Officials: Strong start to water year drying up
January 31, 2013
An extremely wet beginning to the California water year has acted only as a false harbinger, weather officials say.
“It’s looking more and more like we are going to experience a dry year,” said Drew Peterson, National Weather Service meteorologist.
After the second snowpack survey of 2013 was measured Tuesday, officials with the California Department of Water Resources reported water content in California’s mountain snowpack is below average for the date. This comes only a month after officials were reporting snowpack conditions to be well above average.
“We are off to a good water supply start for the new year, but we have to remember that we have seen wet conditions suddenly turn dry more than once,” DWR spokesman Ted Thomas said in December.
Thomas’s caution has proved wise as DWR’s readings demonstrated statewide water content at 93 percent of average for this time of year. The water content is at 55 percent of the average April 1 measurement, when the snowpack is normally at its peak before the spring melt.
“We’re still seeing decent snowpack conditions due to storms in late November and early December,” said DWR Director Mark Cowin. “Those early season storms also erased the deficit in our reservoir storage, but relatively dry weather this month is once again a reminder that the weather is unpredictable and we must always practice conservation.”
In December, a huge storm, commonly referred to as an atmospheric river, dumped copious amounts of precipitation in all the northern regions, Peterson said.
But precipitation has been relatively absent since, and “things are looking more and more like a struggle to reach an above normal, or even a normal year,” he said.
Typically, January is the wettest month for the region, stoking fears that the water year will not be as productive as originally heralded by some weather officials, Peterson said. February and March also typically see large numbers of storms, according to historical trends, but by the time April arrives, rainfall is often in short supply.
Peterson said the earliest Sierra foothills residents can expect water is Sunday, but long-range climate models still predict a sustained period of dry weather.
Electronic readings indicate that the water content in the northern mountains is 97 percent of normal for the date and 59 percent of the April 1 seasonal average, according to a DWR news release. Electronic readings for the central Sierra show 90 percent of normal for the date and 54 percent of the April 1 average. The numbers for the southern Sierra are 91 percent of average for the date and 51 percent of the April 1 average.
DWR currently estimates that it will be able to deliver 40 percent of the slightly more than 4 million acre-feet of State Water Project water requested for this calendar year by the 29 public agencies that supply more than 25 million Californians and nearly a million acres of irrigated farmland. The delivery estimate may increase as more winter storms develop.
The final allocation of State Water Project water in calendar year 2012 was 65 percent of requested deliveries. The allocation was 80 percent in 2011, 50 percent in 2010, 40 percent in 2009, 35 percent in 2008, and 60 percent in 2007.
The last 100 percent allocation — difficult to achieve even in wet years because of restrictions on Delta export pumping to protect sensitive fish species — was in 2006.
To contact Staff Writer Matthew Renda email mrenda@theunion or call 530-477-4239.