Los Osos could end its building moratorium by the end of the year and see new construction for the first time in decades under a plan led by the California Coastal Commission and San Luis Obispo County. The proposal could eventually bring 1% residential growth to a community that has been under a building ban since 1988. The history of Los Osos’ moratorium began with the septic tank discharge prohibition issued by the Central Coast Regional Water Quality Control Board in 1983. That agency found that the town’s 5,000 septic tanks were sending millions of gallons of effluent down the drain and into both the groundwater and the bay. The county then carried out a multi-decade struggle to site and fund a new water treatment plant, finally launched in 2012 and put into service in 2016.