One day in early October, a group of University of California, Merced, students went to the campus Smart Farm, augurs in hand, to explore the soil for the best spots to locate moisture sensors. They were not looking in the root zone to monitor how much water is available but instead for areas lower in the soil to study how irrigation and stormwater can travel far enough beneath the plants to recharge the groundwater below.
The struggle over management of water supplied through the Sacramento-San Joaquin Delta continues as the Biden administration seeks a reversal of rules put in place by agencies under the Trump administration.
Last week, the U.S. Bureau of Reclamation sent a letter to federal fisheries agencies and announced it is reinitiating consultation of the U.S. Fish and Wildlife Service and National Marine Fisheries Service 2019 biological opinions related to the coordinated, long-term operation of the Central Valley Project and State Water Project.
The two water projects are California’s primary water-delivery systems that guide pumping of water through the Sacramento-San Joaquin Delta, sending water south to tens of millions of people and to millions of acres of farmland.
Yale researchers are charting the course of mighty “rivers” in the sky that are holding steady in the face of climate change — for now.
In future decades, however, climate-induced changes to these atmospheric rivers could drastically increase extreme precipitation events in some parts of the world, they report in a new study published in the journal Nature Climate Change.
Atmospheric rivers — long, winding filaments of intense water vapor — account for as much as 90% of the moisture sent toward the North and South poles.
The White House announced Tuesday that it would work to revise building standards for flood-prone communities across the country in the face of climate change, while launching tools to make climate information more accessible to the public.
Lake Tahoe’s water level dropped to a four-year low on Tuesday as gusty winds and the impacts of California’s devastating drought hit the popular tourist destination.
After days of high winds increased evaporation rates, water levels fell to the basin’s natural rim for the first time since 2017, the end of the state’s last drought. The lake normally sits above the rim, which allows for water to flow into the Truckee River. Levels will probably continue to drop, receding below the rim this week, sooner than expected.
The Center for Western Weather and Water Extremes, or CW3E, at Scripps Institution of Oceanography, released its report October 11 on atmospheric rivers during Water Year 2021.
The report, “Distribution of Landfalling Atmospheric Rivers over the U.S. West Coast During Water Year 2021: End of Water Year Summary” shows that more atmospheric rivers landed on the U.S. West Coast in Water Year 2021 than in Water Year 2020. But the majority of those storms reached the Pacific Northwest, not California, where drought conditions have impacted water supply.
“The report on atmospheric rivers shows the variability in weather across the state from year to year,” said Jeff Stephenson, Water Resources Manager with the San Diego County Water Authority. “Through our partnership with CW3E and the AR forecasting tools they’ve developed, it better prepares us in management of our water resources using regional storage. This storage, in conjunction with developing multiple water supply sources in the San Diego region, has prepared us for years when rainfall levels are below normal in the region.”
Water Year 2021 experienced a total of 69 landfalling ARs over the U.S. West Coast, 4 more than Water Year 2020.
• While WY 2021 experienced more ARs, a much larger majority of the ARs only impacted the Pacific Northwest.
• California only experienced AR conditions (IVT >250 kg m–1 s–1) from 36 separate ARs during WY 2021, compared to 43
during WY 2020.
Distribution of Landfalling Atmospheric Rivers over the U.S. West Coast During Water Year 2021: End of Water Year Summary. Graphic: Center for Western Weather and Water Extremes
The lack of AR activity over California for two consecutive water years has resulted in a substantial lack of precipitation.
• A large portion of California received <30% of the normal precipitation for both Water Year 2020 and 2021.
• Coastal Washington and Oregon was the only location in the Western U.S. to receive near or above normal precipitation
during both water years, which is also the region that received a majority of the AR activity.
The San Diego County Water Authority partnered with the Scripps Institution of Oceanography, Center for Western Weather and Water Extremes, at UC San Diego in 2020 to better predict atmospheric rivers and improve water management before, during, and after those seasonal storms. The Center and its partners share best practices in forecast-informed reservoir operations, increased research around atmospheric rivers and droughts, and develop strategies for mitigating flood risk and increasing water supply reliability.
For additional details and graphics go to: https://bit.ly/3mKhkcR
The U.S. Environmental Protection Agency has recognized the San Diego County Water Authority with a 2021 WaterSense Excellence Award for advancing water efficiency through its Qualified Water Efficient Landscaper, or QWEL, program. The Water Authority received one of 34 WaterSense awards last week at the national WaterSmart Innovations Conference in Las Vegas.
Programs from the drought-busting handbook practiced by Southern California water agencies include recycling water, building storm-water capture basins and offering cash rebates for replacing thirsty lawns with xeriscape landscaping.
With the grip from a second year of drought tightening, a regional water-planning agency in the Inland Empire is moving ahead for the first time in its history with a more controversial program: cloud seeding.
Water use in Manteca increased 3 percent overall or 13.6 million gallons last month compared to the depth of the last drought in September of 2017. That’s good news given the city has added more than 8,000 residents since Jan. 1, 2017 for a 10 percent population gain. The bad news it might not be enough. Despite a light dusting of snow Thursday along the high Sierra crest at the upper reaches of the Stanislaus River watershed critical to urban and agricultural users in South San Joaquin County, hydrologists are indicating a number of weather models don’t look promising.
How much is access to water worth? In this episode, we aim to answer that question by looking at the Kern Water Bank, one of California’s largest underground water storage facilities. From above, it looks a lot like a giant puddle. But underneath it has the capacity to hold the equivalent of roughly 500 of New York City’s Central Park Reservoirs. And, as one expert says, it’s the “absolute jewel” of California water banking.
