Nation’s largest ocean desalination plant goes up near San Diego; Future of CA coast?Leave a Comment
Paul Rogers San Jose Mercury News CARLSBAD – January 24, 2015
On sunny afternoons, this stretch of beach 35 miles north of San Diego presents a classic Southern California backdrop: joggers, palm trees and surfers, flanked by waves rolling in and pelicans soaring overhead. But just across the road, one more scene, unlike any other in the state’s history, is playing out: Much more than 300 construction workers are digging trenches and assembling a vast network of pipes, tanks and higher-tech gear as three massive yellow cranes labor nearby. The crews are constructing what boosters say represents California’s most effective hope for a drought-proof water supply: the biggest ocean desalination plant in the Western Hemisphere. The $1 billion project will present 50 million gallons of drinking water a day for San Diego County when it opens in 2016. Because the 1970s, California has dipped its toe into ocean desalination –speaking, organizing, debating. But for a assortment of reasons — mostly cost and environmental issues– the state has never taken the plunge. Until now.
Fifteen desalination projects are proposed along the coast from Los Angeles to San Francisco Bay. Desalination technologies is becoming a lot more effective. And the state is mired in its third year of drought. Critics and backers alike are wondering irrespective of whether this project in a town far better known as the household of Legoland and skateboard icon Tony Hawk is ushering in a new era. Will California — like Israel, Saudi Arabia and other arid coastal regions of the globe — ultimately turn to the ocean to quench its thirst? Or will the project ultimately prove that drinking Pacific seawater is too pricey, too environmentally harmful and too impractical for the Golden State?
“Everyone is watching Carlsbad to see what is going to occur,” mentioned Peter MacLaggan, vice president of Poseidon Water, the Boston firm developing the plant. “I think it will be a growing trend along the coast,” he mentioned. “The ocean is the one particular supply of water that is genuinely drought-proof. And it will generally be there….
….Practically each discussion about desalination begins and ends with cost. Desalinated water usually fees about $2,000 an acre foot — roughly the quantity of water a family of 5 makes use of in a year. The expense is about double that of water obtained from creating a new reservoir or recycling wastewater, according to a 2013 study from the state Department of Water Resources. And its price tag is at least 4 instances the expense of obtaining “new water” from conservation methods — such as paying farmers to set up drip irrigation, or giving rebates for property owners to rip out lawns or acquire water-effective toilets. “We look out and see a vast ocean. It appears obvious,” said Heather Cooley, water director for the Pacific Institute, a nonprofit research organization in Oakland. “But it really is cost prohibitive for most places in California.” In Carlsbad, two gallons of seawater will be needed to produce every gallon of drinking water. And to eliminate the salt, the plant will use an massive amount of energy — about 38 megawatts, enough to energy 28,500 houses — to force one hundred million gallons of seawater a day through a series of filters. The process, known as reverse osmosis, removes salt and other impurities by blasting the water at six times the pressure of a fire hose by way of membranes with microscopic holes….
…Right after enduring extreme water shortages through a drought in the late 1980s, Santa Barbara voters agreed to invest $34 million to create a desalination plant. It opened in 1991 and offered water for four months. When the drought ended, the city shut it down. Water from reservoirs and other sources was significantly cheaper. Similarly, Australia spent additional than $ten billion constructing six massive seawater desalination plants for the duration of a extreme drought from 1997 to 2009. Currently, Cooley noted, 4 are shut down due to the fact when rains finally came, the expense of the water became noncompetitive. “We run the threat of building facilities that we don’t use,” Cooley mentioned. “And that is a waste of money.”…
…. Santa Cruz city officials in August shelved plans for a desal plant following environmental activists raised fears that the new water may trigger additional growth. Marin County studied a desal project, then dropped it when water use declined. Lengthy-running plans to develop a desal plant in San Francisco Bay close to Concord have been shelved this year when the region’s biggest water districts decided they could obtain water additional cheaply through recycling and other signifies. A different essential concern looming huge is how to get the seawater devoid of hurting the marine environment. The Coastal Commission authorized the Carlsbad plant and its open-ocean intake system. But new scientific studies and changing laws imply that most future plants most likely will be necessary to bury intake pipes and pump water at a reduced price to lower impacts on fish and the millions of larvae, eggs and other sea life that can be killed.
“These organisms grow to be factors — like fish — and we normally have to be cautious of the perspective that ‘Oh, this is just one tiny piece,'” stated Charles Lester, executive director of the Coastal Commission. “It all adds up.”….
For the Carlsbad plant Poseidon was necessary to make 66 acres of wetlands in San Diego Bay to offset the plant’s environmental harm. It also have to blend its brine at a 5:1 ratio with other seawater ahead of flushing it back into the ocean so it will not harm marine life. Other projects will have to do all these factors to get state permits. But some specialists say the plants are coming anyway. “In the subsequent ten years you are almost certainly going to have three massive plants constructed in Southern California and yet another plant or two in Northern California,” Pankratz stated. “The trend is toward far more desal. They are the most reasonable insurance coverage policy against a extended, protracted drought.”