California Drought Folsom Lake Jan 2014
Truck tires are shown in the mud at the bottom of Folsom Lake, in California, which is at 17 percent of its capacity, Jan. 22, 2014. Reuters

California's State Water Resources Control Board is expected to approve emergency water-use restrictions on Tuesday as its reservoirs evaporate to their lowest levels in decades and the state's three-year drought continues.

Nevada’s Lake Mead, the Southwest’s biggest source of drinking water stored from the Colorado River, has fallen to its lowest level since its creation in the 1930s, according to Water-data.com. Northern California’s Lake Oroville has fallen to 39 percent capacity, half that of its historical average, according to state data.

The state’s action could be just the first step and would ban residents from using water in certain ways like allowing sprinkler water to run off lawns into the streets and washing cars without hoses that have a shut-off nozzle, the Wall Street Journal reported. An individual caught violating the strictures would be forced to pay up to $500, enforceable by local water agencies.

Governor Jerry Brown asked Californians to conserve water voluntarily in January, with a goal to cut water use by 20 percent. A May survey of water agencies showed consumption has fallen 5 percent.

About 13 percent of local water districts represented by the Association of California Water Agencies have passed mandatory restrictions, according to the nonprofit trade group. State and federal agencies have also reduced water shipments in California, costing farmers an estimated $800 million in revenue and 14,500 jobs in the Central Valley, according to the Center for Watershed Sciences at the University of California, Davis.