Several environmental groups asked San Francisco on Tuesday to reduce its diversion of Tuolumne River water.
They said chinook salmon and other wildlife suffer from the current operations, especially the river stretch in and near Modesto.
At a meeting of the San Francisco Public Utilities Commission , the groups urged more conservation and wastewater recycling. The agency responded that these “single-issue activists” do not understand the city’s needs.
San Francisco secured rights in 1913 to about an eighth of the Tuolumne, which arises at about 13,000 feet in Yosemite National Park. Most of the water diversion is at Hetch Hetchy Reservoir, built just inside the western park boundary to the dismay of early preservationists.
The system provides most of the water used in San Francisco and varying proportions to 26 other locales in San Mateo, Santa Clara and Alameda counties. It serves a total of about 2.7 million residents and also taps wells, local watersheds and other sources.