A wrap-up of posts published on Maven’s Notebook this week …
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In California water news this week …
California faces a new storm threat on Sunday, adding to staggering snowfall totals
“Another storm is lining up for California starting later this weekend, arriving just days after the latest storm unloaded significant snow in the mountains and rain at lower elevations. The next round could bring drenching rain and more heavy mountain snow, especially to Northern California. Prior to the start of Thursday’s storm, the 72-hour snowfall over parts of the Sierra Nevada ranged from a little over a foot of snow in the southern areas to nearly 8 feet in the central and northern parts of the mountain range, according to ski resorts. In the past seven days, 92.5 inches of snow have fallen at the Central Sierra Snow Lab. The amount of snow is not unheard of in the Sierra Nevada, but it is excessive nonetheless and has already resulted in deadly avalanches and multiple road closures, including along the busy Interstate 80 and Donner Pass, California, area. … ” Read more from AccuWeather.
Big storms boost California water supply, but snowpack lags
“Ever since California was pummeled by a series of storms in fall and early winter, experts have said the state’s water supply is looking strong for this year. Those storms — with a potential bump from the ones hitting much of the state this week — have helped refill reservoirs and eased immediate drought worries in many parts of the state. But experts also say that a few wet storms don’t mean we’re out of the woods. That’s because this winter is a “classically climate-change-flavored one,” according to Daniel Swain, a weather and climate scientist with UC Agriculture and Natural Resources. And that’s not because it’s been a particularly dry winter, he explained. It’s because it’s the warmest winter the West has ever seen. “In the Western U.S., the snowpack is, on average, terrible,” Swain said. “It’s about as bad as it’s ever been in observed history.” … ” Read more from KQED.
Snow drought helped set the stage for deadly California avalanche, leading to unstable conditions
“A weekslong “snow drought” in Northern California’s Sierra Nevada helped set the stage for Tuesday’s deadly avalanche, after several feet of new snow fell on an earlier layer that had hardened, making it unstable and easily triggered, experts said. The new snow did not have time to bond to the earlier layer before the avalanche near Lake Tahoe killed at least eight backcountry skiers, said Craig Clements, a meteorology professor at San Jose State University, who has conducted avalanche research. Six skiers survived and rescuers were still searching for another one who was still missing on Wednesday. The group was on a three-day backcountry trek in the Sierra Nevada on Tuesday morning when they were trapped by the avalanche as a winter storm pummeled the West Coast. The dangers generally are highest in the first 24 to 48 hours after a very large snowfall, Clements said, and authorities had issued avalanche warnings. Here’s what to know. … ” Read more from the Associated Press.
State accelerates stormwater capture opportunities with 5-year groundwater recharge permits
“Just before storms began drenching parts of California this week, the State Water Resources Control Board issued the last of nine groundwater recharge permits for this wet season, bringing the total amount of water authorized for underground storage to nearly 43,000 acre-feet, or enough to supply over 128,000 households for a year. The State Water Board approved all the permit applications it received in recent months, including two 180-day and seven 5-year permits, the highest number of the longer-term permits issued for one season since they became available in 2020. Permits were granted to water districts and groundwater sustainability agencies for recharge projects in the Sacramento, San Joaquin, Shasta and Scott River watersheds. Two other 5-year permits issued in 2023 are still in effect. “As California’s climate changes and grows more extreme, every storm is a critical opportunity to capture water and replenish our aquifers before the next drought,” said board Chair E. Joaquin Esquivel. “I’m glad to see more of our partners taking advantage of our expedited process and 5-year permits, because building groundwater reserves helps communities maintain drinking water supplies when conditions turn dry.” … ” Read more from the State Water Board.
Soil health meets recharge: Lessons from the field
“As the afternoon sun burned the dense tule fog off the valley floor, a group of growers, water managers, researchers, and curious minds gathered at a Valov Brothers Farm pistachio orchard block in Tulare County. Water pulsed from a pump and spread across the orchard floor as the attendees discussed a shared question: how can we replenish groundwater resources while improving water quality? The field day brought together partners participating in a pilot research study designed to explore this question. The project examines how soil health practices like cover crops influence the impacts of on-farm recharge on conditions like nitrate leaching and water infiltration. By setting up side-by-side experiments, the project aims to generate data that growers, agencies, and researchers can use to better inform scaling recharge across the Valley. … ” Read more from Sustainable Conservation.
ILRP: Expert panel nears completion of draft recommendations: A peek inside
“The Second Statewide Agricultural Expert Panel, convened by the State Water Board to advise it on reducing nitrogen (N) contamination of groundwater through the Irrigated Lands Regulatory Program (ILRP), is drawing closer to releasing a draft report for public comment after holding a series of working group meetings in January and February 2026. During working group meetings, panelists have been provided additional information that they requested including data on farm size differences in reported N applied and crop diversity, Eric Porse and Divya Prakash of University of California Agriculture and Natural Resources (UC ANR); immobilizing soil nitrate using high carbon amendments to reduce nitrate leaching, Joji Muramoto, UC Santa Cruz, UC Cooperative Extension, and UC ANR; and gaseous N losses from specialty crops in the Central Coast, Stephanie Kortman, California State University Monterey Bay (CSUMB). Panelists spent the bulk of their working group meeting time hashing out wording and finessing details of their recommendations. … ” Continue reading from Jane Sooby at Maven’s Notebook.
CV-NPSAT: A scalable solution for groundwater contaminant modeling
“Understanding, managing, and regulating nonpoint source pollution of groundwater is a challenge for California. Nonpoint sources of groundwater pollution encompass tens to hundreds of thousands of individually managed plots, fields, and other land parcels, covering about 10 million acres in California. Models are used to assess the impacts of land management improvements on long-term outcomes at water supply wells, but scaling is an issue, as well as computational resources. The Nonpoint Source Assessment Toolbox (NPSAT) is an open-source groundwater modeling framework developed by the University of California Davis to serve as an alternative, efficient approach to standard groundwater contamination models. It evaluates the fate and transport of nonpoint source (NPS) contaminants (such as nitrate and salts) leaching to groundwater from agricultural, urban, and natural land uses, in irrigation, public, and domestic supply wells through “on-the-fly” evaluations of user-defined nonpoint source contaminant leaching scenarios. … ” Read more from the State Water Board.
McNerney joins with Delta enviros & State Water Contractors on major bill to protect CA’s water
“State Sen. Jerry McNerney, D-Pleasanton, today announced the introduction of SB 872, groundbreaking legislation that would help protect California’s primary water source for decades to come. Supported by environmentalists and State Water Contractors that have often been at odds over water use, SB 872 would safeguard both the Sacramento-San Joaquin River Delta and the State Water Project (SWP). “Historically, California’s water wars have pitted North against South, the environment versus agriculture,” said Sen. McNerney, who is co-chair of the Delta Caucus and whose district includes the heart of the Delta. “SB 872 is a commonsense solution that brings traditional adversaries together to support vital water projects that will protect California’s water and the Delta, while also benefitting the entire state.” … ” Read more from Senator Jerry McNerney.
National Academies study: New and notable recommendations for protecting at-risk fish from water diversions in the Bay-Delta system
“In 2021, California suffered a severe drought and the hottest summer then on record. Water was beyond scarce. It was brutal for the fish, farmers and others who depend on flows in the San Francisco Bay-Delta watershed, a system that spans hundreds of miles from mountain headwaters to the confluence of California’s two longest rivers, the Sacramento and the San Joaquin. But that year also saw the beginnings of a new National Academies study to help California’s imperiled salmon, smelt and sturgeon survive people’s relentless water diversions from the Bay-Delta system. Supplying water without sacrificing fish is a “massive, high stakes balancing act,” says Dave Owen, a UC Law, San Francisco professor who has a background in geology and focuses on water resource management. “Science helps strike that balance.” … ” Read more from Robin Meadows at Maven’s Notebook.
DWR partners with agencies to untangle mystery of California’s harmful algal blooms
“Appearing like something out of science fiction, harmful algal blooms (HABs) can form thick mats that accumulate on freshwater surfaces throughout California. Most common during the summer, HABs are a nuisance that can smother entire portions of waterways, sucking oxygen from the system as they decompose, while producing toxins which can be dangerous to humans and pets. DWR is addressing the issue by drawing on its own expertise and that of partner agencies to better understand the drivers and dynamics of HABs. DWR is in the midst of a five-year, $3 million research project by the National Oceanic and Atmospheric Administration (NOAA) National Centers for Coastal Ocean Science’s Monitoring and Event Response for Harmful Algal Blooms program, or MERHAB, with the aim of developing a HAB monitoring program for the Bay-Delta estuary. … ” Read more from DWR.
In commentary this week …
Recharge the valley: Why California’s water future depends on groundwater
Jim Mayer, chair of the Northern California Water Groundwater Management Task Force, and Michael Saunders, chair of the Regional Water Authority, write, “By any honest measure, California is living in water extremes. Long droughts empty reservoirs, idle farmland, and impact our environment. Then, atmospheric rivers roar through the Sacramento Valley, sending millions of acre-feet of freshwater to the ocean in a matter of days. We lurch between scarcity and surplus—yet act as though we can’t store the water when it is most abundant. That paradox is no longer acceptable. A solution is beneath our feet. Groundwater recharge—intentionally moving high flows onto fields, floodplains, and dedicated basins so they percolate into aquifers, or shifting water supplies to leave more groundwater in storage—is a practical, affordable, and scalable storage system in California. When done through managed programs with clear accounting and sustainability safeguards, it allows regions to capture water during wet times for use during dry times. And now, after a decade of experience under the Sustainable Groundwater Management Act (SGMA), it is clear we need legislation that makes recharge easier, faster, more affordable, and more certain. … ” Continue reading at Maven’s Notebook.
A flood of hope
Ted Sommer writes, “My most inspiring bike ride this past year was not on a mountain or in some exotic destination. It was sixteen flat and muddy valley miles under overcast skies. My destination was a new concrete structure designed to reconnect the Sacramento River with its adjacent floodplain, the Yolo Bypass. This habitat restoration project reflects decades of work by my team and represents one of the most important steps to save Central Valley salmon. In the late 1990s, I worked full-time as a scientist for California Department of Water Resources while moonlighting as a U.C. Davis Ph.D. student. Like several other scientists in my cohort, I was trying to answer the question of why wet years are so good for many species in the Bay-Delta and its watershed. I chose to study the Yolo Bypass, the primary floodplain of the region. … ” Read more at the California Water Blog.
Without federal climate action, California’s wild native fish face almost certain extinction events
“California Trout is deeply concerned by the repeal of the federal endangerment finding, a decision that departs from decades of scientific consensus and raises serious implications for the health of our wild fish, rivers, communities, and climate. At California Trout, we know that the climate crisis is real. Climate change is the primary threat to our organization’s mission of revitalizing waters for resilient wild fish and a better California — and human activity is the principal cause. The endangerment finding has long reflected the best available science showing that climate pollution poses risks to public health and welfare. Rolling it back does not align with the realities Californians are already experiencing: more extreme heat, intensified droughts, floods, and wildfires, shrinking snowpack, and warming waters. “The endangerment finding reflects decades of rigorous scientific research showing that climate change poses clear risks to both human and ecological systems,” said Darren Mierau, Director of Science at California Trout. … ” Read more from Cal Trout.
California’s dry farmland is ideal for solar. Big Ag stands in the way
The McClatchy California Editorial Board writes, “The Trump administration has all but declared war on wind and solar projects, making it more important than ever for states to promote clean energy. That’s why it’s disappointing that California would let an important solar bill languish. Assembly Bill 1156, authored by Buffy Wicks, D-Oakland, passed both the Assembly and Senate last year, but was shelved in September, following objections from the California Farm Bureau and other organizations. The Trump administration has all but declared war on wind and solar projects, making it more important than ever for states to promote clean energy. That’s why it’s disappointing that California would let an important solar bill languish. Assembly Bill 1156, authored by Buffy Wicks, D-Oakland, passed both the Assembly and Senate last year, but was shelved in September, following objections from the California Farm Bureau and other organizations. … ” Continue reading at the San Luis Obispo Tribune.
Permitting reform vs. farm reality: Will faster federal reviews help producers?
Dan Keppen, Executive adviser, Family Farm Alliance, writes, “In Washington, D.C., “permitting reform” has become one of the hottest phrases in policy circles. Lawmakers and regulators are debating major changes to how projects move through the National Environmental Policy Act (NEPA), Clean Water Act permitting, and related environmental reviews. The stated goal is simple: build things faster. Move infrastructure. Cut red tape. Reduce delay. For farmers and ranchers, the question is more practical: Will any of this actually make it easier to get real work done on the ground? … ” Read more from the Western Farm Press.
In regional water news this week …
39,860 natural adult Chinook salmon returned to Klamath River 2 years after dam removal completed!
“A total of 39,860 adult fall-run Chinook salmon returned to spawn in the Klamath River and its tributaries in the fall of 2025, two years after dam removal was completed. That’s according to the just-released Review of 2025 Ocean Salmon Fisheries published by the Pacific Fishery Management Council (PFMC) on February 18: www.pcouncil.org/… The return was 205 percent of the preseason prediction of 19,417 adults, according to the document used to help craft West Coast commercial, Tribal and recreational salmon fishing season alternatives every year in preparation for the PFMC’s meeting in March 2026. “The 2025 preliminary postseason river run size estimate for KRFC was 51,277 adults compared to the preseason-predicted ocean escapement (river run size) of 28,554 adults,” the review stated. “The escapement to natural spawning areas was 39,860 adults, which was 205 percent of the preseason prediction of 19,417 adults.” … ” Read more from Dan Bacher at the Daily Kos.
‘It’s unfortunate’: Officials disappointed fish farm backed out
“With Nordic Aquafarms backing out of a proposed aquaculture facility on the Samoa Peninsula after about seven years of planning and regulatory work, public officials said they are disappointed but feel confident another project will happen at the former pulp mill. “We are aware that Nordic no longer intends to pursue a project on the Samoa Peninsula and are working with Nordic and the county for the orderly wind-down of the project,” said Chris Mikkelsen, executive director of the Humboldt Bay Harbor, Recreation and Conservation District, in a statement sent by email. This development, reported by the Lost Coast Outpost, follows a number of signs of shrinking local presence of the Norway-based company. The Outpost reported the company submitted paperwork to formally dissolve the California-based affiliate last month. … ” Read more from the Eureka Times-Standard.
Busted pipe at Yuba power plant kills salmon, renews infrastructure fears
“River conservationists on Wednesday urged state regulators to reassess how aging hydropower infrastructure is operated and maintained — and, in some cases, whether certain facilities should remain in place — following a 14-foot diameter, high-pressure water pipe ruptured last week. While praising the immediate emergency response of Yuba Water Agency and California Department of Fish and Wildlife, advocates said the rupture raises broader questions about how dams and related infrastructure are managed in California. Friday’s penstock rupture in Yuba County, which hit as Yuba Water Agency was finishing a major tunnel and penstock upgrade at its New Colgate Powerhouse, has left the utility and state wildlife officials scrambling to clean up sediment and debris and to restore flows on the lower Yuba. A penstock is a large, pressurized pipe that carries water from a reservoir into a hydropower plant and then back into the river. … ” Read more from the Sacramento Bee.
Yuba agency redirects funds, rejects extra salmon habitat request
“Following a large water pipe rupture at the Colgate Power Plant which led to hundreds and possibly thousands of salmon killed in lower Yuba River, Yuba Water Agency on Tuesday announced the $300,000 grant to a local conservation group for its fish restoration project, while turning down a second bid for a separate fish habitat effort. The awarded Upper Long Bar Restoration Project was proposed by the South Yuba River Citizens League to create juvenile salmon rearing habitat on the lower Yuba River and approved in January for about $1.8 million in grant funding by the California Department of Fish and Wildlife. Tuesday’s grant is part of that larger restoration package, under which the Yuba Water Agency will contribute up to $300,000 in matching funds. … ” Read more from the Sacramento Bee.
Meet the stormwater robots
“The day before the first major fall storm in 2025, Kayli Paterson took four of her new coworkers to creeks in Richmond, Albany, and Oakland, tied them up securely, and left them. Like others on the sampling team, the new members were braving the storm to collect samples of contaminants in urban stormwater runoff. Unlike the rest of the crew, they weighed 25 pounds each and were the size of bulky briefcases. After three years of scheming, tinkering, and trial and error, Paterson and the SFEI team are putting a fleet of stormwater sampling robots to work. “Our little robot samplers, they don’t need showers. They don’t need sleep,” says Don Yee, who developed the first generation of samplers in 2023 and built the new robots along with Paterson and a small team. “They just need their batteries charged.” … ” Read more from the San Francisco Estuary Institute.
Hundreds of unplugged oil wells sit on top of groundwater sources in Monterey County, a study finds.
“California’s oil industry is over 150 years old, with its commercial beginnings traced back to the fittingly named Petrolia in Humboldt County. Production peaked in the 1980s before entering a steady decline, with wells falling out of production and creating a scattered and increasingly difficult problem to manage throughout the state. Today, there are more than 30,000 idle oil and gas wells, defined as wells that have been inactive for at least 24 months. Although these wells are no longer commercially productive, they can still leak oil and emit pollutants, including carcinogens like benzene and formaldehyde, air emissions including methane and pose physical hazards. In California, at least 4,449 of these wells are within 3,200 feet of a school, hospital, playground or elder care center, according to an analysis conducted by the nonprofit Center for Biological Diversity. The threats posed by idle wells in Monterey County, however, raise different concerns: The risk is less about neighboring hospitals or other actively used sites and more about drinking water reserves. … ” Read more from Monterey County Now.
East Orosi’s $13.5M safe water project nears state approval after years of delays
“After a series of delays, a $13.5 million project to supply safe drinking water to the community of East Orosi is expected to receive state approval later this month. The project is funded by the state’s Drinking Water State Revolving Fund, specifically by an Emergency Drinking Water Assistance Grant. The use of the word “emergency” to describe the funding of the long-delayed project has an irony that is not lost on Denise England, Tulare County grants and resources manager. “We have reminded the state of that on a number of occasions,” she said. “You call this an emergency and we’re ready to go, and you all are still reviewing things and deciding with your attorneys whether or not we can actually go. It’s quite frustrating.” … ” Read more from the Visalia Times-Delta.
Kings County groundwater agency approved $360,000 “ballpark” cost for drying wells
“The Mid-Kings River Groundwater Sustainability Agency (GSA) will spend $360,000 to repair four dry wells in its boundary caused by excessive groundwater pumping. The Mid-Kings board approved drilling three new domestic wells and connecting one home to the City of Hanford’s water system during its Feb. 17 board meeting. This is all part of its $2 million pilot program to help owners repair well damages. “This is a very ballpark budget based on the understanding that we have of the wells, understanding of how much pipe we have to run,” engineering consultant Amer Hussain told the board. … ” Read more from SJV Water.
‘Small water user:’ Some farmers facing a Cuyama Valley groundwater rights lawsuit could get help from new state legislation
“There’s plenty of legal jargon that goes over Jake Furstenfeld’s head when he tunes in via Zoom to court proceedings tied to a Cuyama Valley groundwater dispute. This wasn’t the case, however, when the local rancher and others with stakes in a lawsuit over water rights for a critically overdrafted basin heard a judge’s tentative order in early February. “That was one of the first positive things that had come out of this,” Furstenfeld said. “It kind of gave me a glimmer of hope.” While citing newly passed state legislation, Los Angeles Superior Court Judge William Highberger said that he would potentially exempt around 100 Cuyama Valley growers and residents considered “small pumpers,” due to their low water use, from the adjudication. A follow-up hearing is scheduled for early March. … ” Read more from the Santa Maria Sun.
Nearly half of L.A County’s pavement may be unnecessary, new map finds
“Los Angeles is often described as a concrete jungle, a city shaped by asphalt, parking lots and other hardscape. Now, for the first time, researchers have mapped that concrete in detail, and they claim a lot of it doesn’t need to be there. A new analysis finds that some 44% of Los Angeles County’s 312,000 acres of pavement may not be essential for roads, sidewalks or parking, and could be reconsidered. The report, DepaveLA, is the first parcel-level analysis to map all paved surfaces across L.A. County, and to distinguish streets, sidewalks, private properties, and other areas. The researchers divided all pavement into “core” and “non-core” uses. A street, for example, is core. Then they paired that map with data on heat, flooding and tree canopy, creating what they intend as a new framework for understanding where removing concrete and asphalt could make the biggest difference for people’s health and the climate. … ” Continue reading at the LA Times.
What are nurdles? The tiny plastic pellets threatening San Diego’s lagoons
“Something tiny is hiding in San Diego’s sand, washing into our lagoons, and working its way up the food chain. It arrives by freight train, escapes by the billions, and has been polluting our most protected coastal habitats for decades with almost no oversight. It’s called a nurdle, and we’re doing something about it. Nurdles are tiny pre-production plastic pellets, roughly the size of a lentil or fish egg (1–5 mm). They’re the raw material used to manufacture virtually every plastic product in existence. Water bottles, food packaging, car parts, toys: it all starts as a nurdle. Nurdles are produced in massive quantities — the U.S. alone manufactures approximately 27 million tonnes annually. As plastic is sourced from fossil fuels, the explosion in natural gas fracking in the U.S. has led to a boom in plastic production. Nurdles are then shipped by rail, truck, and cargo ship to factories around the world where they’re melted down and molded into consumer products. And at nearly every step of that journey, they escape. … ” Read more from the San Diego Coastkeeper.
Interior Department moves forward on guidelines for Colorado River absent full state consensus
The Department of the Interior is moving forward with the Post-2026 NEPA process to finalize operating guidelines for Colorado River reservoirs by Oct. 1, 2026. While the seven Basin States have not reached full consensus on an operating framework, the Department cannot delay action. Meeting this deadline is essential to ensure certainty and stability for the Colorado River system beyond 2026. “Negotiation efforts have been productive; we have listened to every state’s perspective and have narrowed the discussion by identifying key elements and issues necessary for an agreement. We believe that a fair compromise with shared responsibility remains within reach,” said Secretary of the Interior Doug Burgum. “I want to thank the governors of the seven Basin States for their constructive engagement and commitment to collaboration. We remain dedicated to working with them and their representatives to identify shared solutions and reduce litigation risk. Additionally, we will continue consultations with Tribal Nations and coordinate with Mexico to ensure we are prepared for Water Year 2027.” … Continue reading from the Department of the Interior.
As a Colorado River deadline passes, reservoirs keep declining
The leaders of seven states announced Friday, one day before a Trump administration deadline, that there is still no deal to share the diminishing waters of the Colorado River. That leaves the Southwest in a quagmire with uncertain repercussions while the river’s depleted reservoirs continue to decline. Former U.S. Interior Secretary Bruce Babbitt said in an interview with The Times that the impasse now appears so intractable that Trump administration officials should take a step back, abandon the current effort and begin all over again. Babbitt said he believes it would be a mistake for Interior Secretary Doug Burgum to “try to impose a long-term solution” by ordering major water cuts across the Southwest — which would likely set off a lengthy court battle. “We need a fresh start,” Babbitt said. “I believe that in the absence of a unanimous agreement, [the Interior Department] should renew the existing agreements for five years, and then we should start all over. We should scrap the entire process and invent a new one.” … Read more from the LA Times. | Read via Yahoo News.
With no Colorado River deal in sight, risk of federal action intensifies. Here’s what that means.
“J B Hamby spent an evening in Southern California last week flipping through pages full of Colorado River meeting notes reflecting the same arguments and negotiating positions over the waterway’s future dating back to 2023. “I’ve kept all my notebooks since I began this sick, twisted hobby back in early 2023,” Hamby, the state’s top negotiator on Colorado River issues, said Friday. “Our real issue is not that we’ve run out of time. … The problem is that we don’t have sufficient compromise all around to be able to close a deal.” He’s not the only state negotiator feeling the frustration: There was no love between opposing blocs in the basin as they failed to meet a Valentine’s Day deadline. The seven Colorado River states, including Colorado, are trying to reach a joint agreement on how to manage the river basin’s water supplies before the current rules expire this fall. Without state consensus, President Donald Trump’s administration will decide what to do. With every missed deadline, the risk of expensive, yearslong court battles over water heightens, and communities are left in limbo. Coloradans are nervous the president could contradict a century of water law and give water to states he favors. … ” Read more from the Colorado Sun.
