The prolonged drought in California affecting its water supplies is further exacerbated by diminishing snowpack in the Sierra Nevada mountains flowing through rivers and feeding the state’s reservoirs.
Insider reports that due to the historic mega-drought currently experienced in California, the water levels of its 1500 reservoirs have dropped by 50%.
As residents seek other water sources and droughts threaten the state’s water supplies, are desalination plants a sustainable solution to the state’s water challenges?
The Carlsbad desalination plant in San Diego, California, is the largest desalination plant in the U.S. Plans to build another one of similar size are underway in Huntington Beach, just 60 miles north of the Carlsbad plant.
Poseidon, the builder of Carlsbad’s desalination plant, first proposed to build the desalination plant in 1990 to Huntington residents.
Still, some were opposed to the idea and not convinced of its necessity. The firm is just awaiting approval for its plans from the California Coastal Commission.
The dispute between some of Huntington’s residents and Poseidon sheds light on the role of desalination plants as a water source for the drought-stricken state.
Role of desalination to prepare the state for a drier future
According to The Economist article “The promise and pitfalls of desalination,” the current drought in California is the driest 22-year period the southwest has seen in at least 1,200 years, prompting the state to reduce farmers’ water allocation to only 5% of their normal. The state told farmers that they would be receiving only 5% of their usual allotment.
The Carlsbad plant supplies water to 3.3 million southern Californians. It was planned in 1998 for two reasons:
- Unlike other parts of the state, Southwesterners don’t have enough aquifers to tap into when rivers run low.
- Secondly, the cuts made to their water supplies in the 1980s due to a severe drought scared local managers to look for alternative water sources. Now the plant supplies 10% of the local water needs.
However, the cost of water in San Diego is much higher than in LA. And the fact that water coming from desalination plants costs much higher to produce should drive residents to use water more efficiently.
Due to the city’s conservation efforts, 2000 water demands have decreased since 2000 amid population growth leading residents to question the plant’s necessity.
A logical solution to water scarcity?
According to The Economist, while desalinating water seems like a logical solution to water scarcity, it has the following pitfalls:
- Desalination plants discharging salty brine back to the ocean harm marine life, a major concern for environmentalists.
- The reverse-osmosis process used to remove salt from water is energy-intensive, and
- Desalination is the most expensive among other alternative water sources.
Policymakers want desalination to be the last resort as a solution to continuing water supplies, and other options such as conservation, recycling, and capturing stormwater should be considered first.
However, desalination can be a part of the state’s water mix to boost water security as technology improves.
Researchers are thinking of other ways to reduce the environmental impacts of desalination plants, such as finding ways to use brine other than discharging it back to the ocean and using solar power to run desalination plants.
PHOTO CREDIT: By © Frank Schulenburg, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=106155670