California WaterBlog

by Peter B. Moyle Tired of reading about the constant haggling over California water? Or of binge-watching old TV shows? Or, worse, watching the news as the Covid 19 virus spreads in our free country? For relief, I recommend two entertaining yet somewhat off-beat books, reviewed here. The books are very different but both involve…

by Kathleen Schaefer and Brett F. Sanders Why Dialogue Matters For fifty years, Flood Insurance Rate Maps (FIRMs) have unintentionally stifled conversations of flood risk. They have encouraged property-owners and governments at all levels to dwell on map details for one static event, rather than flood risks for a range of events under changing conditions…

by Jay Lund Agriculture is California’s predominant use of managed water.  Agriculture and water together are a foundation for California’s rural economy.  Although most agriculture is economically-motivated and commercially-organized, the sociology and anthropology of agriculture and agricultural labor are basic for the well-being of millions of people, and the success and failure of rural, agricultural,…

By Nicole Osorio Most people in California receive some of their drinking water supply from the State Water Project (SWP). The SWP also supplies water to over 10% of California’s irrigated agriculture.  The SWP and its service area span much of California, delivering water to 29 wholesale contractors shown in Figure 1. Each year, the…

by Ryan Peek Foothill Yellow-legged Frogs have begun to spawn, laying small snow-globe sized egg masses in streams and rivers. They are one of the few stream-breeding frogs endemic to California and Oregon. This species is a good indicator of stream health because they link aquatic and terrestrial ecosystems and are strongly tied to natural…

by Alvar Escriva-Bou, Jay Lund, Josue Medellin-Azuara, and Thomas Harter Earlier this year, the first local Groundwater Sustainability Plans (GSPs) were submitted to California’s Department of Water Resources for basins with the most severe groundwater overdraft.  To comply with the Sustainable Groundwater Management Act, these plans must address any “significant and unreasonable” impacts of groundwater…

by Peter Moyle, Jeanette Howard, Ted Grantham “Nowhere is the biodiversity crisis more acute than in freshwater ecosystems” (Tickner et al. 2020) Weeks of being confined indoors under shelter-in-place orders increases our appreciation of the natural world. Walking and exercising outdoors, especially along a local stream like Putah Creek, is one of the best ways…

By Thomas Harter, Steph Tai, and Karrigan Bork In 1972, the U.S. Clean Water Act (CWA) created a permit system for point source discharges to navigable waters of the United States – rivers, lakes, and coastal waters – with the goal of restoring and protecting their water quality. Typically, these permits are issued by the…

by Dylan K. Stompe Striped bass are an iconic and recreationally important fish species throughout the United States, including within their native range on the Atlantic Coast. Based on their value as a sport fish and as table fare, striped bass were one of the early introductions to the San Francisco Estuary (SFE). Their life-history…

by Peter Moyle, Center for Watershed Sciences, UC Davis Delta smelt are an endangered species and the latest estimates of their numbers indicate they will likely not be around much longer as wild fish. When I first started working on them, in the 1970s, they were abundant and frequently caught in various sampling programs. One…

by Nestle J. Frobish Today the Megalopolitan Water District of California (a consortium of southern California and Bay Area urban water suppliers) proposed building a new aqueduct to take water from the Sacramento River to Bay Area and southern California cities.  The aqueduct, depicted below, would avoid the subsurface uncertainties of a Delta tunnel, ease…

by Jay Lund Not again! There was not a “Miracle March” to follow California’s precipitation “Flat-line February.”  Instead, we’ve had a “Meh March.” With the near-end of its wet season, California’s 2020 water year is and will be dry.  The Northern Sierra 8-gage Precipitation Index is now about 25 inches, and might increase about 10%…

By Alyssa Obester, Sarah Yarnell, and Ted Grantham The California Environmental Flow Framework was recently highlighted in the 2020 Water Resilience Portfolio to address the seemingly impossible task of establishing of how much water our rivers and streams need to support healthy ecosystems. While many methods for setting environmental water needs exist, the Framework provides…

by Peter Moyle, Dylan Stompe, and John Durand The Sacramento splittail is a lovely, silvery-white fish that lives primarily in Suisun Marsh, the north Delta and other parts of the San Francisco Estuary (SFE; Moyle et al. 2004). The name comes from its unusual tail, in which the upper lobe is larger than the lower…

    By Jay Lund February has been amazingly dry in California, if anyone hasn’t noticed.  No precipitation at all in February, a dry forecast, about 51% of seasonal Sacramento Valley precipitation (a bit less for the San Joaquin and Tulare basins), and only about half (45-57%) of normal snowpack for this time of year. …

By Bill Fleenor, Amber Manfree, and Megan Nguyen This is a re-posting from January 22, 2017.  Reminders on how things work are sometimes useful. (The whole series, with links below, is thought-provoking.) In 2010, John DeGeorge of RMA, Inc used animated model results to illustrate specific flow and water quality issues in the Delta to…