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California Desalination Planning Handbook
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California Desalination Planning Handbook
Department of Water Resources | March 4, 2008...
Summary
In September 2002, AB 2717 was signed into law, designating the Department of Water Resources (DWR) to establish the California Desalination Task Force...
In September 2002, AB 2717 was signed into law, designating the Department of Water Resources (DWR) to establish the California Desalination Task Force (Task Force) to “make recommendations related to potential opportunities for the use of seawater and brackish water desalination.” The Task Force, through DWR, was to report to the legislature on potential opportunities for the use of seawater and brackish water desalination in California, impediments to the use of desalination technology; and what role, if any, the State should play in furthering the use of desalination technology.

This Handbook builds on the report from the Task Force, which includes a list of key findings and major recommendations, submitted to the State Legislature in early 2004. (Chapter 9, #1 contains a link to the Task Force findings and recommendations.)

The Task Force was comprised of a broad array of stakeholders who worked to develop consensus on the many recommendations developed. While consensus was not achieved on all points, the findings and recommendations highlighted were broadly supported by Task Force members.

No claims of consensus are made for this Handbook. But every effort was made to build as closely as possible on the Task Force recommendations and to accurately describe both the opportunities and concerns associated with desalination. Furthermore, the Handbook is intended to outline a process to assist in: 1) determining the appropriate conditions, 2) addressing identified concerns, and 3) building public trust for desalination projects.

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Desalination – Brackish and Sea Water (Resource Management Strategy)
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Desalination – Brackish and Sea Water (Resource Management Strategy)
Department of Water Resources | July 29, 2016...
Summary
Desalination, the removal of salts from saline waters, is one of the few options available to augment California’s water supply. California has facilities...
Desalination, the removal of salts from saline waters, is one of the few options available to augment California’s water supply. California has facilities that desalinate sea water for coastal communities and brackish groundwater for inland water users — many of which have provided high-quality water to their customers for more than 10 years. As water supplies in California become more constrained, many water suppliers with nearby saline water sources are evaluating desalination as a way to provide reliable supply in response to uncertainties relating to future drought and climate change.

While desalination is not a viable method for many water suppliers in the state, some not yet engaged in the process could realize significant supply and reliability benefits — even though desalination of both sea water and brackish groundwater comes with financial and environmental challenges. For water suppliers with desalination opportunities, how they implement environmentally sustainable projects is a key issue facing multiple California communities.

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Desalination and Membrane Technologies: Federal Research and Adoption Issues
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Desalination and Membrane Technologies: Federal Research and Adoption Issues
Congressional Research Service | January 2, 2015...
Summary
In the United States, desalination and membrane technologies are used to augment municipal water supply, produce high-quality industrial water supplies, and reclaim contaminated...
In the United States, desalination and membrane technologies are used to augment municipal water supply, produce high-quality industrial water supplies, and reclaim contaminated supplies (including from oil and gas development). Approximately 2,000 desalination facilities larger than 0.3 million gallons per day (MGD) operate in the United States; this represents more than 2% of U.S. municipal and industrial freshwater use.

At issue for Congress is what should be the federal role in supporting desalination and membrane technology research and facilities. Desalination issues before the 114th Congress may include how to focus federal research, at what level to support desalination research and projects, and how to provide a regulatory context that protects the environment and public health without disadvantaging desalination’s adoption.

Construction of desalination facilities, like many other types of projects, often requires a significant number of local, state, and federal approvals and permits. Emerging technologies (e.g., forward osmosis, capacitive deionization, and chlorine resistant membranes) show promise for reducing desalination costs. Research to support emerging technologies and to reduce desalination’s environmental and human health impacts is particularly relevant to future adoptions of desalination and membrane technologies.

The federal government generally has been involved primarily in desalination research and development (including for military applications), some demonstration projects, and select full-scale facilities. For the most part, local governments, sometimes with state-level involvement, are responsible for planning, testing, building, and operating desalination facilities. Some states, universities, and private entities also undertake and support desalination research.

While interest in desalination persists among some Members, especially in response to drought concerns, efforts to maintain or expand federal activities and investment are challenged by the domestic fiscal climate and differing views on federal roles and priorities.

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Desalination Plant Entrainment Impacts and Mitigation
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Desalination Plant Entrainment Impacts and Mitigation
California State Water Resources Control Board | October 9, 2013...
Summary
Raw seawater is used for a variety of purposes, including as source water for desalination plants and to cool coastal power plants. Raw...
Raw seawater is used for a variety of purposes, including as source water for desalination plants and to cool coastal power plants. Raw seawater is, however, not just cold and salty but an ecosystem that contains diverse and abundant organisms including the young stages of numerous invertebrates and fishes. Whether impinged (large individuals stuck on screens prior to entering the plant or killed during other plant processes such as heat treatment) or entrained (small individuals carried into the plant with the water) the organisms are killed, essentially eliminating the living production in the water used (review in York and Foster 2005). Considerable research has have been done in California to better estimate losses to this ecosystem by coastal power plant intakes (York and Foster 2005, Steinbeck et al. 2007), and to determine how these losses can be mitigated (Strange et al. 2004). The information from this research has contributed to State of California policy regulating water used by power plants.

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Desalination, With a Grain of Salt – A California Perspective
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Desalination, With a Grain of Salt – A California Perspective
Pacific Institute | June 1, 2006...
Summary
In Desalination, With a Grain of Salt – A California Perspective, the Pacific Institute provides a comprehensive overview of the history, benefits, and...
In Desalination, With a Grain of Salt – A California Perspective, the Pacific Institute provides a comprehensive overview of the history, benefits, and risks of ocean desalination, and the barriers that hinder more widespread use of this technology, especially in the context of recent proposals for a massive increase in desalination development in California.Long considered the Holy Grail of water supply, desalination offers the potential of an unlimited source of fresh water purified from the vast oceans of salt water that surround us. The public, politicians, and water managers continue to hope that cost-effective and environmentally safe ocean desalination will come to the rescue of water-short regions. While seawater desalination plants are already vital for economic development in many arid and water-short areas of the world, many plants are overly expensive, inaccurately promoted, poorly designed, inappropriately sited, and ultimately useless. To avoid new, expensive errors, policymakers and the public need to take a careful look at the advantages and disadvantages of desalination and develop clear guidance on how to evaluate and judge proposals for new facilities.

The potential benefits of ocean desalination are great, but the economic, cultural, and environmental costs of wide commercialization remain high. In many parts of the world, alternatives can provide the same freshwater benefits of ocean desalination at far lower economic and environmental costs. These alternatives include treating low-quality local water sources, encouraging regional water transfers, improving conservation and efficiency, accelerating wastewater recycling and reuse, and implementing smart land-use planning.

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High-Salinity Sensitivity Study: Short-and Long-Term Exposure Assessments
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High-Salinity Sensitivity Study: Short-and Long-Term Exposure Assessments
State Water Resources Control Board | April 12, 2013...
Summary
The West Basin Municipal Water District (WBMWD) High Salinity Sensitivity Study (HSS Study) comprehensively evaluated the potential short-term and long-term exposure effects of...
The West Basin Municipal Water District (WBMWD) High Salinity Sensitivity Study (HSS Study) comprehensively evaluated the potential short-term and long-term exposure effects of high salinity discharges from the WBMWD ocean water desalination demonstration facility (OWDDF) on aquatic organisms representative of communities indigenous to various near shore environments in Southern California.

Short-term effects were evaluated using Whole Effluent Toxicity (WET) bioassays developed by the U.S. Environmental Protection Agency (USEPA) to quantify the magnitude and threshold of potential biological effects of discharges (e.g. treated wastewater). Both acute toxicity (mortality effects) and chronic toxicity (mortality + sublethal effects) bioassays were performed by a state accredited bioassay laboratory. Long-term effects were evaluated using mesocosm procedures performed at the OWDDF by exposing multiple organisms for eight weeks to ambient seawater and diluted brine flows from the OWDDF in large aquaria constructed to simulate the OWDDF discharge environment.

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Hyper-Salinity Toxicity Thresholds for Nine California Ocean Plan Toxicity Test Protocols
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Hyper-Salinity Toxicity Thresholds for Nine California Ocean Plan Toxicity Test Protocols
State Water Resources Control Board | July 1, 2012...
Summary
A growing number of coastal cities in California are exploring the potential for ocean desalination as a means to augment freshwater supplies. There...
A growing number of coastal cities in California are exploring the potential for ocean desalination as a means to augment freshwater supplies. There are currently a number of desalination facilities proposed or operating in California. The process of desalination most commonly utilizes reverse osmosis (RO) to remove salts from groundwater, reclaimed water, and seawater. This process results in production of hypersaline reject brine. This reject brine may be discharged into the marine environment, sometimes in combination with discharge from a sewage treatment plant or power plant effluent. Typical RO reject brine produced using 100% seawater can have approximately twice the original salt content of seawater.

In order to ensure that brine discharges do not pose risk to coastal receiving waters, it is anticipated that desalination plants will be required to monitor effluent toxicity. Monitoring requirements will likely include testing for effluent toxicity using some combination of the short-term chronic toxicity test protocols listed in the 2009 California Ocean Plan (SWRCB, 2009).

While the tests listed in the Ocean Plan have been the subject of ongoing research, no comprehensive studies of the effects of hyper-salinity have been conducted with all seven toxicity test organisms (nine protocols when including sand dollar and urchin fertilization endpoints). The results from these tests will allow determination of the toxicity of hypersaline brine in the absence of any additional toxic constituents that may be produced during the desalination process. These results provide resource managers with background information to facilitate interpretation of toxicity test results from desalination plant effluent testing and permitting of desalination facilities. The results will also be used in the development of an amendment to the California Ocean Plan that addresses impacts to marine life from intakes and discharges from desalination facilities.

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Key Issues in Seawater Desalination in California: Costs and Financing
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Key Issues in Seawater Desalination in California: Costs and Financing
Pacific Institute | November 27, 2012...
Summary
Economics – including both the cost of the water produced and the complex financial arrangements needed to develop a project – are key...
Economics – including both the cost of the water produced and the complex financial arrangements needed to develop a project – are key factors that will determine the ultimate success and extent of desalination in California. New research from the Pacific Institute, Key Issues for Seawater Desalination in California: Cost and Financing, assesses desalination costs, financing, and risks associated with desalination projects. The Pacific Institute analysis finds that the cost to produce water from a desalination plant is high but subject to significant variability, with recent estimates for plants proposed in the state ranging from $1,900 to more than $3,000 per acre-foot.

“Seawater desalination remains among the most expensive water-supply options available, although the public and decision-makers must exercise caution when comparing costs among different projects,” said Heather Cooley, co-director of the Pacific Institute Water Program and lead author of the report. “In some cases, costs are reported in ways that are not directly comparable. For example, some report the cost of the desalination plant alone, while others include the cost for additional infrastructure needed to integrate the desalination plant into the rest of the water system. Some estimates include costs to finance the project, while others don’t. Even when there is an apples-to-apples comparison, there are a number of site- and project-specific factors that make cost comparisons difficult, such as energy, land, and labor costs and the availability of visible and hidden subsidies.”

Key Issues for Seawater Desalination in California: Cost and Financing is part of a series of research reports in progress that identify key outstanding issues that must be addressed before additional proposals for new seawater desalination in California are approved. Other issues addressed include the environmental impacts of seawater desalination, the cost and financing of proposed projects, and energy requirements and their greenhouse gas implications.

Our analyses seek to provide communities and decision makers with information needed to make decisions about building desalination plants and to create a more rational and sustainable policy around seawater desalination along the California coast, and elsewhere.

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Key Issues in Seawater Desalination in California: Energy and Greenhouse Gas Emissions
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Key Issues in Seawater Desalination in California: Energy and Greenhouse Gas Emissions
Pacific Institute | May 1, 2013...
Summary
Interest in seawater desalination in California is high, with 17 plants proposed along the California coast and two in Mexico. But removing the...
Interest in seawater desalination in California is high, with 17 plants proposed along the California coast and two in Mexico. But removing the salt from seawater is an energy-intensive process that consumes more energy per gallon than most other water supply and treatment options. A new report from the Pacific Institute series Key Issues for Seawater Desalination in California describes the energy requirements and associated greenhouse gas emissions for desalinated water and evaluates the impact of short- and long-term energy price variability on the cost of desalinated water.

Energy requirements are key factors that will impact the extent and success of desalination in California. Key Issues for Seawater Desalination in California: Energy and Greenhouse Gas Emissions shows energy requirements for seawater desalination average about 15,000 kWh per million gallons of water produced. By comparison, the least energy-intensive options of local sources of groundwater and surface water require 0 – 3,400 kWh per million gallons; wastewater reuse, depending on treatment levels, may require from 1,000 – 8,300 kWh per million gallons; and energy requirements for importing water through the State Water Project to Southern California range from 7,900 – 14,000 kWh per million gallons.

“Beyond the electricity required for the desalination facility itself, producing any new source of water, including through desalination, increases the amount of energy required to deliver and use the water produced as well as collect, treat, and dispose of the wastewater generated,” said Heather Cooley, co-director of the Pacific Institute Water Program and report author. Conservation and efficiency, by contrast, can help meet the anticipated needs associated with growth while maintaining or even reducing total energy use and greenhouse gas emissions.”

Desalination is a reliable source of water, which can be especially valuable during a drought. However, building a desalination plant may reduce a water utility’s exposure to water reliability risks at the added expense of an increase in exposure to energy price risk. Energy is the largest single variable cost for a desalination plant, varying from one-third to more than one-half the cost of produced water. Because of its high energy use, desalination creates or increases the water supplier’s exposure to energy price variability.

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Key Issues in Seawater Desalination in California: Marine Impacts
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Key Issues in Seawater Desalination in California: Marine Impacts
Pacific Institute | December 11, 2013...
Summary
Desalination, like other major industrial processes, has environmental impacts that must be understood and mitigated. A new report from the Pacific Institute examines effects on...
Desalination, like other major industrial processes, has environmental impacts that must be understood and mitigated. A new report from the Pacific Institute examines effects on the marine environment associated with the construction and long-term operation of seawater desalination plants, including withdrawing water from the ocean and discharging the highly concentrated brine.

“If and when we build plants in California, we must ensure that the plants are built to the highest standards given what we know now,” said Cooley. “Additionally, monitoring of existing and proposed desalination plants is crucial to improving our understanding of the sensitivity of the marine environment and helping promote more effective operation and design to minimize ecological and biological impacts in the future.”

Modern reverse-osmosis desalination plants, such as those planned or proposed on the California coast, take in large volumes of seawater – generally two gallons are withdrawn for every gallon of freshwater produced – and pass it through fine-pored membranes to separate freshwater from salt. The highly concentrated brine is then typically disposed of back into the ocean.

With the majority of desalination plants extracting water directly through open water intakes in the ocean, there is a direct impact on marine life. Fish and other marine organisms are killed on the intake screens (impingement); organisms small enough to pass through, such as plankton, fish eggs, and larvae, are killed during processing of the salt water (entrainment). The impacts on the marine environment, even for a single desalination plant, may be subject to daily, seasonal, annual, and even decadal variation, and are likely to be species- and site-specific.

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