Sean Bressie

New Water Affiliates Group Forms at Scripps’ Center for Western Weather and Water Extremes

A new membership program at Scripps Institution of Oceanography leverages the latest atmospheric river science to optimize water resource management

Atmospheric river storms cause 40-60 percent of annual precipitation and roughly 85-99 percent of flood damages on the West Coast. With atmospheric rivers vital to water supply and the main drivers of flooding, the Center for Western Weather and Water Extremes (CW3E) at Scripps Institution of Oceanography at UC San Diego this month has formed the Water Affiliates Group (WAG), a new annual membership program that brings together water agencies and other water resource stakeholders to share best practices in forecast informed reservoir operations,  better understand atmospheric river storms and drought, and strategize ways to improve water management that mitigate flood risk and increase water supply reliability. 

Many winter water operations in the West are strictly regulated by U.S. Army Corps of Engineers-issued water control manuals based on historical long-term averages of winter storms and spring runoff. A few reservoir operators in the region have used weather forecasts in operations. These manuals have traditionally operated on seasonal, once approved by the U.S. Army Corps, directives to lower reservoir levels in October to make room to prevent winter storm runoff floods and raise levels in April, if it rains. A new federal policy now allows water managers to incorporate forecasted conditions in planning water operations and in updates to water control manuals, allowing operators to leverage advances in weather and water forecasting to better adapt to anticipated drought or storm conditions. 

CW3E is a leader in Forecast Informed Reservoir Operations (FIRO), which uses data from watershed monitoring and modern weather and water forecasting to help water managers determine the best course of action for retaining or releasing water from reservoirs depending upon the forecasted conditions. There are on-going FIRO projects at Russian River Basin (Lake Mendocino), the Santa Ana River Basin (Prado Dam), and the Yuba-Feather River Basins (New Bullards Bar and Oroville). As forecasting skill improves, and with more frequent and greater extremes in floods and droughts likely in the future climate, FIRO is aiding reservoir operators in developing procedures for leveraging improved forecasts within established guidelines. 

“The vision for the new Water Affiliates Group is to develop a strong network of like-minded water leaders to strategize and execute plans for research and applications developments that support best practices in forecast-informed water operations, and pioneer innovative solutions in water supply management that ultimately preserves public safety and saves money for ratepayers, ”said F. Martin (Marty) Ralph, director of the Center for Western Weather and Water Extremes at Scripps and a leading researcher studying atmospheric rivers.  

There are 11 founding partners of the Water Affiliates Group: Irvine Ranch Water DistrictOrange County Water DistrictSan Bernardino Valley Municipal Water District, San Diego County Water AuthoritySan Francisco Public Utilities Commission, Sonoma WaterTurlock Irrigation District, Yuba Water Agency, East Bay Municipal Utility District, Santa Clara Valley Water District, Fresno Metropolitan Flood Control District and Salt River Project. Members of the Water Affiliates Group have the opportunity to share their perspectives with CW3E scientists and other water districts at the annual workshops and conferences that the Center convenes. 

CW3E has numerous tools and technologies that members of the Water Affiliates Group can use to augment water research and methods of implementation. These tools include research on water supply reliability, flood management, greenhouse gas mitigation, groundwater recharge, public safety, observations, forecasting, decision support, climate outlooks (months- to decades-long), and hazard assessment. 

To learn more about the CW3E Water Affiliates Group,  visit the CW3E websiteand contact Gwen Nero, Director of Corporate Affiliates, Business Development, Industry Outreach, and Innovation at Scripps Institution of Oceanography at  


Commentary from founding partners on the new Water Affiliates Group:

“Ensuring water supply reliability is incredibly important for today’s water leaders.  The Water Affiliates Group has been formed at the right time and will help shepherd in a new level of industry networking and top-notch research that will support successful water operations throughout the state.” - Steven E. LaMar, Board of Directors, Irvine Ranch Water District


“We value our partnership with the Water Affiliates Group because it is a testament to true collaboration. Water and government agencies and leading researchers have come together to enhance water management to make California more resilient during times of drought,” stated Orange County Water District President Vicente Sarmiento.  “As part of this effort, the Orange County Water District is studying the feasibility of increasing water capture behind Prado Dam which would allow us to capture and use an additional 20,000 acre-feet, or 6.5 billion gallons, of stormwater in a wet year. This creates a new local water supply that is enough for 160,000 people―a tremendous benefit to our region that makes us less reliant on costly imported supplies.”


“Joining the Water Affiliates Group is a natural fit for Valley District, with our history of science-based decision making and proactive project development," stated T. Milford Harrison, Board President for the San Bernardino Valley Municipal Water District. "We anticipate collaborating with the CW3E to assess both risks and opportunities for our various groundwater recharge projects and foresee eventually incorporating their Forecast-Informed Reservoir Operations (FIRO) modeling into our water resource planning."


“This partnership with Scripps Institution of Oceanography underscores our commitment to strategic, science-based decision-making and long-term planning. By supporting advances in forecasting, we can more efficiently and effectively manage water resources both locally and statewide. This ultimately will benefit everyone in California by helping sustain our economy and quality of life.” -- Jim Madaffer, Board Chair, San Diego County Water Authority


"The San Francisco Public Utilities Commission is pleased to be founding members of the Water Affiliates Group, supporting the development of models and data products that will advance the understanding of the complex weather patterns experienced in California," said Steve Ritchie, Assistant General Manager for the San Francisco Public Utilities Commission. "Innovative modeling and measurement methods are critical to understanding current and future weather patterns. The SFPUC’s partnership with the Water Affiliates Group is an important step forward in developing and implementing these tools for water managers throughout California.


“Sonoma Water has worked with CW3E since its inception to brainstorm, create and implement successful state of the art water management tools, many that are being replicated across California. In the era of climate change, adaptation is mission critical.  Our partnership with CW3E as a founding member exemplifies the trust and ongoing support needed to meet these challenges together,” said Grant Davis, general manager, Sonoma Water.


“Turlock Irrigation District has been utilizing Scripps’ atmospheric river data to inform our reservoir operations for the last few years. Using this data has proven invaluable to our operations, improves public safety, and provides tremendous value to our customers,” said Turlock Irrigation District General Manager Michelle Reimers. “We are thrilled to be founding members of the Water Affiliates Group, and are excited to enhance our relationship with Scripps and continue using the latest technology to inform our water operations.”


“Our partnership with Scripps has been extremely productive and beneficial,” said John James, Yuba-Feather FIRO co-chair and Water Project Manager for Yuba Water Agency. “As a member of the new Water Affiliates Group, it’s exciting to continue to grow Scripps involvement with the Agency and leverage the remarkable research they provide for the benefit of both the people of Yuba county and the state.”


"The East Bay Municipal Utility District places great value on advanced scientific research. As we head into our second century of service on behalf of 1.4 million people in the San Francisco East Bay Area, the concepts and policies discussed by the Water Affiliates Group will inform our long-range plans to address the challenges that will come with climate change and extreme weather events. We hope to contribute and learn much from our participation in theWater Affiliates Group," said Marguerite Young, district board president of East Bay Municipal Utility District.


"The CW3E at Scripps leads to a variety of contemporary, science-based Atmospheric River and FIRO programs and projects to optimize weather, climate and water forecasts," said Lisa Bankosh, Acting Deputy Operating Officer of the Watersheds Stewardship and Planning Division at Santa Clara Valley Water District. "Valley Water has elected to join and be a founding member of the CW3E. This membership will provide Valley Water with the opportunity to help guide and provide feedback on strategies to transfer research to operations through scientific insights and decision support tools."


"The District is exploring re-operation of its Redbank and Fancher Creek flood control project, to augment regional water supplies through increased groundwater recharge. Working with CW3E will give the district access to the experience and advice of its members, which include agencies studying Forecast-Informed Reservoir Operations in northern and southern California. " -- Peter Sanchez, Interim General Manager at Fresno Metropolitan Flood Control District


“Joining the CW3E Water Affiliates Group provides SRP a unique opportunity to continue the enhancement of short-term and long-term planning, ensuring an affordable and reliable water supply to its shareholders and sustaining life and economic viability in the Phoenix area," said Dave Roberts, Associate General Manager of Water Resources of Salt River Project. "As a regionally influential water supplier, SRP views science-based decision making as the key for capitalizing on opportunities to improve regional water supply resiliency and sustainability.”

** This press release was updated on September 30, 2020 to add San Bernadino Valley Municipal Water District and San Francisco Public Utilities Commission as Founding Members. 


** This press release was updated on December 15, 2020 to add East Bay Municipal Utility District, Santa Clara Valley Water District and Fresno Metropolitan Flood Control District as Founding Members.


**This press release was updated on January 26, 2021 to add Salt River Project as a Founding Member.



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