Atmospheric River Precipitation Enhanced by Climate Change: A Case Study of the Storm That Contributed to California's Oroville Dam Crisis

American Geophysical Union (AGU) | February 9th, 2022

California's reliance on precipitation from atmospheric rivers is expected to increase as our climate warms. Understanding how climate change is impacting this increasing

California's reliance on precipitation from atmospheric rivers is expected to increase as our climate warms. Understanding how climate change is impacting this increasingly dominant mode of precipitation is vitally important for water-resource management throughout the state, across the North American West Coast, and for other similarly impacted regions. Our case study of an impactful atmospheric river from early February 2017 that contributed to the Oroville Dam crisis in Northern California, modeled under preindustrial, present-day, mid-, and late-21st century unabatedly warming environments, demonstrates an overwhelming increase in precipitation throughout the event. This particular storm was comprised of two distinct pulses, and while both pulses of the storm are enhanced in the warmer future epochs, the estimated precipitation increases are disproportionately higher for the second pulse due to larger increases in temperature and moisture. Our results therefore suggest that not all atmospheric rivers are similarly affected by climate change and point to specific directions for relevant future research.

Averting disaster: Action now for the Salton Sea

Little Hoover Commission | September 1st, 2015

The Salton Sea is shrinking. Currently the state’s largest inland body of water, as it dries up, the Sea poses a substantial threat to public health and the environment

The Salton Sea is shrinking. Currently the state’s largest inland body of water, as it dries up, the Sea poses a substantial threat to public health and the environment. Left unaddressed, desert winds will lift dust from thousands of acres of newly-revealed lakebed and blow it into population centers, agricultural areas and world-class resort economies. This impending crisis is long in the making, a policy paralysis driven by years of government process without implementing a fix. There are clear, understandable and specific mitigation steps that should be taken immediately. The decisions California leaders make in the near future about this remote desert lake will determine whether this dismal scenario will be averted. The Commission urges the Natural Resources Agency to begin implementing shovel-ready projects and the Governor and Legislature to immediately begin planning and funding the next phase of Salton Sea projects while developing a long-term restoration plan. ... When California signed the QSA, it agreed to mitigate the impacts on the Salton Sea caused by the water transfers. The state clarified its intent to restore the sea through the QSA’s implementing legislation. Experts testified it would be tens of billions of dollars cheaper to mitigate the impacts of a shrinking sea up front than to deal with the adverse impacts of inaction. Fulfilling California’s commitment to the Salton Sea is an element of maintaining the terms of the QSA, which provides water security to many Californians. Continued inaction, and the consequent public health and environmental impacts, could undermine political support for the QSA. Further, in the larger picture, California’s fulfillment of its commitments is critical to its ability to negotiate future difficult agreements. ...    

Bay Delta Plan Phase 2 Workshop Summary Report

California State Water Resources Control Board (SWRCB) | January 1st, 2013

The California State Water Resources Control Board (Board) is tasked with updating the 2006 Water Quality Control Plan for the Bay-Delta Estuary (Bay-Delta Plan). The Boa

The California State Water Resources Control Board (Board) is tasked with updating the 2006 Water Quality Control Plan for the Bay-Delta Estuary (Bay-Delta Plan). The Board planning activities for this process have four phases. Phase 1 focused on San Joaquin River flow requirements and southern Delta water quality objectives. The current phase (Phase 2) focuses on fish and wildlife beneficial uses. Phase 3 will focus on modifications to water rights and Phase 4 will focus on the development and implementation of flow requirements for priority Delta tributaries. Phase 2 workshops were held to conduct discussions and generate information regarding the scientific and technical basis for considering potential changes to the Bay-Delta Plan. The workshops were informal; the Board did not take any official action and there was no sworn testimony. Information provided during the workshops will augment information developed through earlier reviews and will inform the Board members and staff on what, if any, changes should be made to the Bay-Delta Plan. Three workshops were held. Full workshop agendas are provided in Appendix A. 1. Ecosystem Changes and the Low Salinity Zone, September 5–6, 2012 – including the effects of the low salinity zone on various estuarine species, the interaction of salinity with non-flow related factors, and the identification of modeling or other tools that can be used to measure and reasonably protect estuarine habitat. 2. Bay-Delta Fishery Resources, October 1–2, 2012 – including flow, cold water pool, habitat, and water project operational constraints needed to reasonably protect Central Valley steelhead, Sacramento River winter-run, Central Valley late fall–run Chinook salmon, and pelagic species (including Delta smelt and longfin smelt); and the interaction of these issues with non-flow related factors. 3. Analytical Tools for Evaluating the Water Supply, Hydrodynamic, and Hydropower Effects of the Bay-Delta Plan, November 13–14, 2012 – including the CalSim II water supply model, DSM2 and RMA2 hydrodynamic models, Plexus hydropower model, and others as  applicable, together with results from applying these models to various scenarios.

Beyond Privatization: Restructuring Water Systems to Improve Performance

Pacific Institute | December 1st, 2005

Water managers face significant challenges meeting the water supply, wastewater collection and treatment, and stormwater management needs of the communities they serve. N

Water managers face significant challenges meeting the water supply, wastewater collection and treatment, and stormwater management needs of the communities they serve. Numerous solutions have been proposed, including privatization—the controversial action of significantly increased private sector involvement. The debate over privatization overshadows discussion of the determinants of performance. Pacific Institute’s report Beyond Privitization: Restructuring Water Systems to Improve Performance  finds that public versus private is not the bright line that separates success from failure. Researchers Gary Wolff and Eric Hallstein found that performance depends on effective staffing, consistent public support for sufficient funding, better asset management systems, performance measurements and rewards, and more stakeholder involvement and transparency. When increased private involvement or changes in public operations create significant cost savings, as they have in some cases, it is because specific improvements were identified and implemented in one or more of these categories. Beyond Privatization provides a framework for urban and rural municipal-level public decisionmakers to assess problems, identify possible solutions, and choose among these solutions. It provides practical information and examples about improving the effectiveness of water, wastewater, and stormwater systems, whether public or private. To illustrate critical points, the report offers numerous examples from the upper Midwest: the US states of Illinois, Indiana, Iowa, Michigan, Minnesota, Ohio, and Wisconsin, and the Canadian province of Ontario. However, the manual’s lessons extrapolate to other regions of the United States, and beyond.

Beyond Water Pricing: An Overview of Water Financing Options in California

Pacific Institute | November 21st, 2013

California’s social and economic well-being is directly tied to financing for reliable, sustainable water. A new study from the Pacific Institute explores stable and su

California’s social and economic well-being is directly tied to financing for reliable, sustainable water. A new study from the Pacific Institute explores stable and sustainable sources of funding for water projects as a key to long-term solutions, and finds California’s increased dependence on general obligation (GO) bonds in funding water systems is unreliable and costly to both the state and taxpayers. Current water rates often do not fully cover the cost of providing water services and rarely reflect the full costs of the water itself, such as the ecosystem impacts related to extracting water. California ranks at the top of the EPA’s survey of infrastructure needs in terms of the investments required to maintain aging water systems over the next two decades. Climate change, continued population growth, and restoring critical ecosystems will add further to these costs. “Various financing options are used to invest in existing water systems and services, develop new ones, and mitigate environmental impacts, but there are serious economic and financial challenges,” said Dr. Newsha Ajami, lead author of the report. “The water sector needs a more comprehensive and stable financing portfolio.” According to the California Department of Water Resources, nominal annual debt service for outstanding general obligation water bonds in California has increased four-fold since 2000. This shift to greater use of bond funding can be linked to the decreased ability to raise government revenues through taxes and fees as a result of voter-approved initiatives like Proposition 13 and 218. General obligation bonds, however, are not a steady and reliable source of funding for long-term planning and decision-making because they require voter approval if they survive the legislative process, which is sensitive to economic ups and downs.

Bringing Water and Land Use Together

Local Government Commission | April 11th, 2019

In 2005, the California Legislature passed new laws that enable communities to join together to adopt Integrated Regional Water Management (IRWM) policies and practices.

In 2005, the California Legislature passed new laws that enable communities to join together to adopt Integrated Regional Water Management (IRWM) policies and practices. This comprehensive planning approach considers water resources in the context of an interconnected watershed with a network of regional governance, rather than as a combination of fragmented parts. Unfortunately, the IRWM program is dominated by the water sector and in most regions has not pursued alignment with land use. Similarly, the Sustainable Communities Strategies (SCS) mandated through SB 375 establish a framework for aligning land use practices (predominantly housing and transportation) across jurisdictions within a larger geographic region. Yet very few SCSs have taken water resources into account. While water management and land-use planning remain highly fragmented across the state, we are making progress toward a more integrated approach, especially when setting new state-level policies, regulations and guidance. The 2014 Sustainable Groundwater Management Act (SGMA) is a leap forward in this direction. For the first time, local land use agencies have an opportunity to be full partners with water agencies in shaping groundwater governance. It is too soon to determine how well these two sectors are integrating under SGMA, but early results are promising.

Building Drought Resilience in California’s Cities and Suburbs

Public Policy Institute of California (PPIC) | June 1st, 2017

Droughts are a recurring feature of California’s climate. Major droughts provide an opportunity to review management responses and derive policy lessons that can better

Droughts are a recurring feature of California’s climate. Major droughts provide an opportunity to review management responses and derive policy lessons that can better prepare society for the next one. Here we take stock of how California’s cities and suburbs have responded to recent droughts, review the state’s evolving role in urban drought management, and recommend actions to increase urban areas’ drought resilience. California’s urban water supply system is complex and highly decentralized, with 400-plus utilities serving more than 90 percent of the state’s residents. Following the hard lessons learned from the 1976–77 and 1987–92 droughts, these utilities made substantial investments in drought resilience. This included diversifying supplies with new surface and underground storage, interconnections with neighboring suppliers, recycled wastewater, and water transfer agreements, as well as freeing up supplies by reducing indoor water use. Consequently, urban water suppliers generally believed they were prepared as the state entered a five-year drought in 2012.

Bulletin 118: California's Groundwater Update 2020 (draft)

California Department of Water Resources (DWR) | March 1st, 2021

Groundwater is a precious and limited resource that is used in meeting the needs of California’s large and small urban areas, rural groundwater users, irrigated agricul

Groundwater is a precious and limited resource that is used in meeting the needs of California’s large and small urban areas, rural groundwater users, irrigated agriculture, and the environment. Since the last California’s Groundwater (CalGW) Update in 2003, there has been significant changes to land use, water use, water application practices, and water allocations. In addition, the effects of climate change have affected California’s reliance on groundwater. It is expected that there will be additional changes in land use, water use, adjustments in water allocations, and that climate change will continue to affect the environment, thus elevating the importance of the reporting in CalGW Updates.  According to the last comprehensive report, California’s Groundwater Update 2003 (CalGW Update 2003), California’s reliance on groundwater was approximately 30 percent during a wet-to-average precipitation water year and approximately 40 percent during dry periods. Since then, the percentage of groundwater reliance has increased to between 30 and 40 percent during above normal to-wet years and to as much as 58 percent during dry periods (California Department of Water Resources 2018).

Bulletin 16, Report of Sacramento-San Joaquin Water Supervision for 1949

California Department of Water Resources (DWR) | June 1st, 1950

Bulletin 39-I, South Coastal Basin Investigation, Records of Ground Water Levels at Wells for the Year 1940, Precipitation Records for the Season 1939-40

California Department of Water Resources (DWR) | July 1st, 1941