The recent storms allowed California to suspend drought reduction orders that had been imposed during the summer.
Cities and irrigation districts are now free to capture runoff that was not available due to orders. Officials have warned they could snap back if the state gets another period of dry weather.
“We are still in a period of drought and no precipitation is expected for the next 10 to 12 days,” read part of Tuesday in an email from spokesperson Ailene Voisin of the State Water Resources Control Board.
The ordinances had authorized the use of water already in reservoirs, which helped many areas through the 2021 irrigation season. This includes the districts of Modesto, Turlock, Oakdale and South San Joaquin.
But the four warned the water could run out if the ordinances continued into 2022. They also sued the state agency in September, saying it was illegally interfering with long-standing river rights.
State officials said they need to reduce diversions to maintain enough water for fish and water quality. By far most of the orders were for the waterways of the Sacramento-San Joaquin Delta. About 10,300 organizations and individuals hold rights along the tributaries.
Runoff was only 47% of the average in the central Sierra Nevada during the hydrologic year ending Oct. 1, the California Department of Water Resources said. This followed a year of 62%. The effects were mitigated by the storage of 2017 and 2019 above average.
The recent rain and snow have arrived early in the storm season, which runs mainly from November to March. Storms brought 16% of the average annual rainfall to the central Sierra, DWR said, but officials warned of possible drier conditions ahead.
They base this in part on the emergence of La Niña, a cooling of the eastern Pacific Ocean that tends to deflect storms away from California.
Despite the runoff from the mountains, storage has not increased much in the main reservoirs in the Modesto region. They need to release extra water in the fall to make it easier for the salmon to spawn.
The Don Pedro reservoir, owned by the Modesto and Turlock irrigation districts, was at 49% capacity on Wednesday. The New Melones reservoir, used by the Oakdale and South San Joaquin Irrigation Districts, was at 34%.