Posted: Fri, 20 Apr 2012 09:21 PM - 14,304 Readers
By: Farzad Mashhood
Even a return to extreme drought conditions over the next six months wouldn't send Highland Lake levels dropping below the low point that was reached during the worst part of the drought, thanks in large part to a decision to severely limit how much water rice farmers get this year.
Lake Travis dipped all the way down to 626 feet above mean sea level, but a wet winter and spring have pushed the lake level back up to 640 feet. But the Lower Colorado River Authority is predicting that the lake won't dip below 630 feet in the next six months, even if extreme drought conditions return.
Under average conditions, the lake is forecast to rise to about 650 feet, still shy of its maximum level of 681 feet.
In 2011, a year the state's climatologist called the worst single year of drought in history, the sun took more water from the Highland Lakes than the 1 million-plus people who depend on the lakes for their water.
But even combined, evaporation and municipal water customers did not use as much water from the lakes last year as was sent downstream for agricultural purposes, mainly rice farming.
In the 2011 drought, farmers used 433,251 acre-feet from the lakes, municipalities used 184,889 acre-feet and evaporation accounted for 192,404 acre-feet of water lost from the lakes, according to the LCRA's 2011 water use summary released last week. (An acre-foot of water is 325,851 gallons, enough to cover an acre to a depth of 1 foot.)
With the state-approved decision to reduce water releases for farmers to only 25,000 acre-feet, water that might have been sent downstream will remain in storage, protecting lake levels even if extreme drought returns to Texas.
But climatologists don't consider that likely.
"La Niña is dead and buried," John Nielsen-Gammon, the state climatologist, said. "The general consensus among computer models is that we're likely to transition into an El Niño next fall, which would tend to put things on the wet side."
So, is the drought over?
"Which drought?" Nielsen-Gammon said. "The East Texas drought is officially over, and the West Texas drought is still going."
And in between?
"That's where it gets complicated," he said.
Rainfall across Central Texas has been above normal. Through Thursday, Camp Mabry's 13.41 inches of rain this year is 5.21 inches more than normal, according to the National Weather Service. Also, the crops of farmers and ranchers in the region are generally doing well, Nielsen-Gammon said.
According to Thursday's national drought report, 10 percent of Texas remains in exceptional drought, the worst form, with 64 percent of the state in some form of drought. That's down significantly from September's peak, when 88 percent of the state was in exceptional drought and 100 percent was in some form of drought.
The majority of Travis and Hays counties and much of the rest of Central Texas are out of drought, but the Highland Lakes are still less than half full, and the Edwards Aquifer's level continues to drop. The decline prompted San Marcos to bring back Stage 1 watering restrictions Monday.
Models show about equal chances for the next couple of months to be wet or dry, Neilsen-Gammon said. Whether or not the lakes rise and Central Texas fully emerges from the drought depends on that unpredictable climate in the coming months, he said.
Whether the drought draws to a close with continued wet weather or returns with summer temperatures remains unpredictable, but LCRA officials say they are planning for a worst-case scenario.
"We can't control Texas weather, we can't control the inflows (to the lakes), but we can control the demands and our savings account," Walker said.