Posted: Wed, 22 Feb 2012 07:13 AM - 17,013 Readers

By: Farzad Mashhood

The very welcome winter rains in drought-stricken Central Texas have led to the largest increase in lake levels — three feet at Lake Travis in five days — since Tropical Storm Hermine brought about a foot of rain to the lake in September 2010.

Water levels have been rising gently over a wet winter that has surprised meteorologists by bringing Central Texas more precipitation in the past two months than was recorded in the driest 12 months of the drought.

But the weekend’s rains, topping 3 inches in parts of the Hill Country where the Lower Colorado River Authority’s water-supply reservoirs are located, poured on a ground that has been primed for significant runoff into waterways, said Bob Rose, the LCRA’s chief meteorologist.

Prior rain storms this winter have often petered out before hitting the Hill Country and much of water has been getting soaked into a parched ground that saw rainfall totals of more than a foot below normal in 2011, meteorologists have said. The weekend’s rains were the right kind of slow, soaking rains hitting a wide area in the Hill Country to create a significant rise, said Ryan Rowney, the LCRA’s manager of water operations.

“We’re not out of this drought by any means, but that will certainly give us a new direction,” Rowney said.

Tuesday afternoon, lakes Travis and Buchanan were holding 825,000 acre-feet of water, 41 percent of their total capacity, after holding 767,000 acre-feet Thursday morning. The 7.5 percent rise that equated to about a 3-foot rise in Lake Travis and about a 2.4-foot rise in Lake Buchanan still leaves the lakes at less than half their normal February storage of 1.66 million acre-feet.

(An acre-foot is 325,821 gallons or roughly enough water for three normal households in a year.)

Central Texas needs about 15 to 18 inches of rain in the next three months and at least two feet of rain in the next six months to be out of drought, Rose said. The National Weather Service has said the region will ease out of the La Nina weather pattern by the end of spring, which could bring normal rainfall in June and July, Rose said.

Rowney also said that he expects the lakes to continue to rise to about 832,000 acre-feet by the end of this week.