The Sacramento Bee reported Thursday that the San Juan Water District board of directors approved the move this week.
The district serves more than 265,000 people in the Sacramento suburbs, including the communities of Citrus Heights, Orangevale and Folsom.
Most of its water comes from Folsom Reservoir, which the newspaper says has shrunk perilously low amid one of the driest winters in California history.
District General Manager Shauna Lorance says the call for conservation is not mandatory, but it could become so next month if the area doesn't get rain soon.
The district also is extending a request for a 20 percent cut in all water use that has been in place for months.
Get the latest on the California Legislature's final hours of work for the 2013-14 session.
Releasing reservoir water to keep salmon from dying is one of many tough water allocation decisions in this third year of the California drought.
California's drought is blamed for a big downturn in honey production.
Researchers say California has been overdrawing its water account for a century.
Researchers at UC Davis fear that California’s drought may soon claim its first victim, the Red Hills Roach. The tiny fish is losing its water. Scientists fear it may soon be pushed to extinction.