Topic: Desalination

Overview

Desalination

Recurrent droughts and uncertainties about future water supplies have led several California communities to look to saltwater for supplemental supplies through a process known as desalination.

Aquafornia news Berkeley Lab News Center

News release: New membrane technology could expand access to water for agricultural and industrial use

… A new technology equips membranes used in the reverse-osmosis desalination process with electrical conductivity, improving their ability to separate salts and other contaminants from hard-to-treat waters. Active Membranes, a California-based company, licensed the technology originating from UC Riverside and UCLA to advance its development and bring it to market. Their team received funding for this work from the National Alliance for Water Innovation (NAWI), a public-private partnership led by the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). NAWI focuses on advancing technologies that enable the use of unconventional water sources in real-world settings. In addition to federal support, NAWI is backed by several California water agencies, reflecting strong regional interest in securing reliable water supplies. According to NAWI Executive Director Peter Fiske, the new active membrane can effectively treat wastewater that is brought to the surface during oil and gas extraction. 

Other water reclamation and reuse news:

Aquafornia news Monterey County Now (Seaside, Calif.)

CPUC decision delay on Monterey water supply

Tomorrow, June 26, the California Public Utilities Commission was scheduled to adopt a proposed decision regarding the Monterey Peninsula’s current water supply and forecasted demand by 2050. And after already being rescheduled from the June 12 CPUC meeting by Commissioner Darcie Houck, who’s presiding over the matter, on June 24 Houck pulled it from the agenda again and rescheduled it until July 24, the CPUC’s next meeting. … The talking points discussed were a rehashing of Cal Am’s disagreement with the proposed decision, which projected a 2050 water demand of 13,732 acre-feet per year—the number Cal Am had been pushing for, and far higher than five outside estimates—and a current water supply of 11,204 acre-feet per year, which Cal Am thinks is too high. Cal Am officials also reiterated why they think the demand numbers are correct. Water demand on the Peninsula last year dipped below 9,000 acre-feet, the lowest level in decades, and the proposed decision presumes it will increase more than 4,500 acre-feet over the next 25 years. 

Aquafornia news Offshore Energy

Blog: Wave energy desalination pilot gets green light in Fort Bragg

Canadian Wave-powered desalination innovator Oneka Technologies has secured regulatory approval to move forward with its wave-powered desalination pilot project off the coast of Fort Bragg, California. According to Oneka Technologies, the Fort Bragg Planning Commission unanimously approved the initiative on May 28, 2025, following the completion of the environmental review process. The review included a 30-day public consultation. The project, partly funded by the California Department of Water Resources (DWR), is now entering the deployment phase. … This is said to be the first seawater desalination pilot to complete the CEQA process since California updated its regulations in 2015. The system is designed to produce freshwater using wave energy, operating off-grid and without greenhouse gas emissions.

Aquafornia news Monterey County Now

Opinion: How much water will we need by 2050?

… Having reported on water on the Monterey Peninsula for the better part of the last decade, it’s remarkable to reflect on what has transpired in that time: A political movement for public water, a political movement to stop Cal Am’s desal project in Marina, an innovative recycled water project and its expansion, and a conditional approval for Cal Am’s desal project, which is still being litigated on multiple fronts. … How much supply there is, and how much demand there will be by 2050, are among the things still being debated regarding Cal Am’s desal project (per a condition of approval from the California Coastal Commission). It was finally scheduled to be voted upon by the California Public Utilities Commission at a meeting in Sacramento tomorrow, June 12. Late yesterday, Commissioner Darcie Houck, who’s presiding over the proceeding, pulled it from tomorrow’s meeting and rescheduled it for June 26. … The whole purpose behind these efforts has been to lift the state’s cease-and-desist order that prohibits Cal Am from setting new water meters. But it’s the State Water Control Board that decides that.
–Written by Monterey County Now columnist David Schmalz.

Aquafornia news Arizona State University

News release: Squeezing every last drop out of wastewater

Industries that need ultra-pure water — including semiconductor, battery, pharmaceutical, food and beverage companies — are expanding in Arizona. One of the most overlooked challenges for these businesses is what gets left behind in the pursuit of clean water: brine, the salty byproduct of processes like reverse osmosis. For Shahnawaz Sinha, an associate research professor in civil and environmental engineering at Arizona State University, brine isn’t just waste, it’s an opportunity. Through a partnership with Nestlé and supported by ASU’s Arizona Water Innovation Initiative and the Global Center for Water Technology, Sinha is developing a mobile, closed-loop water recovery demonstration facility that could change how industries in the metro Phoenix area deal with brine. By recovering another 50%–90% of previously unusable water from industrial brine and reducing the remainder to solid salt, the project aims to minimize waste and extract freshwater to support Arizona’s economy and water resilience. 

Publication

Layperson’s Guide to Water Recycling
Updated 2024

Layperson's Guide to Water Recycling

Cities across California and the Southwest are significantly increasing and diversifying their use of recycled wastewater as traditional water supplies grow tighter.

The 5th edition of our Layperson’s Guide to Water Recycling covers the latest trends and statistics on water reuse as a strategic defense against prolonged drought and climate change.

Western Water California Water Map Gary Pitzer

Often Short of Water, California’s Southern Central Coast Builds Toward A Drought-Proof Supply
WESTERN WATER NOTEBOOK: Water agencies in Santa Barbara, San Luis Obispo counties look to seawater, recycled water to protect against water shortages

The spillway at Lake Cachuma in central Santa Barbara County. Drought in 2016 plunged its storage to about 8 percent of capacity.The southern part of California’s Central Coast from San Luis Obispo County to Ventura County, home to about 1.5 million people, is blessed with a pleasing Mediterranean climate and a picturesque terrain. Yet while its unique geography abounds in beauty, the area perpetually struggles with drought.

Indeed, while the rest of California breathed a sigh of relief with the return of wet weather after the severe drought of 2012–2016, places such as Santa Barbara still grappled with dry conditions.

Western Water Colorado River Basin Map Gary Pitzer

With Drought Plan in Place, Colorado River Stakeholders Face Even Tougher Talks Ahead On The River’s Future
WESTERN WATER IN-DEPTH: Talks are about to begin on a potentially sweeping agreement that could reimagine how the Colorado River is managed

Lake Mead, behind Hoover Dam, shows the effects of nearly two decades of drought. Even as stakeholders in the Colorado River Basin celebrate the recent completion of an unprecedented drought plan intended to stave off a crashing Lake Mead, there is little time to rest. An even larger hurdle lies ahead as they prepare to hammer out the next set of rules that could vastly reshape the river’s future.

Set to expire in 2026, the current guidelines for water deliveries and shortage sharing, launched in 2007 amid a multiyear drought, were designed to prevent disputes that could provoke conflict.

Western Water California Groundwater Map Layperson's Guide to Flood Management Gary Pitzer

Southern California Water Providers Think Local in Seeking to Expand Supplies
WESTERN WATER SIDEBAR: Los Angeles and San Diego among agencies pursuing more diverse water portfolio beyond imports

The Claude “Bud” Lewis Desalination Plant in Carlsbad last December marked 40 billion gallons of drinking water delivered to San Diego County during its first three years of operation. The desalination plant provides the county with more than 50 million gallons of water each day.Although Santa Monica may be the most aggressive Southern California water provider to wean itself from imported supplies, it is hardly the only one looking to remake its water portfolio.

In Los Angeles, a city of about 4 million people, efforts are underway to dramatically slash purchases of imported water while boosting the amount from recycling, stormwater capture, groundwater cleanup and conservation. Mayor Eric Garcetti in 2014 announced a plan to reduce the city’s purchase of imported water from Metropolitan Water District by one-half by 2025 and to provide one-half of the city’s supply from local sources by 2035. (The city considers its Eastern Sierra supplies as imported water.)

Central Coast Tour 2019
Field Trip - November 6-7

This 2-day, 1-night tour offered participants the opportunity to learn about water issues affecting California’s scenic Central Coast and efforts to solve some of the challenges of a region struggling to be sustainable with limited local supplies that have potential applications statewide.

Western Water Magazine

Tapping the Ocean: What is the Role of Desalination?
Winter 2016

This issue looks at the role of ocean desalination in meeting California’s water needs today and in the future.

Western Water Magazine

Tapping the World’s Largest Reservoir: Desalination
January/February 2003

This issue examines desalination and the role it could play in the future of water supply. In addition to an explanation of the basics of the technology, the article looks at costs, environmental impacts and groundwater application. Pilot desalination projects are featured, including a much-touted Carlsbad, Calif., facility that promises to substantially boost that region’s water supply.

Western Water Magazine

Desalination: A Drought Proof Supply?
July/August 2009

This printed issue of Western Water examines desalination – an issue that is marked by great optimism and controversy – and the expected role it might play as an alternative water supply strategy.

Western Water Magazine

Making the Connection: The Water/Energy Nexus
September/October 2010

This printed issue of Western Water looks at the energy requirements associated with water use and the means by which state and local agencies are working to increase their knowledge and improve the management of both resources.

Western Water Magazine

Viewing Water with a Wide Angle Lens: A Roundtable Discussion
January/February 2013

This printed issue of Western Water features a roundtable discussion with Anthony Saracino, a water resources consultant; Martha Davis, executive manager of policy development with the Inland Empire Utilities Agency and senior policy advisor to the Delta Stewardship Council; Stuart Leavenworth, editorial page editor of The Sacramento Bee and Ellen Hanak, co-director of research and senior fellow at the Public Policy Institute of California.

Video

A Climate of Change: Water Adaptation Strategies

This 25-minute documentary-style DVD, developed in partnership with the California Department of Water Resources, provides an excellent overview of climate change and how it is already affecting California. The DVD also explains what scientists anticipate in the future related to sea level rise and precipitation/runoff changes and explores the efforts that are underway to plan and adapt to climate.

Video

Salt of the Earth: Salinity in California’s Central Valley

Salt. In a small amount, it’s a gift from nature. But any doctor will tell you, if you take in too much salt, you’ll start to have health problems. The same negative effect is happening to land in the Central Valley. The problem scientists call “salinity” poses a growing threat to our food supply, our drinking water quality and our way of life. The problem of salt buildup and potential – but costly – solutions are highlighted in this 2008 public television documentary narrated by comedian Paul Rodriguez.

Video

Salt of the Earth: Salinity in California’s Central Valley (20-minute DVD)

A 20-minute version of the 2008 public television documentary Salt of the Earth: Salinity in California’s Central Valley. This DVD is ideal for showing at community forums and speaking engagements to help the public understand the complex issues surrounding the problem of salt build up in the Central Valley potential – but costly – solutions. Narrated by comedian Paul Rodriquez.

Video

Stormwater Management: Turning Runoff into a Resource

20-minute DVD that explains the problem with polluted stormwater, and steps that can be taken to help prevent such pollution and turn what is often viewed as a “nuisance” into a water resource through various activities.

Video

Drinking Water: Quenching the Public Thirst (60-minute DVD)

Many Californians don’t realize that when they turn on the faucet, the water that flows out could come from a source close to home or one hundreds of miles away. Most people take their water for granted; not thinking about the elaborate systems and testing that go into delivering clean, plentiful water to households throughout the state. Where drinking water comes from, how it’s treated, and what people can do to protect its quality are highlighted in this 2007 PBS documentary narrated by actress Wendie Malick. 

Video

Drinking Water: Quenching the Public Thirst (30-minute DVD)

A 30-minute version of the 2007 PBS documentary Drinking Water: Quenching the Public Thirst. This DVD is ideal for showing at community forums and speaking engagements to help the public understand the complex issues surrounding the elaborate systems and testing that go into delivering clean, plentiful water to households throughout the state.

Publication

Layperson’s Guide to Integrated Regional Water Management
Published 2013

The 24-page Layperson’s Guide to Integrated Regional Water Management (IRWM) is an in-depth, easy-to-understand publication that provides background information on the principles of IRWM, its funding history and how it differs from the traditional water management approach.

Aquapedia background

Sacramento-San Joaquin Delta and Salinity

The Sacramento-San Joaquin Delta always has been at the mercy of river flows and brackish tides.

Before human intervention, salty ocean water from the San Francisco Bay flooded the vast Delta marshes during dry summers when mountain runoff ebbed. Then, during winter, heavy runoff from the mountains repelled sea water intrusion.

Aquapedia background

Desalination

Charles E. Meyer Desalination Plant in Santa Barbara,  Calif.

Recurrent droughts and uncertainties about future water supplies have led several California communities to look to treat salty water for supplemental supplies through a process known as desalination.

Desalination removes salt and other dissolved minerals from water and is one method to reclaim water for other uses. This can occur with ocean water along the coast and in the interior at spots that draw from ancient salt water deep under the surface or where groundwater has been tainted by too much salt.

Western Water Excerpt Gary PitzerRita Schmidt Sudman

Desalination: A Drought Proof Supply?
July/August 2009

It seems not a matter of if but when seawater desalination will fulfill the promise of providing parts of California with a reliable, drought-proof source of water. With a con­tinuing drought and uncertain water deliveries, the state is in the grip of a full-on water crisis, and there are many people who see desalination as a way to provide some relief to areas struggling to maintain an adequate water supply.

Western Water Excerpt Gary PitzerRita Schmidt Sudman

Tapping the World’s Largest Reservoir: Desalination
Jan/Feb 2003

“Water, water, everywhere, nor any drop to drink.” – Samuel Taylor Coleridge
For time immemorial, the seas of the Earth have been seen as an enticing but unreachable source of fresh water. Separating the salt from ocean water was always a cost prohibitive process, primarily reserved to wealthy Middle Eastern nations and small-scale operations such as ocean-bound vessels and small islands. Otherwise, through the evolution of modern civilization, man has depended upon lakes, rivers and groundwater – a supply that comprises less than 3 percent of the planet’s total water.