New Hogan Reservoir serves San Joaquin County and the city of Stockton. But this year's low water levels, could affect both drinking water and irrigation supplies.
The water level in New Hogan Reservoir in Calaveras County has dropped to about one-third of capacity.
New Hogan serves Stockton East Water District which in turn supplies drinking water for the City of Stockton and irrigation water for farmers in east and north San Joaquin County.
Stockton East General Manager Scot Moody says, unlike other reservoirs, New Hogan doesn't use sierra runoff but is entirely dependent upon rainfall.
"I know we are considerably off from where we would want to be this year, with a dry November, dry December and nothing forecast in early January, we are definitely concerned," says Moody.
Moody expects to know how much water will be available by April.
"First 20,000 acre feet is guaranteed to urban contractors and so from there we have to take a look and see what's going to be left," says Moody.
If there is no rain, farmers may have their irrigation water supplies cut and be forced to rely upon ground water.
Legislation introduced in the California state Assembly would create the Lower American River Conservancy to improve, protect, preserve and possibly expand the 5,000-acre American River Parkway.
January brought above-average rainfall and snow to much of California, partly due to El Niño. But forecasters say the ocean warming condition is "taking a break" for the next week or longer.
The U.S. Drought Monitor says, other than a slight reduction in exceptional drought in the northern Sierra, it needs more time to assess impacts of the recent moisture on California's long-term drought.
California regulators have made modest adjustments to water conservation requirements for cities.
The second measurement this winter of snowpack in the Sierra Nevada was 130 percent of average. State water officials say the snowpack will help reservoir recovery.