Slow Start to Snow Season Offers Early Warning Regarding Water Supplies for L.A.
Mid-December 2013 Precipitation Levels Barely Above Driest Year on Record
|LOS ANGELES – The Los Angeles Department of Water and Power (LADWP) today asks water customers to redouble their efforts to reduce water use following the recent LADWP precipitation conditions report that shows nearly-record low snow levels in the Eastern Sierra for this time of year. While it is still very early in the snow season, to date the Mammoth Pass snowpack water content stands at less than 30 percent of normal, with just three inches of water on the ground in the form of snow, whereas in a normal year there would be about 10 inches of water for this time of year. To forecast the amount of runoff that will flow into the Los Angeles Aqueduct, the LADWP gathers Eastern Sierra conditions data from six remote snow sensors that measure the water content of the snow, and from other sources.
“Los Angeles has really pulled together to make conservation a priority, and we need to keep this momentum going given what may look to be the third dry year in a row,” said Jim McDaniel, Senior Assistant General Manager of the water system. “Over the last several years LADWP customers led the nation’s large cities in water conservation, in part by limiting outdoor watering. If you haven’t dialed back your watering yet, now is the time to do it.”
Under the City’s Water Conservation Ordinance, outdoor watering currently is limited to three days a week, which in most instances for residential customers, can be cut back by at least a day during the cooler fall-winter season. Customers are urged to re-set sprinkler times, double-check for leaks indoors and outdoors, and consider replacing their water-thirsty lawn during this dormant growing season. Customers can take advantage of the Cash for Your Lawn Program, which rebates $2 for every square foot of turf removed in favor of California-friendly plants or permeable hardscape.
The LADWP relies upon runoff from the Eastern Sierra as a major source of water for Los Angeles’ four million residents, brought south via the Los Angeles Aqueduct and blended with local groundwater and other imported sources. The LADWP begins gathering remote snowpack water content data in late October. To verify the remote sensor readings, each year on February 1, March 1 and April 1 LADWP snow surveyors journey into the backcountry via snowcats and on snowshoes and skis to measure each location by hand.
When snow first falls, 10 inches of powder is roughly equivalent to one inch of water content. However, as the snowpack settles over time, approximately three or four inches of snowpack equates to one inch of water content. Snowpack records at many of the locations go back almost a century, and the LADWP uses the average of the last 50 years to predict water runoff and deliveries to the City.