Marin Municipal Water District officials abandoned a controversial proposal last month to expand the Nicasio Reservoir, the county’s second-biggest, citing a sharp rise in project costs.
For the past year, the water district, which serves over 191,000 residents in central and southern Marin, had promoted the expansion as a cost-effective option to boost its water supply. The plan involved installing a 280-foot-long, 4.4-foot-high inflatable gate on Seeger Dam, which would have increased the reservoir’s capacity by 3,700 acre-feet, or about 16.6%.
At the district’s Aug. 19 board meeting, staff revealed in an updated analysis that the original project cost estimate of about $15 million had surged to between $37 and $54 million. That was enough for the district board to direct staff to halt the project’s environmental review and withdraw the proposal, though no formal vote was taken…