Environmental nonprofit Orange County Coastkeeper said last week that a water intake system once ruled out for a controversial proposed desalination plant in Huntington Beach could be viable if it is used differently.
In 2014, an expert panel chosen by the California Coastal Commission and plant builder Poseidon Water ruled that slant well intakes were not technically feasible because they would draw too much water from the groundwater basin controlled by the Orange County Water District.
However, the two groups created another panel during that time to further study slant wells, and the panel concluded that if the intakes were situated at a certain angle and pumped water at a slower rate, they could reduce the impact on OCWD's groundwater basin, according to a memo published by the panel Friday.
"Using the new modeling, slant well intakes could produce the amount of water to run the plant," said Ray Hiemstra, associate director of Coastkeeper.
Poseidon's current plan is to use open-water intakes used by the neighboring AES natural gas power plant at Newland Street and Pacific Coast Highway. It would need to take in 100 million gallons per day of seawater to produce 50 million gallons per day of potable water.
According to the recent findings, the slant wells could intake as much as 108 million gallons per day of seawater while minimizing the amount of groundwater, Hiemstra said.
"Ratio varies from 8% from [the groundwater basin] to about 36%," he said.
Coastkeeper and other environmentalists have been asking Poseidon to use some type of subsurface intake and use the sand as a natural filter, which they say is less detrimental to marine life.
However, Poseidon Vice President Scott Maloni said the memo is not changing the company's mind on which intake system it wants to use. Maloni said using slant wells would require placing 30 or more wells along the coastline and would have a negative impact on beach accessibility.
"We're adamantly opposed to any desalination facility that uses slant wells because it would intercept water that we put into the seawater intrusion barrier [groundwater basin]," he said. "I don't think the outcome of that memo is impactful because the report said that wells are an infeasible technology."
Poseidon is one permit away from being able to start construction on its $1-billion project, requiring a construction permit from the Coastal Commission. The project was heard in November 2013, but the state agency allowed the company to pull its application to allow for further studies on subsurface intakes.