HUNTINGTON BEACH, Calif. — For more than two decades, Orange County, California has debated whether to build a beachfront plant to convert salt water from the Pacific Ocean into drinking water in hopes to protect against droughts like the one currently affecting the country’s most populous state. .

On Thursday, Poseidon Water’s $1.4 billion proposal came under critical scrutiny from the California Coastal Commission, which is charged with protecting California’s scenic shorelines. A vote was expected later in the day.

Poseidon and his supporters, including Governor Gavin Newsom, say the Huntington Beach plant will produce 50 million gallons of water a day, which is crucial to help reduce state and federal water supplies after years of drought. Newsom, a Democrat, recently told the Bay Area News Group editorial board that a denial would be a “big setback” and “we need more tools in the damn toolbox” to fight the drought.

“The need for this project is essential and beyond question,” Poseidon’s attorney DJ Moore told the Coast Commission. “California is at an inflection point on water.”

But environmental groups and staff at the commission, which reviewed the plan, oppose it. They argue that it will damage marine life by killing tiny organisms that form the basis of the ocean’s food web. They also say it is vulnerable to flooding and other hazards. And some in the water industry say the cost of desalinated water is too high and not needed in an area with access to cheaper water sources.

“The project would kill marine life in approximately 275 million gallons of seawater per day,” Tom Luster, the commission’s desalination expert, told the panel.

The long-awaited meeting in front of the 12-member commission is seen as the last big hurdle in building the plant. The panel heard hours of comments on Thursday from dozens of people crammed into a hotel meeting room in the town of Costa Mesa, Orange County, in addition to those tuning in online.

At the meeting, supporters wore orange and yellow construction vests and held up signs saying “support desal!” Opponents carried signs that read ‘No Poseidon’ and ‘Don’t sell our coast’ and included a woman who wore a plankton costume and held a sign that read ‘I’m a plankton – please don’t kill me !”

California has spent most of the past 15 years in drought conditions. Its normal wet season that runs from late fall to late winter has been particularly dry this year, and as a result, 95% of the state is classified as severe drought.

Last summer, Newsom urged residents to cut their consumption by 15%, but since then water consumption has only fallen by around 3%. Some regions have begun to introduce generally mild restrictions, such as limiting the number of days lawns can be watered. Stricter restrictions are likely later in the year.

Much of California’s water comes from snowmelt and with a much lower than normal snowpack, state officials told water agencies they would only receive 5% of what they asked of state water supplies beyond what is needed for critical activities like drinking and bathing.

Desalination takes seawater and removes salt and other elements to make it drinkable. These elements are discharged into the sea, while the water can be piped directly to consumers or used to replenish a groundwater basin. The country’s largest seawater desalination plant is already operating in neighboring San Diego County, and there are coastal plants in Florida as well.

The idea of ​​desalination has been debated for decades in Huntington Beach, a coastal community southeast of Los Angeles known as “Surf City USA” that depends on its sand and waves for tourism. Discussions about the project have also recently focused on the impact of climate change on regional water supply and sea level rise in the low-lying coastal area where the plant would be built.

More than two decades ago, Poseidon proposed to build two desalination plants – one in San Diego County and one in Huntington Beach. The San Diego County plant was approved and built, and desalinated water now represents 10% of the San Diego County Water District’s water supply.

But the Huntington Beach project has experienced many delays. In 2013, the Coast Commission expressed concern that the proposed use of water intake structures to rapidly draw large volumes of water from the ocean would harm marine life. Poseidon, which is owned by Brookfield Infrastructure Partners, conducted additional studies and resubmitted the plan with a proposal to mitigate marine damage through the restoration of nearby wetlands.

Last month, panel staffers released a 200-page report opposing the project, saying it fails to comply with marine life protection policies and policies to minimize the risk of tsunamis and disasters. sea ​​level rise. Environmental groups have raised numerous objections and oppose the use of water intake structures that pull water for desalination above the ocean floor rather than ‘below.

“This proposal is so fundamentally flawed that no amount of mitigation credit is going to fix it,” Sean Bothwell, executive director of the California Coastkeeper Alliance, told the panel. “It’s a disaster.”

Some Thursdays also debated the scale of local demand for desalinated water. Orange County has an extensive groundwater basin and recycles wastewater, making the region less dependent on imported water than San Diego. The Orange County Water District, which has announced plans to purchase Poseidon’s water, manages the basin, which helps meet approximately 75 percent of water demand in the northern and central parts of the county.

Poseidon argues that the region would still benefit from the closure of a drought-tolerant water source, as would inland communities and states that may have increased access to imported water supplies once the county will be able to draw on desalinated water. Steve Sheldon, chairman of the Orange County Water District, said desalinated water is more expensive now, but he expects the cost of imported water to also rise over time.

Critics say the area would be better served economically and environmentally by focusing more on recycling, noting that an expansion of the county’s famous sewage recycling program is already underway. Paul Cook, general manager of the Irvine Ranch Water District – a local water retailer – said he didn’t want to buy expensive and unnecessary desalinated water for his customers, which would drive up household water bills.

But Kenny Williams, president of the Orange County Federation of Labor, said while the plant’s impact on marine life and other hazards can be addressed, the drought is a threat to the way of life. Southern Californians.

“We can afford a few extra dollars on our water bill. We cannot afford the taps to run dry,” he told the commission.