- François-Xavier Branthôme
- 2021 Season
Despite still being below average, conditions are slightly better than they were at this point last year.
Six years ago, in the middle of a crippling drought, California farmers throughout the Central Valley had to idle many of their fields.
Recent week deluge left many Californians shoveling snow as an “atmospheric river” swept the state. More precipitation was in the forecast for the following week, but experts worry that without repeated downpours over the next two months, the painful memories of the last drought could become reality again.
Last year was one of the driest rainy seasons on record, and prior to this week’s storm, the state was on pace for precipitation totals below the winter of 1976-77, the second-worst drought in California’s modern history.
Last weeks’ wet weather certainly helped the state’s water picture, but California remains well below average in total precipitation and storage in critically important reservoirs across the state. “We always welcome a good storm like this, but one week doesn’t make a winter, and one week doesn’t change a dry situation,” said David Rizzardo, chief of the hydrology branch at the state’s Department of Water Resources.
So far this season, the state has received only a few small or moderate “atmospheric river” storms. Atmospheric rivers form when high-powered winds drag a fire hose of tropical moisture across the surface of the Pacific Ocean, producing 500-mile (800 km) wide conveyor belts of water that can last for days. The largest storms can produce as much rain as a major hurricane; in a typical year, they provide nearly half of the state’s annual precipitation. They can cause major floods, and, in 2017, contributed to the emergency at Oroville Dam that prompted the evacuation of 188,000 residents.
But the state needs a series of them, desperately, to nourish the vast system of dams and canals that provide drinking water for millions and irrigation water for America’s most productive farm belt. “The difference between a wet year and a dry here is about four to six atmospheric river storms,” said Jay Lund, the co-director of the Center for Watershed Sciences at UC Davis.
And so far this year, the atmospheric rivers have been mostly a trickle. As of January 28, following the first full day of the latest storm, the season’s rainfall was still about half what it should be for this time of year.
The U.S. Drought Monitor already lists 75 percent of the state in a severe drought, with 100 percent of the entire state “abnormally dry.”
Water levels were 31% below normal in the state’s largest reservoir, Shasta Lake. Millerton Lake, a major reservoir that captures water from the Central and Southern Sierra, is less than a third full.
The Sierra snowpack — runoff from which is critical to filling reservoirs in the summer and fall — was at 58% of normal for the date.
Still, many water managers are wary of sounding another drought alarm. There are still two more months of potential rain and snow to come before the wet season unofficially ends, and water officials don’t want to cause a panic unless they absolutely have to. “With the worldwide health crisis, people already are crisis-weary with COVID-19 and related housing and job disparities. And the last thing you want to do is really pile it on,” said Amy Talbot, water efficiency program manager for the Regional Water Authority, which represents more than two dozen Sacramento area water districts.
Why rural California fears drought the most
Joe Del Bosque, a prominent farmer on the parched west side of the San Joaquin Valley, got some grim news last week from his main water supplier, the San Luis Water District. “They said we’re facing another 2014, 2015, when we had zero water supply,” said Del Bosque, who relies on the federal government’s Central Valley Project to deliver the water he needs to grow almonds, cantaloupes and other crops on about 2,000 acres (809 hectares). Last storm left Del Bosque feeling just barely better about 2021. “While everybody down here is very grateful to have this rain… I’m not sure it’s going to take us out of the drought,” he said. “This water is going to tide us over until March, when we plant,” he said. But to keep those crops going through the rest of the season, “we’ll certainly need more.”
Fears of another big drought intensify the further one gets from California’s population centers. While urban Californians endured the last drought by watching their lawns go brown, their rural counterparts measured the impact in lost dollars and jobs. UC Davis researchers found that hundreds of thousands of acres of land went fallow during the drought, erasing billions in farm income. Farmworkers saw their livelihoods suffer.
Farmers who get water from the Central Valley Project or its state counterpart, the State Water Project, are nervous about having those supplies dwindle as they did during the drought. Del Bosque, for instance, wound up buying water on the open market from other farmers to keep his crops alive. The water cost him four times what he’d normally pay the federal government – prices that aren’t sustainable over the long haul. “That takes a lot of crops off the table,” he said.
Despite being officially over since spring 2017, the effects of drought are still being felt. The drought has left water supplies in much of the San Joaquin Valley in desperate shape, even after it officially ended.
During the drought, Valley farmers pumped the equivalent of seven Shasta Lakes worth of groundwater to irrigate their crops, worsening a crisis that was decades in the making. Community wells went dry, forcing some poor towns to import bottled water, and areas of the Valley floor crumbled because of the excessive pumping.
To remedy that, former Gov. Jerry Brown signed a law to restrict groundwater pumping. The law requires newly-formed regional groundwater agencies to restore supplies to 2015 levels by 2040.
It’s a stunningly difficult task. Much of the Valley’s aquifers are considered “critically overdrafted,” according to state officials. The Public Policy Institute of California has predicted that at least 535,000 acres (more than 216,000 hectares) of agricultural land in the Valley will have to be permanently idled to comply with the reduction in pumping. That’s about 10% of the Valley’s farmland and could economically devastate one of the most impoverished regions of the state.
But instead of throttling back, farmers are under pressure to pump even harder in light of back-to-back dry winters.
The latest rains staved off “what likely would have been one of the top five driest years ever recorded”, said Jason Phillips, chief executive of the Friant Water Authority. The Friant water district stretches from Fresno to Bakersfield. However, “we’re nowhere near out of the woods relative to getting to normal,” he said, and unless conditions improve markedly, “there will be a lot of groundwater pumping to support the Valley’s cities and farms,” he added.
“Conditions are slightly better than last year”
Despite still being below average, conditions are slightly better than they were at this point last year. The storms that recently came through California brought some notable snowpack increases, however, it was not enough to bring numbers up to average. “Our water supply outlook is looking a lot better compared to where we were last week,” said Sean DeGuzman, Chief of Department of Water Resources’ Snow Surveys and Water Supply Forecasting Section.
La Nina weather systems like the one California is currently experiencing, typically pushes a lot of storm weather into the Pacific Northwest and British Colombia. Some of that weather can also impact northern California, which is why the northern snowpack is outpacing the southern sierras. As one of the wettest months of the year, February still has the potential to help make up some of the deficit.
“For the first three months of the water year – which were October, November, and December – precipitation statewide was only 39 percent of average,” DeGuzman noted. “To make up for those early dry months we’ll need multiple days of above-average precipitation. At this point, it looks like we’re just going to continue to be chasing average conditions for the foreseeable future.”
Some complementary data:
For the record, the situation of the Seasonal Drought Outlook for the United States as of December 17, 2020
Sources: sacbee.com, agnetwest.com