery capability of the State Water Project (SWP) for current conditions and two decades from now. The estimates include the best-known future effects of climate change and the anticipated changes in Sacramento River basin land uses. Climate change will alter the timing and magnitude of inflows to upstream storage facilities including Shasta, Folsom, and Oroville reservoirs. In addition, rising sea levels will pose operational challenges to maintaining suitable salinity levels in San Francisco Bay and the Sacramento–San Joaquin Delta (Delta). Other factors in our analysis of SWP reliability have been assumed to not change over time. They are too uncertain to incorporate into the analysis. For example, regulatory restrictions issued by the U.S. Fish and Wildlife Service and the National Marine Fisheries Service in their biological opinions are assumed to remain unchanged. The opinions dictate the timing and amounts of the SWP’s Delta exports. These restrictions are undergoing further review and analysis under a federal court order. Also, the Delta water quality and flow requirements contained in the State Water Resources Control Board’s water quality control plan for the Delta are assumed to remain unchanged. However, the board is revising its water quality control plan. Revisions to the plan and their subsequent inclusion into the California Department of Water Resources’ (DWR’s) water rights for the SWP could have a significant effect on SWP deliveries. The estimates in this report can be used by water districts as part of the analyses for their water management plans, which are required by State legislation to be updated in 2015. The report includes estimates for a range of hydrologic conditions that should be considered in water management plans. These estimates do not incorporate the risk of a disruption in SWP deliveries caused by catastrophic failure of Delta levees. Delta levee failure as a result of floods, earthquakes, erosion, or rising sea levels could interrupt water deliveries from the Delta for weeks, months, or even years, depending on the nature and the scope of the failure. Water management plans should describe the response to this potential scenario. This assessment of current and future SWP reliability is one of several efforts by DWR to help plan for reliable future water supplies in California.

Statement from ADWR Director Tom Buschatzke and CAP General Manager Ted Cooke in response to the U.S. Department of the Interior announcement of actions to protect the Colorado River system and 2023 Operating Conditions for Lake Powell and Lake Mead

Arizona Department of Water Resources (ADWR) | August 16th, 2022

Statement of Camille Calimlim Touton, Commissioner, Bureau of Reclamation U.S. Department of the Interior Before the Senate Committee on Energy and Natural Resources June 14, 2022

Senate Committee on Energy and Natural Resources | June 14th, 2022

"The Colorado River Basin is in the 23rd year of a historic drought. Both Lake Powell and Lake Mead – the two largest reservoirs in the United States – are at histori

"The Colorado River Basin is in the 23rd year of a historic drought. Both Lake Powell and Lake Mead – the two largest reservoirs in the United States – are at historically low levels with a combined storage capacity of 28 percent of capacity. While Reclamation and its partners have been successful in conserving water in Lake Mead and Colorado River System reservoirs, more needs to be done as the system reaches critically low water levels. The system is at a tipping point. An example of how Tribal Nations and water managers have addressed these conditions is shown in how, over the past 15 years, approximately 4.6 million acre-feet (maf) have been conserved in Lake Mead through voluntary measures by the three Lower Basin States, Tribal Nations, and Mexico. This has been accomplished through the creation of Intentionally Created Surplus, system conservation water, water for Mexico’s water reserve under Minutes 318, 319, and 323, as well as other water conservation efforts. At current water levels, these measures add 70 feet to Lake Mead’s elevation and delayed the first shortage declaration by six years. Over the past few years, Reclamation has worked with the Upper and Lower Basin States, Tribes, and stakeholders on Colorado River Drought Contingency Plans (DCPs), which were implemented in 2019. The DCPs provide a framework for additional actions to help the basin adapt to drought. An example of this is a 2021 Lower Basin Memorandum of Understanding, called the 500 Plus Plan. The plan, developed under both the DCP and 2021 MOU, aims to conserve additional water above what is required under a Lower Basin shortage condition and contributions under the Lower Basin DCP. The 500 Plus Plan parties have identified and are funding projects in each of the three Lower Basin States, and the projects include tribal, agricultural, and municipal water users. On May 3, 2022, Reclamation announced two separate drought response actions that will help increase Lake Powell storage by nearly 1.0 maf over the next 12 months (May 2022 through April 2023). The two actions include: 1. Approximately 500,000 acre-feet of water will be released from Flaming Gorge Reservoir, located approximately 455 river miles upstream of Lake Powell, pursuant to an agreement as part of the Upper Basin Drought Contingency Plan (adopted in 2019); and 2. Another 480,000 acre-feet will be left in Lake Powell by reducing Glen Canyon Dam’s annual release volume from 7.48 maf to 7.00 maf, as outlined in the 2007 Interim Guidelines that control operations of Glen Canyon Dam and Hoover Dam. Regarding current conditions, in March 2022 Lake Powell dropped below elevation 3,525 feet, meaning the reservoir was less than 35 feet above the minimum power pool of 3,490 feet (i.e., minimum elevation at which hydropower can be generated). According to the May 2022 Most Probable 24-Month Study, the April-July runoff forecast into Lake Powell is 3.80 maf, or 59 percent of average. Lake Powell’s water surface elevation is projected to end the calendar year at 3,522.94 feet (22 percent full). Lake Mead is projected to reach an elevation of 1,039.92 feet (27 percent full) on December 31, 2022. While not official until the August 2022 24-Month Study, a shortage condition for the Lower Basin is projected in calendar year 2023. Looking to the future, Reclamation is preparing to develop new operating guidelines given that the 2007 Interim Guidelines expire in 2026. Reclamation is targeting initiating a formal National Environmental Policy Act (NEPA) process in early 2023. Technical information and lessons learned from management under the current guidelines will be very helpful as the basin strives to develop new guidelines that are durable and drought resilient. Additionally, collaboration and involvement by partners and stakeholders (Tribal Nations, States, water districts, etc.) will be paramount for the effort to be successful. Prior to the start of the formal NEPA process, Reclamation is preparing to issue a “pre-scoping” Federal Register notice (targeting the week of June 20) to ask for input on both the stakeholder engagement process and the substantive elements and strategies for post-2026 operations. Despite the actions taken by the Department and Reclamation, significant and additional conservation actions are required to protect the Colorado River system infrastructure and the long-term stability of the system."

Still Imperilled, Still Important: The Little Hoover Commission’s Review of the CALFED Program

Little Hoover Commission | November 17th, 2005

The Sacramento-San Joaquin River Delta is a treasured and imperiled resource. And CALFED has been the best hope to restore it. The ambitious state-federal partnership is

The Sacramento-San Joaquin River Delta is a treasured and imperiled resource. And CALFED has been the best hope to restore it. The ambitious state-federal partnership is proof that political will and leadership can resolve seemingly intractable conflicts. And yet in recent years, the program also has demonstrated the propensity for rudderless bureaucracies to get caught in inescapable eddies. It is not too late for the Delta, or for CALFED. But restoring the estuary and managing the resource in a sustainable manner will require continuous political support, expert leadership, and smart management.

Storing and managing water for the environment is more efficient than mimicking natural flows

Nature Portfolio (Springer Nature) | June 27th, 2024