A judge has ordered the Los Angeles Department of Water and Power to continue providing historic quantities of irrigation water to lessees of its pasturelands east of Yosemite, despite the agency’s assertion that climate change is making water resources in the Sierra Nevada watershed increasingly unreliable.
Sierra snowpack is so vital to California as it provides one third of the state’s water supply and it seems more and more lately we are seeing this dwindle. You can see from 2002 to 2011 60% of the time the Sierra snowpack was 100% or better, a pretty good trend.
Precipitation is below average in California for the current water year. Despite recent storms that increased the statewide Sierra Nevada snowpack to 70% of average to date, the state is experiencing its second consecutive below average year for rain and snow.
Precipitation is below average in California for the current water year. Despite recent storms that increased the statewide Sierra Nevada snowpack to 70% of average to date, the state is experiencing its second consecutive below average year for rain and snow. The water year starts on October 1 and ends September 30.
The Department of Water Resources Feb. 3 conducted the second manual snow survey of the season at Phillips Station. The manual survey recorded 63 inches of snow depth and a snow water equivalent, or SWE, of 17 inches, which is 93% of average for that location, according to the DWR. The SWE measures the amount of water contained in the snowpack and is a key component of DWR’s water supply forecast.
“The recent blast of winter weather was a welcome sight, but it was not enough to offset this winter’s dry start,” said DWR Director Karla Nemeth. “While there is still a chance we will see additional storms in the coming weeks, the Department and other state agencies are preparing for the potential for a second consecutive year of dry conditions.”
Below normal precipitation is favored throughout most of the southern tier of the United States in late February to early March, according to the National Weather Service Climate Prediction Center. La Niña conditions remain over the Pacific Ocean.
Statewide snow survey measurements reflect those dry conditions. Measurements from DWR’s electronic snow survey stations indicate that statewide the snowpack’s SWE is 12.5 inches, or 70% of the February 3 average, and 45% of the April 1 average. April 1 is typically when California’s snowpack is the deepest and has the highest SWE.
“The recent atmospheric storms have brought rain and snow to the northern Sierra Nevada, but conditions are still well below normal,” said Goldy Herbon, San Diego County Water Authority senior resources specialist.
Following last year’s below average water year, northern California is now experiencing its second straight water year of below average precipitation.
How it started.
How it's going.Season-to-date snowfall through January 23 vs February 4.#CAwx #CAsnow ❄️☃️🏂🌨️ pic.twitter.com/UOvjEmxa5k
— NWS Sacramento (@NWSSacramento) February 4, 2021
Another source of the state’s water supply, the Colorado River Basin, isn’t faring much better. The water year 2021 precipitation at the end of January for the Colorado River Basin is 66% of normal, according to the U.S. Bureau of Reclamation.
Precipitation totals to date are behind historical averages for two of the main sources of San Diego County’s supply, with two months to go in the winter season but, a couple of atmospheric rivers can change that quickly.
“The San Diego region will have a plentiful and reliable source of water due to actions taken by the Water Authority and its 24 member agencies to diversify the water supply,” said Herbon. “Continuing efforts to expand supply sources, including desalination, water reuse, and recycling, will ensure that the water needs are met for the region’s 3.3 million people and its $245 billion economy.”
Fall 2020 was extremely dry, especially in the Sierra Nevada, and follows last year’s below-average snow and precipitation, according to the DWR. With only a couple months remaining in California’s traditional wet season, DWR officials say Californians should look at ways to reduce water use at home.
Statewide Sierra Nevada snowpack is 71% of average for February 4, 2021. Graphic: California Department of Water Resources
California’s water picture is heading in two different directions.
A major storm last week and a more modest system Tuesday continued to boost the Sierra Nevada snowpack, the source of one-third of the state’s water supply, in promising ways. But the Bay Area and most cities across Northern California remain stuck in one of the worst two-year rainfall deficits seen since the 1849 Gold Rush, increasing the risk of water restrictions and dry wildfire conditions locally next summer.
This updates a post from December on the likelihood of California entering a second dry year. Normally, a second dry year brings drought operations for California’s overall water system operations.
Today, it is even likelier that California is entering a multi-year drought.
Precipitation conditions have improved somewhat with a nice atmospheric river this last week, but remain 51% of average for this time of year for the Sacramento Valley. (San Joaquin and Tulare basins are 61% and 47% of historical seasonal average precipitation so far.) Snowpack has improved somewhat with very recent storms, but is about as scarce as the precipitation.
California’s increasingly volatile warming climate is making droughts more intense, and complicating water management. A just-launched commodity futures market for the state’s water provides a new tool for farmers, municipalities and other interested parties to ensure against water price shocks arising from drought-fueled shortages.
Taking a Wall Street approach to an essential natural resource has prompted both fear and hype. Will California experience a new Gold Rush in water? Will speculation boost the cost of water? Perhaps both the fear and the hype are unwarranted.
A dry start to California’s water year is reflected in the season’s first snow survey of the Sierra Nevada snowpack. The statewide snowpack is 52% of average for Dec. 30. On average, the Sierra snowpack supplies about 30% of California’s water needs.
The California Department of Water Resources manual survey at Phillips Station recorded 30.5 inches of snow depth and a snow water equivalent of 10.5 inches, which is 93% of the January 1 average at that location, according to DWR officials. The snow water equivalent,or SWE, measures the amount of water contained in the snowpack and is a key component of DWR’s water supply forecast.
While the Phillips Station measurement was positive, DWR’s electronic readings from 130 stations placed throughout California show the statewide snowpack’s SWE is 5 inches, or 52% of the December 30 average.
“The snow survey results reflect California’s dry start to the water year and provide an important reminder that our state’s variable weather conditions are made more extreme by climate change,” said DWR Director Karla Nemeth. “We still have several months left to bring us up to average, but we should prepare now for extended dry conditions. The Department, along with other state agencies and local water districts, is prepared to support communities should conditions remain dry.”
“The first snowpack survey of the water year points to California’s climate variability, which is why a diverse water portfolio is needed to provide a reliable supply,” said Goldy Herbon, San Diego County Water Authority senior water resources specialist. “The Water Authority and its 24 member agencies have successfully diversified water sources, and continue to expand those sources, to ensure our supply meets the needs of the region’s 3.3 million people and its $245 billion economy.”
The supply sources include water from the Claude “Bud” Lewis Carlsbad Desalination Plant, where ten workers volunteered to live on-site in 2020 to keep the water flowing during the coronavirus pandemic.
When the Sierra Nevada snowpack melts, it feeds into rivers and is stored in reservoirs across California. Reservoirs are tapped as needed during the dry months. However, state officials again said that climate change is affecting California’s snowpack, as more precipitation falls as rain and less as snow. And they urged Californians to make water conservation a “way of life.”
“Today’s survey brought a first glimpse of how the state’s snowpack is shaping up, but there is a lot of winter still ahead,” said Sean de Guzman, chief of DWR’s Snow Surveys and Water Supply Forecasting Section. “While the dry conditions during late summer and fall have led to a below average snowpack, it is still encouraging to have the amount of snow we already have with two of the three typically wettest months still to come.”
DWR conducts five snow surveys at Phillips Station each winter near the first of each month, January through April and, if necessary, May. Guzman said the next survey is scheduled for February 2.
Sean De Guzman (R), chief of the California Department of Water Resources Snow Surveys and Water Supply Forecasting Section, and Jeremy Hill, DWR water resources engineer, conduct the first snow survey of the 2021 season at Phillips Station in the Sierra Nevada. Photo: Kelly M. Grow/DWR
A month into California’s peak storm season, the lack of wet weather is beginning to weigh on the state’s water supply.
The snowpack in the Sierra and southern Cascades, which provides as much as a third of the water used by California cities and farms, is about 55% of average for this time of year. It hasn’t been this low at this time since 2017, when the state was emerging from a five-year drought.
The Water News Network is San Diego County’s source for water news and information.
