From Ducks Unlimited – Before Californians built a network of levees and dams to keep cities from flooding, the rivers that formed the Central Valley each winter would spill out of their channels. In the wettest years, they’d flood to form a massive inland sea that stretched hundreds of miles from Redding to Bakersfield. In wet winters such as this one, those rivers keep trying to form that massive seasonal wetland again, testing the strength of the levees that protect communities built on the state’s floodplains. Along two of the state’s most flood-prone rivers, Ducks Unlimited has been working to create wetlands that use those natural flood patterns to create vital habitat for waterbirds and wildlife. The projects highlight why Californians should look to wetland expansion as one of the solutions to help reduce the risks from future floods. (more)
From The Merced Sun-Star – The snowpack in the Sierra Nevada Mountains has reached record-breaking levels thanks to the deluge of snow smashing California this week. According to data from the California Department of Water Resources (CDWR), the Southern Sierras-from San Joaquin and Mono counties to Kern county-currently have a snowpack 257 percent greater than the average for this time of year, and 247 percent larger than is average for the usual snowpack peak on April 1. Central Sierra and Northern Sierra also have hugely inflated snowpacks, at 218 percent and 168 percent of the average for early March, respectively. TOP VIDEOS Top Videos 01:20 01:30 Merced courthouse named after legal scholar and civil rights attorney The Sierra Nevada Mountains stretch around 400 miles from Northern California southwards to the Great Basin. They have been buffeted by snowstorms as a result of the atmospheric river systems plowing eastwards from the Pacific Ocean, leaving thousands of people without power. “As of this weekend, the Southern Sierra now appears to have largest snowpack in recorded history (as measured by snow water equivalent, or SWE). Not just for the calendar date, but for *any* date!” tweeted Daniel Swain, a climate scientist at UCLA and the Nature Conservancy. (more)
From The Washington Times – Dangerous flooding could occur as heavy rain falls on snowpack in central California’s coastal range and in the foothills of the Sierra Nevada. A powerful atmospheric river — a fire hose of deep tropical moisture from the Central Pacific Ocean — is bringing life-threatening flooding and avalanche risks to waterlogged and snow-laden California, forcing evacuations as a storm delivers more mountain snowfall and heavy rain. The National Weather Service declared a “flash flooding emergency” — its most dire flooding alert — Friday morning in Tulare County, southeast of Fresno in the southern Central Valley, as heavy rain fell and rapidly melted snowpack in the lower Sierra Nevada. Authorities urged residents to seek higher ground. (more)
From The Los Angeles Times – With back-to-back storms to hit California in the coming days, state officials are scrambling to make strategic releases from key reservoirs in hopes of preventing a repeat of the flooding that killed nearly two dozen people in January. At least 10 rivers are forecast to overflow from the incoming “Pineapple Express” storm, which is expected to drop warm, heavy, snow-melting rain as it moves from the Central Coast toward the southern Sierra beginning Thursday night into Saturday. Among them are rivers that flooded at the start of the year, when nine atmospheric river storms pummeled the state. The waterways include the Cosumnes River near Sacramento, where more than a dozen levee breaches sent floodwaters onto roadways and low-lying areas, trapping drivers and contributing to at least three deaths along Highway 99. (more)
From Yahoo News – Californians are bracing for the arrival of more atmospheric rivers over the coming weeks that could dump rain on the state’s massive snowpack and dramatically increase the risk of flooding. With snowpack levels already near all-time highs, cold temperatures in the state have begun moderating in recent days, and there is a roughly 20% chance of warmer atmospheric river rains later this month. (more)
From The Mercury News – Key part of state water supply was 22% full 16 months ago, now is 65% full. One of the best places to see how dramatically big storms this winter have changed California’s water picture is three hours north of the Bay Area in the foothills east of Sacramento Valley. There, Lake Oroville, the second-largest reservoir in California and a key component of the state’s water system, has undergone a breathtaking transformation. Sixteen months ago, the reservoir was so parched from severe drought that it was just 22% full. For the first time since it opened in 1967, its power plant had shut down because there wasn’t enough water to spin the turbines and generate electricity. Now Oroville reservoir is 65% full. Since its lowest point on Sept. 30, 2021, the massive lake’s level has risen 182 feet, boosted by nine atmospheric river storms in January. (more)
The Delta Stewardship Council’s Delta Plan calls for 60,000 – 80,000 acres of restored diverse habitats in the estuary, which, if completed, would be over 100 square miles. Other agencies and initiatives have also set restoration goals for the Delta, such as the biological opinions and the voluntary agreements.
In the last decade, the Department of Water Resources has made substantial progress in getting restoration projects on the ground. Currently, the Department has 36,600 acres of restoration underway, of which 28,000 acres are either completed or under construction and another 8,500 acres is in planning that would be completed by 2030.
However, at January’s Delta Stewardship Council meeting, DWRs’ Chief of the Division of Multi-Benefit Initiatives Steve Rothert told the Council, ““If we roughly average the pace of restoration that we’ve been managing over the last couple of decades, it’s about 1,500 acres a year; so to achieve the 60 to 80,000 acre restoration goal at that pace, it would take 40 to 50 years.”
However, there is some good news. The habitat restoration projects that are being completed are starting to connect up with other completed projects. One example is the Big Notch project at the Fremont Weir, which broke ground in June of 2022.
“In the heart of our flood control system, we’re modifying a hundred year old flood control system to be friendlier for fish and to create seasonal floodplain habitat that’s desperately needed,” said DWR Program Manager Charlotte Biggs. “The project will help achieve inundation target for the Yolo Bypass.” Importantly, the Big Notch project connects down to the Cache Slough where tidal wetlands are being restored. “As we create more connectivity through the bypass, we are eliminating those fish passage barriers, so that restoration in Cache Slough is going to be creating the habitat, the food source, and the shelter to help the fish survive through those areas.”
From Reuters – When devastating floods swept California last month, the community of Grayson – a town of 1,300 people tucked between almond orchards and dairy farms where the San Joaquin and Tuolumne rivers converge – survived without major damage. In the minds of some townspeople and experts, that was thanks partly to the 2,100 acres (850 hectares) of former farmland just across the San Joaquin that have been largely restored to a natural floodplain. Advocates for floodplain restoration say it can help solve California’s dual dangers of flooding and drought, replenishing groundwater for future drought relief while protecting towns from the catastrophic flooding that scientists predict will come with climate change. Restoration also improves wildlife habitat. (more)
From USACE Sacramento District – The U.S. Army Corps of Engineers Sacramento District awarded a $27.575 million construction contract on January 20, 2023, to Maloney Odin Joint Venture of Novato, for more than 2.6 miles of levee improvements at five locations along the Sacramento River East Levee between the I Street Bridge and just south of the town of Freeport. Work is scheduled to begin this spring and is expected to be complete in December 2023. USACE is planning to host an informational meeting in March to discuss what this construction work will look like, including trail access, haul routes, and staging areas. Details for this meeting are still being finalized and will be posted to www.sacleveeupgrades.com prior to the meeting. This is the fourth, and should be final, major construction contract to address seepage and stability concerns with the levee. Last year, construction crews completed two miles of levee improvements in the Pocket neighborhood from Surfside Way to Sump 132 at the Pocket Canal. In 2020 and 2021, nearly five miles of levee improvements were made. (more)
Most snow since 1995; hopes increase for an end to California drought, but flood concerns remain
From The Mercury News –The statewide Sierra Nevada snowpack — the source of nearly one-third of California’s water supply — is at its highest level since 1995, boosting hopes that an end to the drought is near, but also raising concerns that a few warm spring storms could melt it too early and trigger major flooding. The huge bounty is the fourth largest statewide since 1950, when consistent statewide records began, according to a Bay Area News Group analysis of historical data. Only 1952 (267% of average) and 1969 (230%), and 1995 (208%) had larger amounts on Feb. 1. In a few places, like Highland Meadow in Alpine County, the snowpack is the largest in recorded history. (more)
