The last three years have been the driest in California's history. Now water agencies across the state are concerned about possible shortages for next year and beyond.
"We are living in unprecedented conditions," said Alvar Escrito-Bou, a senior fellow with the California water policy center. "We haven't seen this before. It's normal that after three years of drought -- especially if we don't get rain this fall or winter -- we could face big challenges on the supply side."
Most of California urban water agencies believe they have enough supplies to last through another seven months of drought, but nearly 20% of them say they could be facing significant shortages.
"It all depends on how conditions develop," said Demetri Polyzos a Resource planning team manager at Metropolitan Water District. "If conditions stay dry as they have been then we again we are in a situation where for pockets of our service area we will not have adequate supplies."
The California Department of Water resources annual Water Supply and Demand report identified that statewide, nearly 82% of water suppliers did not project water supply shortages in the next year. However, nearly 18% projected water supply shortages without mitigation actions.
But the percentage of water suppliers expecting shortages varies greatly by hydrologic regions, or natural areas of water flow throughout the state.
In the South Coast region, which includes much of Los Angeles, Ventura, Orange and San Diego counties, about 12% of water suppliers expect a shortage. In the San Francisco bay region, it's 60%.
"We could see conditions worsening especially if we don't get enough rain this fall or winter," said Alvar Escrito-Bou, "So next year especially those who rely on one supply or one reservoir or one single supply can be more vulnerable than places have a portfolio of options."
The Metropolitan Water District says recent water conservation efforts are working but need to continue to prevent water shortages.
"The conservation efforts have helped the sacrifices folks are making is helping us stretch those supplies that we can manage through these dry years," said Polyzos.