Science and report notes: State Water Board and NorCal coastal streams, forecasting salmon returns, streamgages, EPA's National Aquatic Resources Survey, and more
State Water Board proposing draft policy on Northern California coastal streams, public comment period ends April 8: The policy adopted in 2010 was vacated due to litigation, so a revisions were necessary: “The Policy will apply to applications to appropriate water, registrations, andwater right petitions. The Policy will establish principles and guidelines for maintaining instream flows for the protection of fishery resources. It will prescribe protective measures regarding the season of diversion, minimum bypass flows, and maximum cumulative diversion. The Policy contains guidelines for evaluating whether a proposed water diversion, in combination with existing diversions in a watershed, may affect instream flows needed for the protection of fishery resources.” More information here: Notice of filing, State Water Board’s program page
Forecasting salmon returns: The FishBIO blog discusses the methods the Pacific Fisheries Management Council (PFMC) uses to estimate returning salmon, which at times have been far greater than the actual number. How can this be improved? ” … Currently, estimates are made using a regression that relates the previous year’s jack (early maturing males) escapement to the following year’s total escapement. Essentially, the method predicts that if there are a lot of jacks in the basin this year, then next year will be a good year for salmon. In 2011, the total Chinook salmon jack escapement was greater than any year on record (85,719), and the current regression would have estimated a total of more than two million Chinook salmon returning in 2012! In an effort to come up with a more realistic forecast, PFMC used the data from only recent years (2009-2011) to come up with a modified regression that decreased the 2012 SI forecast to 819,400 Chinook salmon. The modified forecast still overestimated by 25%, but was more accurate than predictions in 16 of the last 20 years. … ” Read more here from the FishBIO blog: Salmon forecast: a chance to reflect and improve
The importance of streamgages: The USGS Water Science Center highlights the importance of streamgages: “Reliable streamflow information is needed for many purposes: for flood warnings and forecasts; drinking water management; irrigation withdrawals; hydroelectric power production; wastewater discharges and reservoir releases; legal and treaty obligations on interstate and international waters; preservation of aquatic habitats; water quality standards; recreation; infrastructure designs for highways, bridges, culverts, dams, and levees; and for scientific investigations of streamflow history, ecosystem health, and climate change.” All the more important when you consider that the USGS will be discontinuing operation of up to 375 streamgages nationwide due to budget cuts as a result of sequestration. Read the article from the USGS California Water Science Center here: Measuring the Flow: The Importance of Streamgages
What if Australia’s water conservation practices were adopted here? Australia provides a good benchmark for California as it has a similar climate, economy and culture. A new journal article by UC Davis’ Ryan Cahill and Jay Lund determined: “If California had the same residential water use rates as Australia, it could have reduced gross urban water use by 2,600 GL (2.1 million acre-feet) in 2009 and potentially saved 1,800 GL (1.5 million acre-feet) for consumptive use by others.” More here: Residential Water Conservation in Australia and California
EPA assessment finds more than half the nation’s waterways are are in poor condition: The EPA’s National Aquatic Resources Survey, released yesterday, has found 55% of the rivers, lakes, bays and coastal waters are in poor condition for aquatic life. Findings include excessive nitrogen and phosphorous levels, increases in bacteria and mercury, and decreased vegetation cover due to human disturbance. More here: EPA’s National Aquatic Resource Survey
Water Withdrawal Regulations by State: The National Conference of State Legislatures has a handy guide to water withdrawal regulations by state. Check it out here: State Water Withdrawal Regulations
Aguanomics David Zetland sets up water data hub: Frustrated by his inability to find a centralized source of water data, Zetland sets up his own. The Water Data Hub (WDH) is “a central location that links to water data, no matter where it is, who owns it, or what dimension of water it describes. Last November, I asked for help on this project, and Ian Wren (from San Francisco) joined me. It’s thanks to Ian’s hard work (weekends and evenings!) that I can now invite you to visit waterdatahub.org! So, please go there and add data sources. The WDH, like any network, gains value with the number of links.” This is a regurgiated post from a year ago, so the site by now has been populated somewhat. More information from Aguanomics here: The water data hub is LIVE!
Floodplains and salmon: UC Davis scientists test flooded postharvest rice fields as habitat for salmon in this YouTube video:
Photo from the Aquarium of the Pacific by Chris Austin (Maven).