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Coastkeeper Desalination Policy

By January 1, 2017October 2nd, 2017Desalination

Orange County Coastkeeper believes that ocean desalination will one day be a small part of California’s future water supply. Ocean desalination is a tool in the toolbox to use as a source for drinking water. Ocean desalination should be the last resort after all other local water supply options, including conservation, have been considered.

It is acknowledged that ocean desalination has the greatest environmental impacts, uses three times the energy compared to other water treatment processes, and is by far the most expensive (up to 4 times more than other processes). Water conservation, capture and recycling of stormwater and urban runoff, and indirect potable reuse (sewage to distilled water) are all superior sources of drinking water for the reasons stated.

If ocean desalination is chosen, the desalination facility should be located at a site where the water is needed, designed to minimize impacts to water quality, marine life and climate change, and sized to meet a documented need for water. It must also comply with the California Ocean Desalination Policy.
Coastkeeper’s opposition to the Poseidon Huntington Beach Desalination Plant is based on this policy.

The proposed project site is not based on need, but where costs can be minimized. Neither Poseidon nor the Orange County Water District has been able to prove or justify the need for this $1 billion plus project. In fact, it is not needed to guarantee reliable drinking water for the future. Rather than use the desalinated water as drinking water, the proposal plans to inject the water into the underground aquifer and re-pollute it, adding additional costs, for later use.

The proposed project design would utilize obsolete surface intakes with ineffective screens and unnecessarily discharge millions of gallons a day of hyper-saline brine into the water offshore near one of the most popular beaches in California. The project is also designed to produce an amount of water that assures a large profit rather than filling a documented need for water.

Poseidon Resources, a subsidiary of the giant and predatory Brookfield Corporation, is seeking to withdraw ocean water off Huntington Beach and convert that seawater into private freshwater sold to water districts to supplement or replace less expensive imported water and domestic groundwater. Poseidon promises this publicly subsidized, private facility will provide water reliability during droughts; but have yet to define reliability and the true cost of this project, can Orange County afford to gamble on this project?

Coastkeeper is not opposed to ocean desalination. Coastkeeper supports responsible desalination that considers the true costs of a desalination plant, including the burdens of financing, subsidies, energy demand, the environment, reliability, and aesthetics. We do oppose the use of expensive and environmentally damaging technology to augment water supply when more environmentally responsible and less costly alternatives exist.

Orange County should focus scarce rate and taxpayer resources on the most efficient and cost effective options for water security before approving Poseidon’s proposed desalination plant. The water agencies responsible for supplying Poseidon subsidies should first determine the real water supply needs of Orange County for the foreseeable future and develop a strategy to achieve those goals by using the best available technology with the lowest price and highest potential for water savings. Desalination may be one of the tools that water agencies and the public chose to pursue, but not before fully exploring and adopting the less expensive and proven options such as conservation or funding the expansion of the existing Ground Water Replenishment System (GWRS).

Environmental Impacts

The chief environmental harm caused by a desalination facility in Huntington Beach will be from the process of withdrawing water from the ocean and replacing it with highly concentrated brine discharge. In addition to the brine, Poseidon will use harmful chemicals to clean the membranes and the intake and outfall pipes, pushing these chemicals, along with seawater, into the ocean. Beyond chemical and brine pollution, early studies of desalination facilities found increased concentrations of copper, lead, and iron in the water column and sediment near discharge points. The source of this contamination was corrosion of desalination equipment, which leached heavy metals into the discharge. (Source: Pacific Institute)

The cooling water infrastructure used by coastal power plants is proposed for use by desalination advocates. However, as the independent Pacific Institute noted in their comprehensive report on California desalination plants, the California Energy Commission recently declared in a report that “seawater…is not just water. It is a habitat and contains an entire ecosystem of phytoplankton, fishes, and invertebrates.” The environmental harm from the existing cooling water infrastructure, commonly referred to as “Once-Through-Cooling,” is two-fold and is referred to as impingement and entrainment.

Impingement kills large organisms, such as fish, mammals, birds, and invertebrates when they are pinned against large screens over the intake pipes. Entrainment occurs when smaller organisms, such as small fish, eggs, plankton, and larvae pass through the intake screens and are killed during the cooling system’s operation before they are discharged back into the ocean. According to the Environmental Impact Report for the Poseidon HB project billions of fish larva will be entrained by their system. State Experts have identified the area impacted by the intake as stretching from Palos Verdes to Dana Point.

The impact to the natural marine environment due to Once-Through-Cooling is not completely understood, but the state of California is phasing out the use of this acknowledged harmful and antiquated technology by coastal power plants between 2010 and 2024. Proven, and less harmful alternatives to Once-Through-Cooling exist, and the continuation of this infrastructure for desalination will only continue to damage the marine ecosystem the state has a duty to protect our marine resources.


The Pacific Institute’s report declares that although the cost of desalination technology has fallen, “it remains an expensive water supply option” and “[d]esalination facilities are being proposed in locations where considerable cost-effective conservation and efficiency improvements are still possible.” The report continues to explain that California urban ratepayers rarely pay more than $1.00 to $3.00 per thousand gallons for their water and even the most efficient large desalination facilities will not have production costs fall below $3.00 to $3.50 per thousand gallons. Poseidon is proposing a cost of about $1900 per acre foot or $5.80 per thousand gallons. At that price, the cost of supplementing our existing groundwater supplies with desalinated water would be a shock to customers without significant subsidies.

As a real life example, a financial analysis done by Orange County Water District consultants determined that Poseidon’s water is likely to cost $1,922 an acre foot, about five times the current cost groundwater. This will have a substantial impact on Orange County Water District member agencies who are predicted to see a 32.7 percent increase in their groundwater pumping cost to pay for the plant just to begin and further price increases over the life of the project. Poseidon is now proposing a fifty-year take or pay contract.

Tying Orange County Water District to the project for far longer than the 30-year contract that the San Diego County Water Authority agreed to. SDCWA ratepayers have seen their water bills increase dramatically since the Poseidon Carlsbad plant started operation. Orange County should be skeptical when hearing claims that this facility is “different” or that processed seawater will cost less than other plants worldwide. Desalination plants in the Mediterranean, Australia or Florida are frequently and selectively cited as successful examples of existing desalination plants. However, it is important to realize that California possesses unique economic considerations not found in other global facilities.

These factors must be considered when comparing the cost per unit of water from a California plant to that derived from an Israeli or Algerian plant. One critically important cost variable is the source of the seawater. California receives its cold water from the north, and cold ocean water is more expensive to desalinate than warmer ocean water, such as the waters of the Mediterranean or Florida. Similarly, the cost of desalinated water increases as the salt content of the source water is more concentrated. For example, Gulf of Mexico has an approximate salinity concentration of 23 to 33 grams per liter while the Pacific Ocean has an approximate salinity of 38 grams per liter.

This seemingly small variation has a significant impact on the economics of any desalination facility, and should be considered when comparing the cost effectiveness of two plants in relation to each other. The costs associated with desalination facilities is highly site specific, and a thorough analysis on the cost-effectiveness of this technology must be completed prior to approving any project. (Pacific Institute)


Hidden subsidies obscure the true cost of desalinated water from ratepayers and give the appearance of desalinated water as a cost effective alternative to conservation and the expansion of existing water-saving technology, such as GWRS. For example the term sheet that Orange County Water District is currently considering requires Orange County Water District to provide Poseidon the full amount of up to $475 per Acre Foot ($26.6 million per year) in subsidies from the Southern California Metropolitan Water District. This subsidy reduces the apparent cost to Orange County ratepayers but it spreads the cost of the plant to ratepayers throughout southern California, including those in Orange County.

Poseidon has now acknowledged that the desalinated water it produces will NOT replace imported water on a one-to-one basis. With the state requiring GHG emission reductions Poseidon may need to purchase carbon offsets equal to about 83,500 MtCO2e.

The cost of carbon offsets fluctuates with the voluntary over-the-counter market. In order for Poseidon to buy carbon offsets it must further raise the cost of desalinated water. It is important to note that this is NOT a one-time cost. Regardless of the exact price of MtCO2e, this represents a new cost to the overall price per acre-foot.


Poseidon’s proposed desalination plant will require an enormous amount of electricity in a state where rolling blackouts and energy shortages are a living memory. Once operational, Poseidon’s plant will demand 840 megawatts of power per day, operating 24 hours a day. This demand is equivalent to adding 30,000 to 35,000 residential homes. This makes energy demand one of the single largest costs in operating the Poseidon plant, and a cost which can be highly variable if recent history is any indication (SEIR).

This exposes the water districts, and thus the ratepayers, to even higher costs.

As energy prices rise over time including contributing factors such as the closure of the San Onofre Nuclear Generating Station, the cost to produce desalinated water will increase at a rate greater than those non-energy dependent methods of water security, such as conservation or GWRS.

In addition, the independent think-tank Equinox Center has this to say about energy and desalination:
“Concerns about the availability and cost of energy, as well as greenhouse gas emissions, make energy intensity a key issue in assessing the different water options. Desalination is the most energy intense solution, with an estimated requirement of 4,100 to 5,100 (kilowatt hours) per acre foot.”

Energy costs make up a larger percentage of the cost of desalinated water than any other water supply. Thus, as energy prices go up they will disproportionately impact this water supply source.

Growth Inducement

In 2004, the California Coastal Commission identified growth inducement as potentially “the most significant effect” of proposed desalination projects. The operation of Poseidon’s Huntington Beach plant, along with other Poseidon desalination plants in southern California, could provide the resources for additional development of the region and further strain the natural coastal and inland environment of Orange County.