California’s water woes are not going away. Recent reports issued by the National Oceanic and Atmospheric Administration say a possible El Nino year may not be enough to break the drought. Even though there is an 80% chance of the next winter being an El Nino, only 1 El Nino in 7 has the power to alleviate California’s current water shortage.
Replenishing California’s water is not just a matter of refilling the drying lakes and reservoirs which are now at 20% capacity. To make up for the reduced water supplies at the state level, local agencies and farmers are pumping additional ground water for irrigation.
Doug Parker, director at University of California Institute for Water Resources says, “We really need to be prepared for more drought.”
Because of the mechanics of warming water and air affecting global air circulation, the El Nino condition does not guarantee a wet year. Mr. Parker says, “There’s a pattern of dry years happening so there’s a higher probability that next year will be a dry one.”
During dry years when water supplies are restricted, ground water is pumped from aquifers to make up water needed for both domestic and agricultural needs. Pumping out more ground water than is available to recharge the aquifers leads to salt water intrusions. The salt contaminates the remaining ground water, often making it unfit for drinking or irrigation.
El Nino conditions bring heavier precipitation just 1/3 of the time. Recent El Nino storms in 1982-83 and 1997-98 brought torrential rains, flooding and heavy destruction but still did not restore the ground water. Parker’s concerns are echoed by Mike Dettinger, USGS Hydrologist and research associate at Scripps Institution of Oceanography.
The wet / dry El Nino / La Nina cycle is thrown out of balance in already droughted years. Mike Dettinger warns, “In a major drought situation like the past two years, it is more important to think about the range of El Nino outcomes than to depend on an average.”