Tag Archive for: Water Supply

Sierra Nevada Snowpack: One of the Largest on Record

Following three consecutive years of drought in California, the Sierra Nevada snowpack is one of the most bountiful in more than 40 years. While the snowpack and snow water equivalent is great news for water supply, there are concerns the record snowpack could create flooding issues.

The California Department of Water Resources electronic readings from 130 snow sensors placed throughout the state indicate the statewide Sierra Nevada snowpack’s snow water equivalent is 61.1 inches, or 237% of average for April 3. The snow water equivalent measures the amount of water contained in the snowpack and is a key component of DWR’s water supply forecast.

Sierra Nevada snowpack

This year’s April result from the statewide snow sensor network is higher than any other reading since the snow sensor network was established in the mid-1980s. Before the network was established, the 1983 April 1 statewide summary from manual snow course measurements was 227% of average. The 1952 April 1 statewide summary for snow course measurements was 237% of average.

“This year’s severe storms and flooding is the latest example that California’s climate is becoming more extreme,” said DWR Director Karla Nemeth after the April 3 snow survey at Phillips Station in the Sierra Nevada. Photo: Fred Greaves/California DWR

“California’s climate is becoming more extreme”

“This year’s severe storms and flooding is the latest example that California’s climate is becoming more extreme,” said DWR Director Karla Nemeth. “After the driest three years on record and devastating drought impacts to communities across the state, DWR has rapidly shifted to flood response and forecasting for the upcoming snowmelt. We have provided flood assistance to many communities who just a few months ago were facing severe drought impacts.”

Just as the drought years demonstrated that California’s water system is facing new climate challenges, this year is showing how the state’s flood infrastructure will continue to face climate-driven challenges for moving and storing as much of these flood water as possible.

Sierra Nevada snowpack-snow survey-DWR-

“This year’s result will go down as one of the largest snowpack years on record in California,” said Sean de Guzman, manager of DWR’s Snow Surveys and Water Supply Forecasting Unit. (R-to-L: de Guzman, Jacob Kollen, Water Resources Engineer in Snow Surveys and Water Supply Forecasting Unit, and Jordan Thoennes, Water Resources Engineer in Snow Surveys and Water Supply Forecasting Unit.) Photo: Kenneth James/California DWR

“One of the largest snowpack years on record”

“This year’s result will go down as one of the largest snowpack years on record in California,” said Sean de Guzman, manager of DWR’s Snow Surveys and Water Supply Forecasting Unit. “While 1952’s snow course measurements showed a similar result, there were fewer snow courses at that time, making it difficult to compare to today’s results. Because additional snow courses were added over the years, it is difficult to compare results accurately across the decades with precision, but this year’s snowpack is definitely one of the biggest the state has seen since the 1950s.”

Sierra Nevada-snowpack-April 2023-DWR

Snowpack varies by region

For California’s snow course measurements, only 1952, 1969 and 1983 recorded statewide results above 200% of the April 1 average. While above average across the state this year, snowpack varies considerably by region. The Southern Sierra snowpack is currently 300% of its April 1 average and the Central Sierra is at 237% of its April 1 average. However, the critical Northern Sierra, where the state’s largest surface water reservoirs are located, is at 192% of its April 1 average.

Flooding and spring snowmelt

The size and distribution of this year’s snowpack is also posing severe flood risk to areas of the state, especially the Southern San Joaquin Valley. DWR’s State-Federal Flood Operations Center (FOC) is supporting emergency response in the Tulare Lake Basin and Lower San Joaquin River by providing flood fight specialists to support ongoing flood response activities and by providing longer-term advanced planning activities.

The FOC and DWR’s Snow Surveys and Water Supply Forecasting Unit are helping local agencies plan for the spring snowmelt season by providing hydraulic and hydrologic modeling and snowmelt forecasts specific to the Tulare Lake Basin that are informed by DWR’s snowmelt forecasting tools, including Airborne Snow Observatory (ASO) surveys.

Storms this year have caused impacts across the state including flooding in the community of Pajaro and communities in Sacramento, Tulare, and Merced counties. The FOC has helped Californians by providing over 1.4 million sandbags, over 1 million square feet of plastic sheeting, and over 9,000 feet of reinforcing muscle wall, across the state since January.

State Water Project deliveries increased

On March 24, DWR announced an increase in the forecasted State Water Project deliveries to 75%, up from 35% announced in February, due to the improvement in the state’s water supplies. Governor Gavin Newsom has rolled back some drought emergency provisions that are no longer needed due to improved water conditions, while maintaining other measures that continue building up long-term water resilience and that support regions and communities still facing water supply challenges.

Sierra Nevada Snowpack-April 2023-Reservoir conditions

Water supply challenges

While winter storms have helped the snowpack and reservoirs, groundwater basins are much slower to recover. Many rural areas are still experiencing water supply challenges, especially communities that rely on groundwater supplies which have been depleted due to prolonged drought.

Water conservation ‘a way of life’

Long-term drought conditions in the Colorado River Basin will also continue to impact the water supply for millions of Californians. The state continues to encourage Californians to make water conservation a way of life as more swings between wet and dry conditions will continue in the future. The San Diego County Water Authority and its 24 member agencies provide rebates and programs to encourage water conservation.

Given the size of this year’s snowpack with more snow in the forecast, DWR anticipates conducting a May snow survey at Phillips Station. That is tentatively scheduled for May 1.

Turning Seawater into Drinking Water

The power and technology behind the Claude “Bud” Lewis Carlsbad Desalination Plant, which turns seawater into drinking water, is described in this video report from Reporter Trason Bragg.

The Carlsbad Desalination Plant is the largest, most technologically advanced and energy-efficient desalination plant in the nation, and it has produced more than 100 billion gallons of drinking water for San Diego County since operations began in December 2015.

Join Us for a Rate Study Workshop on April 19, 2023

Chula Vista – Sweetwater Authority is hosting a Rate Study Workshop -Technical Session on April 19, 2023 from 3:00 p.m. – 4:00 p.m. This in-person workshop is being held at the Authority’s Administration Building located at 505 Garrett Avenue in Chula Vista.

sea water-seawater desalination-desalination-Carlsbad Desalination Plant-Trason Bragg

Turning Seawater into Drinking Water

The power and technology behind the Claude “Bud” Lewis Carlsbad Desalination Plant, which turns seawater into drinking water, is described in this video report from Reporter Trason Bragg.

The Carlsbad Desalination Plant is the largest, most technologically advanced and energy-efficient desalination plant in the nation, and it has produced more than 100 billion gallons of drinking water for San Diego County since operations began in December 2015.

Seawater into drinking water

New intake and discharge facilities

The new intake and discharge facilities at the Carlsbad Desalination Plant will ensure the plant continues to meet California’s stringent Ocean Plan standards for protecting marine life. Work started in January 2023 and the new facilities are anticipated to be operational by December 2024. Except for a planned plant outage required near the end of the project to connect the new facilities to the existing intake system, construction is not expected to impact water production.

100 billion gallons-reverse osmosis-seawater desalination

Reverse osmosis is the heart of the Carlsbad Desalination Plant. During this process, dissolved salt and other minerals are separated from the water, making it fit for consumption. This reverse osmosis building contains more than 2,000 pressure vessels housing more than 16,000 reverse osmosis membranes. Photo: San Diego County Water Authority

Reclamation Increases Central Valley Project 2023 Water Supply Allocations

The Bureau of Reclamation March 28, announced an increase in Central Valley Project 2023 water supply allocations. After below average precipitation in February, Reclamation announced a conservative initial water supply allocation for the CVP on Feb. 22. Additional atmospheric river systems have since boosted hydrological conditions and storage volumes, allowing for a more robust water supply allocation.

Since making initial allocations last month, Shasta Reservoir, the cornerstone of the Central Valley Project, has increased from 59% to 81%, and San Luis Reservoir, the largest reservoir south-of-Delta, from 64% to 97%. Record-breaking snowpack conditions currently exist in the Southern Sierra coupled with significant snowpack in the Central Sierra and Northern Sierra/Trinity.

Supply Allocation-Central Valley Project-Bureau of Reclamation

Reclamation Increases Central Valley Project 2023 Water Supply Allocations

The Bureau of Reclamation March 28, announced an increase in Central Valley Project 2023 water supply allocations. After below average precipitation in February, Reclamation announced a conservative initial water supply allocation for the CVP on Feb. 22. Additional atmospheric river systems have since boosted hydrological conditions and storage volumes, allowing for a more robust water supply allocation.

Since making initial allocations last month, Shasta Reservoir, the cornerstone of the Central Valley Project, has increased from 59% to 81%, and San Luis Reservoir, the largest reservoir south-of-Delta, from 64% to 97%. Record-breaking snowpack conditions currently exist in the Southern Sierra coupled with significant snowpack in the Central Sierra and Northern Sierra/Trinity.

2023 Central Valley Project supply allocations increased

Based on current hydrology and forecasting, Reclamation is announcing the following increases to CVP water supply allocations:

North-of-Delta Contractors

  • Irrigation water service and repayment contractors north-of-Delta are increased to 80% from 35% of their contract total.
  • Municipal and industrial water service and repayment contractors north-of-Delta are increased to 100% from 75% of their historic use.

South-of-Delta Contractors

  • Irrigation water service and repayment contractors south-of-Delta are increased to 80% from 35% of their contract total.
  • M&I water service and repayment contractors south-of-Delta are increased to 100% from 75% of their historical use.

Friant Division Contractors

  • Friant Division contractors’ water supply is delivered from Millerton Reservoir on the upper San Joaquin River and categorized by Class 1 and Class 2. The first 800,000 acre-feet of available water supply is considered Class 1; Class 2 is considered the next amount of available water supply up to 1.4 million acre-feet. Class 1 remains at 100% and Class 2 was previously increased from 20% to 70% on March 7.

Friant Dam is currently being operated for flood control purposes; as long as these conditions exist contractors are able to take delivery of all available water from Friant Dam to the maximum extent of their respective contracts.

All other CVP water supply allocations remain the same as noted in the Feb. 22 announcement.

As the water year progresses, changes in hydrology, actions that impact operations, and opportunities to deliver additional water will influence future allocations. Reclamation will continue to monitor hydrology and may adjust basin-specific allocations if conditions warrant an update. Water supply updates and past year’s allocations are posted on Reclamation California-Great Basin Region’s website.

This Drought is Dead – Long Live the Drought

Floods and droughts are not opposites and can occur simultaneously. This occurs often in California and is especially well-illustrated this year.

Floods, droughts, and water scarcity are different. Floods are too much water at a place and time, and we would often pay to reduce the water present at that location and moment. Droughts and water scarcity represent too little water at a place and time, meaning we would often pay to increase its availability. We highlight these differences because people tend to view such conditions through an unrealistic zero-sum lens. This essay uses this year’s experience to examine how floods, drought, and water scarcity differ, can occur in the same year, and how droughts might end, but leave legacies.

This California drought is largely over. Even though there is another month left in California’s wet season, the 2020-2022 California drought is largely over. Precipitation in all major basins of California exceeds averages for the entire water year. Snowpacks are well above April 1 averages (usually about the maximum for the year). Most reservoirs have more than average volumes stored for this time of year, and many are in flood operations. Only a few very large reservoirs (relative to their average inflows) remain below historical averages (such as Trinity at 50% and New Melones at 90% of their averages).

Opinion: MMWD Must Show How Rate Hike Will Help Water Supply

The Marin Municipal Water District’s directors are on a political hot seat.

They are considering a four-year plan of raising rates, possibly as much as 20% for most customers, to right MMWD’s fiscal ship and pay for expanding the district’s storage capacity and make needed repairs.

Snow Readings Give Reprieve to Colorado River Shortage

“It’s snowing!” is how Imperial Irrigation District Water Manager Tina Shields began her hydrology report at the March 21 regular meeting. The water manager’s monthly reports have taken a turn to the positive after years of dire Lake Mead elevation readings.

Although Central California irrigates with water from different sources other than the Colorado River, the Valley’s sole source of water, Shields reported the continuous atmospheric rivers have been devastating to the Central Valley farmland with reports of flooding and washing out of ground.

“Every drought is followed by a flood,” she said. “They have had 250% above average of rain, the photos of two-story houses buried in snow and ski lifts unusable because they are covered in snow are crazy. They are actually talking about Fourth of July skiing and that fields will stay flooded for months. It is all time record breaking.”

Opinion: Western Water Crisis Solutions Inevitably End With a Lot Less for California Farms

A modest proposal for western water: Turn off the spigot to the Imperial Valley and let the farms go fallow. In return, provide a water future for Arizona, Nevada and Southern California.

Sure, there would be a price to pay. California’s Imperial Valley, which sits in the southeastern corner of the state, bordered by Arizona and Mexico, produces alfalfa, lettuce, corn and sugar beets, among other crops. It’s home to more than 300,000 head of cattle. Cutting off the water would end all of that, along with the livelihoods of the farmers and ranchers who produce it and the communities that depend on it.