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Sierra Nevada Snowpack Feb 27 2020 California DWR-WNN

California’s Winter: Wet Times, Dry Times and Water Supplies

After a wet and snowy start, California’s winter has gone bust. The 2019-2020 water year started off with robust precipitation after a series of storms in November and early December 2019.

But the new year has not been as bountiful. Dry conditions in January and February added little to the Sierra Nevada snowpack.

NASA-NWS-Sierra Snowpack Comparison - Water News Network Feb 2020

Left: 2019, Right: 2020. Sierra Nevada snowpack is below normal for this time of year, at about 58% statewide. Graphic: NASA/National Weather Service via NWS Sacramento

Drought-resilient water supplies through diversification

Due to California’s climatological variability, including periods of drought, the Water Authority and its 24 member agencies have diversified water supply sources. Those successful efforts ensure supply reliability for the region’s 3.3 million residents and its $245 billion regional economy.

“Based on current supply levels, the Water Authority and its 24 member agencies will meet anticipated demands through a combination of drought-resilient local and regional water resources,” said Goldy Herbon, Water Authority senior water resources specialist.

Water supplies will meet demand

Herbon said the Claude “Bud” Lewis Carlsbad Desalination Plant, conserved agricultural water transfers, savings from canal lining projects and continued water-use efficiency measures are among the reasons the region’s water supply will meet demand.

The multi-decade water supply diversification plan, along with major infrastructure improvements and forward-thinking policies, also promote fiscal and environmental responsibility.

“A comparison of the snowpack across the Sierra-Cascade range over the past 6 years shows the true variability of a California wet season. While numbers are similar to the 2017-2018 winter, snow did extend into somewhat lower elevations back then.” NWS Sacramento, February 26, 2020

Dry times in Northern California

While rainfall totals have been closer to average in most of Northern California, downtown Sacramento and downtown San Francisco did not receive any precipitation in February, according to the National Weather Service. The last time San Francisco saw a dry February was in 1864, according to the NWS.

NWS Sacramento Dry February 2020

Rainfall above historical average in San Diego

Southern California is faring better, with rainfall at 125% of the historical average at Lindbergh Field in San Diego.

Most major California reservoirs are at or above the historical averages for late-February.

The state’s largest six reservoirs currently hold between 92% (Oroville) and 132% (Melones) of their historical averages for February 26. Lake Shasta, California’s largest surface reservoir, is 107% of its historical average and sits at 78% of capacity, according to the California Department of Water Resources.

Water Supply-Major Reservoirs-DWR-WNN Feb 2020

California’s largest six reservoirs hold between 92% and 132% of their historical averages for Feb. 27. Lake Shasta, California’s largest surface reservoir, is at 107% of its historical average and is at 78% of capacity. Graphic: California Department of Water Resources

The Department of Water Resources February 27 conducted the third manual snow survey of 2020 at Phillips Station. The manual survey recorded 29 inches of snow depth and a snow water equivalent of 11.5 inches, which is 47% of the March average for this location, according to a DWR news release. The snow water equivalent measures the amount of water contained in the snowpack, which provides a more accurate forecast of spring runoff.

Spring storms could boost snowpack

“Right now, 2020 is on track to be a below-average year but we could still see large storms in March and April that will improve the current snowpack,” said Sean de Guzman, chief of DWR’s Snow Surveys and Water Supply Forecasting Section. “While periods of dry conditions are expected in California, climate change has made them more unpredictable and extreme which is why we must always use the water we have wisely.”

March April May precipitation 20-Feb-2020 NWS CPC

The seasonal outlook for March, April, and May sees below-normal chances for a wet period across California and the Southwest U.S. while most areas are favored to be warmer than usual. Graphic: National Weather Service Climate Prediction Center

Looking ahead, the National Weather Service Climate Prediction Center forecast favors above-normal temperatures and below-normal precipitation through May for most of California.

NWS CPC Spring 2020 temperature forecast-WNN

The National Weather Service Climate Prediction Center forecast favors above-normal temperatures and below normal precipitation through May for most of California. Graphic: National Weather Service Climate Prediction Center

One Tunnel, Same Distrust

State water officials offered an early look at the downsized California WaterFix project earlier this month, and conservationists and far-traveling indigenous tribes say they still believe it has the potential to permanently alter life in and around the Delta.

The old version of California WaterFix, better known as the “twin tunnels,” was opposed by virtually every major environmental organization in the state, as well as fishing alliances, Delta businesses and groups concerned with the cultural and historic resources from Freeport to Walnut Grove.

Some in the Sierra Still Optimistic Despite Below-Average Snowpack

Last month, the state’s snow survey team saw snow levels just shy of average and on Thursday the trend continued downward.

“Seventy-nine percent of an average February and 58% of the April 1 average here at this location,” said Sean de Guzman, chief of the Department of Water Resources’ Snow Surveys and Water Supply Forecasting Section.

Along with measurements taken at the station near Echo Summit, measurements at 260 other locations indicate the snowpack is below average.

Opinion: California’s Water Department Must Face the Reality of Climate Change and Diverse Needs

As we enter a new decade, California faces increasing environmental challenges caused by climate change, creating an uncertain future for our water resources. We need bold leadership to address these impacts. It is time for California’s Department of Water Resources to implement water policy for the state that shores up our precious waterways and diversifies water supplies in the face of these imminent threats.

Aging Oroville Dam Spillway Gates Draw Concern

Despite increased maintenance of Oroville Dam since the spillway fell apart in February 2017, members of the community-led Oroville Dam Ad Hoc Group have expressed concern about the age and wear of mechanics within the spillway’s main gates, citing similar failures on dams of the same era.

The Department of Water Resources convened a meeting Nov. 13 of the Oroville Dam Ad Hoc Group — an organization comprised of local elected officials and stakeholders appointed by state Sen. Jim Nielsen (R-Tehama) and Assemblyman James Gallagher (R-Yuba City) — as part of the Oroville Dam Safety Comprehensive Needs Assessment that was initiated by the DWR after the spillway crumbled.

Yuba Water Agency, DWR Launch Research To Enhance Reservoir Operations

Yuba Water Agency launched an initiative with the California Department of Water Resources (DWR) and University of California San Diego’s Scripps Institution of Oceanography to improve storm and runoff forecasting, and significantly reduce flood risk though enhanced operations of New Bullards Bar and Oroville dams. This research will supply information needed for the U.S. Army Corps of Engineers to update the 1970’s-era water control manuals, which dictate the storm-season operations of both reservoirs. Yuba Water’s goal is to have a new water control manual approved about the same time the agency completes construction of a new, planned secondary spillway at its New Bullards Bar Dam, estimated for completion in 2024.

Spillway Could Be Used Next Week, DWR Says

The newly-renovated Oroville Dam spillway could be used as early as next week, the state Department of Water Resources said Tuesday. DWR is “closely monitoring Oroville reservoir levels and current forecasts,” the water agency said in a press release. With storms forecast in the Feather River basin, DWR said it is taking steps to prepare for use of the main spillway by the first week of April. Although the state water agency said the spillway was usable in October 2017 if needed, water has not flowed in significant amounts since the spillway crisis in February 2017, when a hole in the enormous concrete structure led to use of the emergency spillway concrete weir for the first time in history and eventually the evacuation of more than 188,000 downstream residents.

DWR Set To Appeal Oroville Funding Denials

California’s state water agency is set to appeal a federal determination that some of the Oroville Dam’s reconstruction costs are ineligible for reimbursement. The Federal Emergency Management Agency last week approved an additional $205 million for the project, on top of the $128.4 million it sent last year, according to the state Department of Water Resources.

DWR Set To Appeal Oroville Funding Denials

California’s state water agency is set to appeal a federal determination that some of the Oroville Dam’s reconstruction costs are ineligible for reimbursement. The Federal Emergency Management Agency last week approved an additional $205 million for the project, on top of the $128.4 million it sent last year, according to the state Department of Water Resources.

Senate Bill 204 Increases WaterFix Oversight

During a town hall meeting in November 2017, the Delta Caucus co-chairs state Sen. Bill Todd (D-Napa) and Assemblymember Jim Frazier (D-Discovery Bay) opined for more legislative oversight pertaining to the California WaterFix project. Last week they took a step in that direction. Todd introduced Senate Bill (SB) 204, which would require the Department of Water Resources (DWR) and the Delta Conveyance, Design and Construction Authority (DCDCA) to submit information about pending State Water Project contracts to the legislature for public review prior to those agencies moving forward with work on the Delta Tunnels.