Marin Water pressed on when it would actually use its drought insurance pipeline

What's happening: The Marin Water board approved a $2.66 million partnership agreement with the U.S. Army Corps of Engineers Tuesday, according to a staff report from Shaun Horne, Director of Watershed Resources, with the district covering $658,333 of that cost from funds already budgeted for the project. The agreement funds design of an 18,000-foot segment of the Atmospheric River Capture pipeline, known as ARC. The staff report states a separate federal environmental review must occur before the board considers approving the project itself; the report describes Tuesday's approval as funding design work. The vote came alongside a board debate over how the district will decide when to activate ARC during a future drought.

Why it matters: ARC is a pipeline project that would capture surplus Russian River storm water and store it in Nicasio Reservoir for use during future droughts, according to Marin Water's project materials. The district's website states the project is still in early design and environmental review, with construction not scheduled to start until 2027 and the system not expected to operate until 2030. Water resources director Paul Sellier presented a separate staff report to the board Tuesday stating the district's reservoirs currently sit at 92% capacity and 111% of average for this date.

Marin Water's website states the district draws most of its water from a 33-square-mile local watershed and that reservoirs don't always fill during the winter, especially in dry years. The district's website also describes the 2021-2022 drought as bringing the district close to exhausting local supply, triggering a water shortage emergency and what the district calls some of the most severe water use restrictions in district history.