As rising temperatures and shifting rainfalls continue to exacerbate water problems for growing populations, desalinization of sea water, long a grail for water starved localities, will come into serious play. Marin County, dependent on rain-fed reservoirs and water piped in from the diminishing Russian River, is taking a serious look.
The desalination plant would take San Rafael Bay water and subject it to various forms of treatment to produce drinkable water through reverse osmosis technology.
The plant would be situated on MMWD-owned land near Pelican Way in San Rafael. Bay water would be piped from an intake at the end of a newly refurbished Marin Rod and Gun Club pier near the Richmond-San Rafael Bridge.
The desalination process would convert about half the volume of water taken from the bay into drinking water. The remaining water, or brine, would have a dissolved solids concentration about twice that of raw water. Brine would be blended and discharged back to the bay through an outfall operated by the Central Marin Sanitation Agency, which treats municipal and industrial wastewater generated in central Marin. Pretreatment of raw water to remove solids would generate sludge. This sludge would be hauled for disposal to the Redwood Landfill, according to the report.
Not everyone thinks a big plant is a great idea.
At a district board meeting Wednesday, about a half dozen people spoke against the plant proposal, criticizing everything from the purity, or lack thereof, of bay water, to the cost of the project – about $115 million.
You can read the whole report here, and see a chart of rain fall at Lake Lagunitas since 1850, here