According to the engineering report of the Marin County seawater desalination pilot project, remove salt and filter the sticky things in San Francisco Bay, and the water is perfect for drinking.According to the study, the problem is that the cost of building a large plant to dilute water is between $0.111 billion and $0.173 billion.The report, which will be submitted to the Marin City Water Authority on Thursday, analyzed a small reportThe area's scale desalination plant, built as a pilot project, has been operating for 11 months since June 2005.The study is part of the information required by the regional commission later this year to decide whether or not to fully implement itMarin should set up a scale plant that provides up to 10 million gallons of drinking water per day, about 20% of its daily use.This is not only an important issue for Marin, but also an important issue for the entire state as the threat of water supply decreases and catastrophic drought increases with global warming.In fact, there is not enough water in the water area.-Seven reservoirs mainly from the local area-Supply all of its customers during the drought.If completed, the Marin desalination facility will be the largest desalination facility in the Bay Area and the only desalination facility in the state that has access to a closed Bay and estuary.The system will use a reverse osmosis filtration system to remove salt from water taken from the Bay.The pilot plant was built in San Rafael, near Richmond-The San Rafael Bridge is probably a location for a larger facility.The current plan is to mix the salt water extracted during the desalination process with the treated wastewater from the Marin central sanitation area, which experts believe will be a more natural by-product for disposal to the Bay.The study found that a desalination plant that produces 5 million gallons a day costs $111.2 million construction, including upgrade of distribution system, $4.Annual operating costs of 1 million.A factory that supplies 10 million gallons a day costs $173.$3 million and $12.Annual operating costs of 7 million.Despite the high cost, it concludes that "desalination can be feasible, reliable and dry --Drinking water source."Given the increase in construction costs over the past five years, these figures are in line with what we expected," said Paul Helliker, managing director of the water district, with 190,000 customers in southern and central Marin.Helliker said that even now, the water supply capacity in the area has reached 75%, below the average level at this time of year.He said: "Just pointing out that our water supply is not safe."The area is currently delivering some supplemental water from Russian rivers to its customers, but the only pipeline available has reached capacity.The plan is to build another pipeline to meet the needs of drought conditions, however, Water Authority officials are now concerned that due to disputes over water rights in Sonoma County, degradation of the aquifer and regulatory action on endangered fish, the Russian River may be completely cut off.Helliker said the National Oceanic Fisheries Agency will soon issue a report outlining how the water supply system of the Sonoma County Water Authority is hurting the endangered coho salmon."This is definitely a worrying situation," Helliker said ." Marin water district is preparing an environmental impact report on the desalination plant, which is expected to be released in the spring.The board hopes to make a decision later this year on whether to continue.