The San Diego County Water Authority’s Board of Directors today unanimously approved a landmark agreement to explore an interstate water transfer and exchange pilot program with the U.S. Bureau of Reclamation, the Metropolitan Water District of Southern California, and agencies in Nevada and Arizona.,

The memorandum of understanding (MOU) – which still needs to be ratified by the other agencies – creates a pathway that could eventually allow the Water Authority to “move” water from the nation’s largest seawater desalination plant in Carlsbad to areas in the drought-ravaged Colorado River Basin that need more water. If successfully developed, this would create the first program to transfer water across state lines within the basin.

Such a program could help reduce water costs for working families in San Diego County by optimizing the region’s investments in reliability. Water purchases from the Claude “Bud” Lewis Carlsbad Desalination Plant would generate new revenues and offset costs for residents, improving regional water affordability.

“This agreement could be a gamechanger for San Diego County and the entire Southwest because it creates the possibility of a new, collaborative path for moving water where it’s needed most while keeping reliability and affordability at the center for ratepayers,” said Water Authority Board Chair Nick Serrano. “Leveraging existing resources like our Carlsbad desalination plant in this moment simply makes sense for everyone.”

Water transfers or exchanges would occur “on paper,” meaning agencies would access supplies through existing infrastructure and avoid costly new infrastructure.

The demand is clear: In recent years, agencies in Arizona and Nevada have sought ways to tap the Pacific Ocean, but the costs of construction are prohibitive. The Arizona Department of Water Resources, Central Arizona Water Conservation District and Southern Nevada Water Authority are part of the new MOU.

For more than 20 years, the seven states in the Colorado River Basin have wrestled with drought conditions that have created growing imbalances between water supplies and demands. As the Bureau of Reclamation, Basin States, Mexico, and tribal nations consider new operating guidelines for the river, new management strategies and interstate partnerships are increasingly critical.

Over roughly the same period, the Water Authority has invested $3 billion in water reliability efforts, including the Carlsbad plant, which produces up to 54 million gallons per day. Additionally, the 2003 Colorado River Quantification Settlement Agreement – which generates conserved water in the Imperial Valley – and hard-wired conservation in the San Diego region have positioned the Water Authority to not only meet the region’s needs but also provide relief to other areas.

“Next-generation strategies must include interstate partnerships that deliver water where it’s needed most,” said Water Authority General Manager Dan Denham. “We appreciate the collaboration with the Bureau of Reclamation, Metropolitan Water District, Arizona and Nevada. New ideas are challenging to implement, but it’s in everyone’s best interest to make this work.”

The San Diego County Water Authority and Eastern Municipal Water District have reached a new long‑term water supply agreement – the second major regional partnership announced by the Water Authority in 2026. This latest arrangement expands a growing effort among Southern California water agencies to coordinate resources, strengthen drought preparedness, and make more efficient use of existing water supplies.

The Water Authority and EMWD collectively support more than 4 million residents in San Diego and Riverside counties. Leaders from both agencies said regional cooperation is essential as climate variability and economic pressures reshape long‑term planning and underscore the need for fresh approaches that sustain water affordability and reliability.

“When I became Chair, I committed to bring new, innovative solutions to the table to match the moment we’re in with ratepayer affordability as our North Star,” said Water Authority Board Chair Nick Serrano. “This partnership is exactly that: practical and common-sense regional cooperation that strengthens reliability and creates real value for ratepayers.”

Under the new partnership, EMWD will ramp up to receiving 10,000 acre‑feet of water each year for the next 21 years. EMWD is also securing an advance of roughly 30,000 acre‑feet for later delivery – a strategic tool that gives the district greater flexibility during dry periods and reduces long‑term supply risks.

For the Water Authority, the agreement will generate an estimated $74 million over the first five years, including upfront payments. These funds will help minimize wholesale water rate pressures while ensuring the region continues benefiting from decades of investment in supply diversification.

The Water Authority’s current draft Urban Water Management Plan confirms that the agency’s diversified portfolio of water supplies, combined with a sustained commitment to water-use efficiency, will meet the region’s water needs at least through 2050, even during multiple dry years. That means the Water Authority can continue providing reliable water for San Diego County while making the most of long-term investments through agreements like the one with EMWD.

“Affordability and reliability go hand‑in‑hand,” said Water Authority General Manager Dan Denham. “This new agreement shows that when agencies share resources and expertise, we can deliver greater value for our customers. EMWD has been an exceptional partner in advancing a more resilient and innovative water future.”

EMWD and the Water Authority worked collaboratively to develop the agreement, reflecting a shared commitment to the health and resilience of Southern California’s water system. EMWD leaders said the new supply arrangement supports long‑term planning for one of California’s fastest‑growing service areas. The district gains access to dependable supplies without the expense or timelines associated with constructing new major infrastructure.

“Regional cooperation is essential for a stable water future,” said EMWD Board President Stephen J. Corona. “This agreement highlights how collaboration can generate benefits well beyond our service boundaries.”

“Dan Denham and I have been discussing a vision for our collective water future for many years,” said EMWD General Manager Joe Mouawad. “This agreement is the first step of many towards effective regional collaboration, which is key to positive outcomes for EMWD customers as well as those in San Diego, and around Southern California.”

Like the March agreement between the Water Authority and Western Municipal Water District, water deliveries for EMWD will move through existing facilities operated by the Metropolitan Water District of Southern California, meaning water will be conveyed using current pipelines and treatment systems. This approach avoids the need for new construction and enables the transfer to be implemented quickly and efficiently.

“When Metropolitan and the Water Authority settled their long-running legal dispute last year, it opened up a new era of collaboration, making possible agreements like this one,” said Metropolitan board Vice Chair Michael Camacho. “By working together and thinking beyond our own political boundaries, we can forge smart solutions to ensure all Southern California communities have reliable water despite the ongoing challenge of climate change.”

The water transfer partnerships are part of a broader effort to modernize water management across the Southwest and Southern California. In addition, the Water Authority has committed to developing a pilot program that could result in transferring locally produced desalinated seawater to Colorado River Basin partners in other states – another step toward a more flexible and interconnected regional water network.

The San Diego County Water Authority and Western Municipal Water District today announced a historic long-term regional water supply agreement that strengthens water reliability and creates a paradigm shift in how water providers share resources across the region to benefit millions of customers.

Together, the agencies serve communities representing more than 4 million Southern California residents across Riverside and San Diego counties.

“This agreement is a win for San Diego ratepayers, a win for Western, and a win for Southern California,” said Water Authority Board Chair Nick Serrano. “It allows us to maximize the value of the investments San Diego County residents made over decades, strengthen water reliability, and do so in a way that is mindful of affordability and public responsibility. It is exactly the kind of innovative, collaborative approach this moment demands.”

Under the agreement, Western Water will receive a minimum of 10,000 acre-feet of water annually over the next 21 years, enough to supply approximately 30,000 Southern California households each year and strengthen long-term water reliability for the communities it serves. Western Water is also pre-purchasing approximately 30,000 acre-feet of water for future delivery, a nearly $40 million investment that provides added flexibility during drought.

The partnership will generate approximately $13.5 million annually in revenue for the San Diego County Water Authority, with the agreement expected to deliver roughly $100 million over the first five years after accounting for the upfront payments. Those revenues help offset the cost of long-term water supply investments while making efficient use of existing regional water supplies.

The Water Authority’s current draft Urban Water Management Plan confirms that the agency’s diversified portfolio of water supplies, combined with a sustained commitment to water-use efficiency, will meet the region’s water needs through 2050, even during multiple dry years. That means the Water Authority can continue providing reliable water for San Diego County while making the most of long‑term investments through agreements like the one with Western Water.

Revenues generated through those agreements help reduce wholesale water rate pressures for San Diego County customers.
“The county’s ratepayers continue to benefit from investments in water conservation that give us flexibility to balance water affordability and reliability,” said Water Authority General Manager Dan Denham. “This agreement would not have been possible without the incredible team at Western Water that shares our commitment to visionary leadership and collaboration in developing a new way to think about water resources.”
For Western Water, the partnership strengthens long-term water supply planning by securing access to highly reliable supplies at one of the most cost-effective opportunities available today.

Western Water serves nearly one million residents across southwest Riverside County, one of California’s fastest-growing regions, where planning ahead for dependable water supplies is essential for community stability and economic growth. By securing access to these supplies, Western Water strengthens drought protection and long-term supply planning without the cost, risk, or timelines associated with developing major new water supply projects.

“Partnerships like this show what is possible when water agencies work together,” said Laura Roughton, president of Western Water’s Board of Directors. “By sharing secured resources, we can strengthen water reliability for our communities while freeing up supplies that are needed elsewhere across the region. It’s a win for our customers, a win for San Diego, and a win for Southern California’s water system.”
Western Water and the Water Authority worked collaboratively to develop the agreement, reflecting a shared commitment to the health and resilience of Southern California’s water system for generations.

“With California’s water landscape shifting due to climate variability, economic and population growth, now is the time to pursue innovative partnerships that strengthen long-term water planning and affordability,” said Craig Miller, general manager of Western Water. “We appreciate the leadership and professionalism of the San Diego County Water Authority in helping make this partnership possible.”

The agreement builds on a series of innovative efforts by the Water Authority to make the most of its long-term water supply investments. Earlier this year, the Water Authority’s Board approved an agreement with the U.S. Bureau of Reclamation to explore a pilot program that could allow desalinated seawater to be exchanged with Colorado River Basin states – another step aimed at strengthening water security across the Southwest while modernizing how regional water resources are managed.

Water purchased by Western Water will be delivered through existing connections within the Metropolitan Water District of Southern California’s regional pipeline system, meaning no new infrastructure is required. Because the water moves through existing facilities, transfers can be carried out efficiently without building new pipelines or treatment plants.

“Southern California is an economic engine for the nation, and its future depends on a secure and sustainable water supply,” said Metropolitan Board Chair Adán Ortega, Jr. “This agreement was made possible by a legal settlement forged last year between Metropolitan and the Water Authority. That settlement gave birth to a new business model allowing the movement of water between our 26 member agencies. The water that is part of this agreement didn’t just fall from the sky. It was conserved by businesses and residents for the benefit of greater Southern California. Together, we are ensuring our region continues to thrive for generations to come and providing a model that can solve other water challenges in the Southwest.”

The San Diego County Water Authority today released its draft 2025 Urban Water Management Plan (UWMP) and draft Water Shortage Contingency Plan (WSCP) for public review. The draft UWMP confirms that the Water Authority’s diversified portfolio of water supplies, combined with a sustained commitment to water-use efficiency, will meet the region’s water supply needs through 2050, even during multiple dry years.  

As a result, the Water Authority is pursuing water transfer agreements with agencies outside of the San Diego region. Those agreements would provide the Water Authority with revenue to help mitigate future wholesale water rate increases.   

The draft documents will be available for a 45-day public comment period ending April 25, 2026. The Water Planning and Environmental Committee of the Water Authority’s Board of Directors will hold a public hearing on April 23, 2026. The Board is expected to consider adoption of the final plans at its meeting on May 28. The draft plans must be submitted to the state by July 1. 

To read the draft documents, or to submit comments, go to: www.sdcwa.org/water-authority-releases-water-planning-documents-for-public-review-and-comment/.

“Thanks to the Water Authority’s water supply investments, San Diego County is well positioned to meet future water demands with reliable supplies. We are continuing to work with partners across Southern California and the Southwest to support supply reliability, while maintaining the water supply that San Diego County residents and businesses depend on,” said Water Authority Director of Water Resources Jeff Stephenson. 

The Water Authority started the process to prepare the plans in 2024, coordinating closely with its 22 member agencies, which provided input for the draft plans.  

The draft UWMP’s long-range demand forecast shows that regional water demands are expected to remain nearly flat through 2050. This is consistent with the forecasts prepared by the Water Authority’s member agencies and the Metropolitan Water District of Southern California. 

Multiple supply and demand projections factor into the draft UWMP, which is mandated by the state to ensure sufficient supplies over a 25-year planning horizon. The draft UWMP is not used to set water rates; rates are set annually based on multiple financial factors at the time, not long-term projections about water supplies. 

The content of the draft UWMP is driven by statutory guidelines and input from the Water Authority’s Board of Directors. The plan accounts for changes in socio-economic factors, such as the number of projected housing units, the mix of single-family and multi-family dwellings, and employment growth. The plan also supports state laws that link approval for large housing developments to water supply availability.  

In addition to the UWMP and WSCP, the Water Authority also regularly updates its Water Facilities Master Plan, which focuses on the infrastructure necessary to meet projected long-term demands, and its Long-Range Financing Plan. Those documents work together to ensure the right mix of supplies and facilities to meet the region’s water needs in a sustainable way. 

The San Diego County Water Authority Board of Directors on Thursday unanimously elected Carlsbad City Councilmember Teresa Acosta as the Board’s new secretary. Acosta replaces Joy Lyndes, who stepped down following her recent announcement that she will not seek re-election to her position on the Encinitas City Council this year.

“The San Diego County Water Authority is fortunate to have Director Acosta step up during this critical time in the agency’s history,” said Board Chair Nick Serrano, who represents the City of San Diego. “As an elected official in our North County, she brings a community perspective and a collaborative mindset to the Authority. She also shares my unwavering commitment to ensuring ratepayer affordability, and I look forward to working with her in this new leadership role to bring down costs for all San Diegans while ensuring a safe and reliable water supply.”

Acosta, who has been Carlsbad’s District 4 councilmember since 2020, currently serves as vice chair of the Water Authority’s Legislation and Public Outreach Committee and is a member of the Administrative and Finance Committee. Additionally, Acosta is the First Vice President of the League of California Cities Board of Directors and will become its president in September 2026.

“I’m honored by the support of my colleagues as I take over the role of Board secretary,” said Director Acosta. “I look to expand on the foundation that Director Lyndes and the rest of the leadership team built as we ensure this agency is doing everything possible for working families across the region.”

Director Lyndes has represented San Dieguito Water District on the Water Authority Board since 2023 and has served as secretary since her unanimous election in October 2024. She plans to remain on the Water Authority Board through the end of the year.

“Director Lyndes has brought grounded, thoughtful, and collaborative leadership to every Board meeting, particularly as we have placed significant focus on affordability, reliability, and long-term planning,” Chair Serrano said. “I am sincerely grateful for her leadership here at the Water Authority and her continued service to our region.”

The San Diego County Water Authority Board of Directors today voted unanimously to renew the Permanent Special Agriculture Water Rate (PSAWR) Program, ensuring discounted water remains available to the region’s farmers in the coming years.

The extension of the program, which began in its current form in 2020, was backed by the San Diego County Farm Bureau. San Diego County is home to more farms than any county in the nation, making the discount water rates program vital to the continued success of the local agricultural sector. More than 1,000 farmers across 11 retail water agencies are enrolled in the program.   

“The Water Authority has worked closely with San Diego’s ag community to sustain a program that is valuable to farmers while also benefitting the entire region,” said Water Authority General Manager Dan Denham. “This is a win for our region’s economy and residents, supporting jobs and a way of life that is part of San Diego County’s identity.” 

PSAWR was designed to provide qualified agricultural customers the benefit of discounted water in exchange for an interruptible, lower level of service during times of water supply shortages or emergencies. The program is valuable to non-farm customers because it helps maintain water sales and spreads fixed costs over larger volumes of water that otherwise would be paid by non-farm customers.  

PSAWR rates were already in place for 2026. Today’s action by the Water Authority Board creates a framework for extending the program in 2027.  

“The Authority has long been – and clearly remains – a dedicated supporter of the region’s 5,000 farms and farmers,” San Diego County Farm Bureau President Jimmy Ukegawa said in a Nov. 4 letter to Water Authority Board Chair Nick Serrano urging the renewal of the ag rate program. “The Farm Bureau sincerely appreciates the time, effort, and thoughtful attention the Board and staff have devoted to this critical issue.” 

San Diego County Water Authority General Manager Dan Denham today issued a statement on multi-state negotiations to set operating guidelines for the Colorado River:

“We are cautiously optimistic that consensus on the Post-2026 Guidelines remains possible. In the coming weeks, we will stay engaged in the process to ensure that any agreement fairly represents the San Diego region and other water users. Looking ahead, the Colorado River will continue to face challenges, but thanks to our region’s investments in climate resiliency, we are well-positioned to meet our water needs. We will continue to work with other states and California parties to protect our long-term investments while pursuing innovative solutions like transferring desalinated seawater to where it is needed most.”