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Before plunging into more ways to save water, let’s reassess current conditions in California. We reported as recently as December that all the major California reservoirs were at historic highs. This is still true, with most of these reservoirs still recording more than 100% of their historical averages.
More important at this time of year, however, is the status of the California snowpack. The development of snow hydrology and its connection to water supply forecasting dates back to the early twentieth century and Dr. James E. Church, Jr., who taught–of all things–Latin, German and fine arts at the University of Nevada in Reno, and invented the snow measurement device that, according to the American Meteorological Society, is still almost exclusively in use today in the western United States.
Snowpack levels this winter, as compared to the reservoirs, are not so encouraging. The CA Department of Water Resources’ (DWR) Second 2012 Snow Survey, released on February 1, confirms that “water content in California’s mountain snowpack is far below normal for this time of year.”
Quoting further: “Statewide, the snowpack water content is 37 percent of normal for today’s date and 23 percent of the normal April 1 seasonal total.” “DWR’s initial estimate is that the State Water Project (SWP) will be able to deliver 60 percent of the slightly more than 4 million acre-feet of water requested this calendar year by the 29 public agencies that supply more than 25 million Californians and nearly a million acres of irrigated farmland. The 60 percent delivery estimate is largely based on the known quantity of carryover reservoir storage.”
An acre-foot, by the way, is approximately 326,000 gallons, so we’re talking about over a trillion gallons, a quantity of water not really imaginable by the average citizen. And to say that DWR is hedging its bets would be putting it mildly, given that DWR projections, as quoted above, are based on what’s already in the reservoirs.
DWR’s data, dizzyingly replete with tables, graphs, and comparative figures, can be found at cdec.water.ca.gov. For example, you can access the entire monthly history of reservoir storage for Lake Powell dating back to 1963, just before the Glen Canyon Dam went into service. Another table shows that Lake Powell and Lake Mead together are currently at 83% of their historical average.
In simple terms, the snowpack peaks about the first of April (as referenced by DWR above), and runoff from snowmelt peaks about the middle of June.
The winter months typically require less water use, but the coming hot months of summer are waiting ahead. We humans can measure the data, but nature makes the ground rules. What will nature provide in the coming months? Will it remind us once again how precious water is?
Published: February 23, 2012 – Volume 10 – Issue 45