There are a number of ways to expand water supply in San Diego. San Diego Coastkeeper supports following the route of reduce, reuse, recycle, before attempting to find new sources.
First and foremost, we need to focus more on water conservation, or reducing the amount of water we actually use. It’s the easiest, cheapest way to boost our water supply. It is also the focus of the Be Water Wise 20 Gallon Challenge, a campaign to reduce the amount of water used per household by 20 gallons per day. Conservation techniques can include anything from taking shorter showers to starting a compost bin so you use less water running the disposal and much more.
Rainwater harvesting and greywater systems reuse water without treating it first. This is also a fairly simple way to increase supply, because less water is wasted. Capturing rainwater allows its use for irrigation and helps avoid using potable water for the purpose. It’s easily done at home, and requires very little installation.
Greywater also can be used for irrigation, with the added bonus of reducing the amount of water sent to treatment plants and released into the ocean. Using greywater at home is more complicated than catching rainwater, as it requires a plumber to divert water exiting bathroom sinks, washing machines, and showers (all with very low dirt-to-water ratios) to landscaping outside the house (storage of greywater is not advised). The low level of detergents and dirt can actually be good for the plants, but keep it on your property and avoid runoff to the street.
Wastewater recycling, or Indirect Potable Reuse (IPR) if used for drinking water, falls into this category. Sometimes called “toilet to tap” by detractors, the process uses advanced treatment processes to treat wastewater to levels even cleaner (page 108 of this report) than San Diego’s typical drinking water, then put it back in the water supply. A Demonstration Project is underway to prove the process safe for San Diego. If it succeeds, wastewater recycling could be the next step in increasing our water supply.
Purple pipe is the other side of wastewater recycling, where wastewater is only partially treated and used for irrigation. Coastkeeper is in favor of this strategy only in targeted areas, as it requires a separate plumbing system and is therefore very expensive to install.
After experimentation with the above sources, it might be necessary to look for new water sources. Further importation of water is theoretically possible, but San Diego already imports more than 80 percent of its water from the Sacramento/San Joaquin Delta and the Colorado River, supplies not under our control. Increasing that percentage would be risky, so any further imports would have to be done in combination with other techniques.
Desalination is another option, but while local, this source of water has a number of problems. A major one is the intake pipe: open-ocean intakes function as vacuums into the sea or lagoons where they suck in and kill marine life, a major issue. Subsurface intakes are better, as they take in salt water from under the sand and so greatly limit fish kills. The process of desalting ocean water is very similar to Indirect Potable Reuse, but because of the higher salt content, it is very energy-intensive. Besides the desired freshwater, the process also yields a very saline chemical-laden brine – diluted, the brine can be released into the ocean, but it can poison marine life if too concentrated. Menachem Elimelech, director of the environmental engineering program at Yale, said in a News Hour interview, “Desalination of seawater, because it is energy intensive should always be as a last resort…. It can be and should be part of the portfolio for water supply but only after all other measures are done.” Coastkeeper believes that desalination could have a place in San Diego’s water portfolio, but only on a limited scale and only using subsurface intakes.
Environmental groups challenging the Carlsbad Desalination Plant scrutinize the project because as proposed it's the region’s most expensive and energy intensive water supply option. As one of the environmental groups leading the charge in challenging the Carlsbad Desalination Plant, we’re clearing the air about a few misconceptions.
Truth #1 Our cases have merit.
Procedural deficiencies at every reviewing agency have marred the approval process for the plant. While some suggest we are engaging in superfluous lawsuits, this desalination plant will be the largest in the western hemisphere and may set precedent for all other projects. We must ensure it is as protective of our environment as possible. Yet, our regulatory agencies have taken an “approve first, ask questions later” approach that could lead to disastrous consequences.
Our efforts, and those of our partner organizations, have already improved the project dramatically by ensuring carbon offsets and wetlands mitigation to offset some impacts from the proposed project.
Truth # 2 We don’t oppose desalination.
We support a comprehensive water policy - prioritizing how we get and use our water based on cost, environmental and energy impacts, and reliability. First, we need to exhaust conservation and water efficiency efforts. After the City of San Diego instituted mandatory water use restrictions last year, outside water use dropped 13 percent. In a county where nearly 50 percent of our water goes to residential use (60% of that for landscape irrigation), conservation can provide huge savings.
Second, we need to aggressively pursue water reuse. The City of San Diego is currently exploring Indirect Potable Reuse, which recycles wastewater to drinking water standards above that of our current supplies. Rainwater harvesting, grey water and non-potable water reclamation provide other opportunities to access hundreds of millions of gallons of recycled water daily.
Both conservation and reuse are cheaper, more energy efficient than desalination and can dramatically reduce ocean pollution without killing fish in the process.
Truth # 3 Desalination is the most expensive way to enhance local water supplies.
Conservation saves consumers money by reducing water and energy bills. Augmenting local reservoirs with recycled water uses the same treatment technologies as desalination but at 40 percent of the cost. And while Poseidon continues to claim on its website that its project will be developed at no expense to taxpayers, the truth is the project will receive $350 million over the next 25 years in public Metropolitan Water District subsidies and has a pending $530 million request in tax-free Private Activity Bonds to finance the project.
Truth # 4 Desalination is also the most energy intensive water option for San Diego.
Estimates show that 19 percent of California’s energy usage is for the treatment, movement and delivery of water. Between 3 and 5 percent of the state’s energy is used simply to move water from northern to Southern California, but desalination requires more. It also uses one third more energy than recycling wastewater.
Truth #5 If it sounds too good to be true, it probably is.
We’ve been asked to stand aside and support public opinion. However few important battles (civil rights, environmental protection, etc.) have been won without taking unpopular positions. The project’s popularity is based on the allure of a seemingly inexhaustible ocean resource and the small fortune Poseidon has paid in public relations and lobbying efforts to promise everything to everybody: for San Diegans, an endless supply of cheap water; for taxpayer/consumer groups, a guarantee of no subsidies; for organized labor, good union jobs; and for environmental groups, full environmental mitigation (the company claims the plant will be a net benefit for wetlands and ocean habitat). Poseidon is San Diego’s real-life Santa Claus!
So, if you are asking yourself, “how does this add up?” you’re ahead of the folks that have approved the project to date. A better question may be, “why did so many appointed officials approve this project (almost always overruling staff recommendations) without asking these tough questions in the face of such obvious contradictions?”
This is the question we are trying to resolve through our challenges.
We all want the same thing for our region—a dependable, affordable and sustainable water supply. Rather than make decisions in a crisis, we’d like to see our region make strategic decisions that protect our citizens and environment from unnecessary costs and harm. That’s why we need to develop a more thoughtful, comprehensive water policy for the region that prioritizes lower-cost, lower-impact alternatives like conservation and efficiency and reclamation. Desalination should be a last resort in our water portfolio.
San Diego recently hosted the California Ocean Protection Council (COPC), a committee we haven’t seen in this region since 2005. Governor Schwarzenegger created the COPC to regulate ocean health in California, and the commissioners represent the state’s leading elected and appointed officials. As the executive director of San Diego Coastkeeper, the county’s largest water quality non-profit, I was pleased to see the council include panels addressing both the desalination issue as well as the growing threats from marine trash.
The desalination discussion, which included a distinguished panel of experts, focused on understanding the role of desalination in California’s future water supply. It is no surprise that Coastkeeper takes issue with the Poseidon plant planned for Carlsbad, but I agree with several of the COPC experts who advocated for the desalination dialogue to take place as part of a holistic and cohesive discussion that will define our water supply goals, vision and strategy for a diversified portfolio. The issue is not a yes or no vote for desalination, rather a conversation regarding conservation and water reuse as our first steps and environmentally friendly desalination in appropriate locations as a last option.
It is important for San Diegans to explore these other options first because we can make major impacts by more efficiently using what we already have. For instance, after initial mandatory water use restrictions instituted in the City of San Diego in 2009, outside water use dropped by 13 percent. This helped the city save almost 11,000 acre-feet of water. The Carlsbad desalination facility is planned to produce 56,000 acre-feet of water per year. With minor restrictions in outdoor water use, we’ve already matched 1/5 of the plant’s output in conservation, without impacting a single fish or emitting any greenhouse gasses.
Did it impact your quality of life? My guess is that it did not.
The panel also discussed how technological advancements have helped desal improve during the last decade (though it is still among the most expensive, energy intensive and environmentally damaging alternatives). Panel experts expressed concerns that we have come to the end of an era with these improvements, which were simply “low-hanging fruit,” and we shouldn’t expect the desal process to continue improving. As one panelist said, “it just takes a certain amount of energy to push salt through membranes.” In fact, in Southern California, desalination is the only option that requires more energy usage than the current most energy intensive water supply, importing water into the area.