The mandatory cuts, due to the statewide drought, are the first in the city in nearly 25 years.
California farmers and cities are set to get more water, as state and federal officials ease drought-related water cutbacks because of recent rain and snow.
An overwhelming majority of Californians agree the state is facing a serious water shortage, but most are also opposed to mandatory rationing.
Thursday is the first day of spring, and the rainy season is quickly coming to a close and rainfall in the Bay Area has been far below normal for this time of year, potentially setting up a long-term drought for California, a National Weather Service hydrologist said.
In a 4-1 vote, the Alameda County Water District – which serves Fremont, Newark and Union City – voted to declare a water shortage emergency, forcing mandatory water restrictions on its 350,000 customers.
Oakland officials are reminding residents that some administrative and city services will be closed Monday as a result of budget cutbacks.