BEFORE AND AFTER THE RAIN: Two views of Mansfield Dam Park on Lake Travis show the impact of heavy rains in recent weeks. The top photo: A parched landscape on Jan. 11, about the time Lake Travis was 37 feet below its normal full elevation. Bottom: The scene is dramatically different in this early June photo, as a replenished Lake Travis has risen to "full" elevation.

June 8, 2007

AUSTIN – In mid-December 2006, LCRA Meteorologist Bob Rose stood where Lake Travis used to be.

Rose was at Bob Wentz Park at Windy Point, looking out to the lake that had receded to a 42-year low for December. Lake Travis was more than 37 feet below full elevation, thanks to a two-year drought that continued to grip the Hill Country, even as it had begun to retreat from the rest of the lower Colorado River basin.

At Windy Point, Rose noticed three pumpkin-sized orange buoy markers, which were supposed to mark the swim area, nestled on the sandy lakebed. Nearby, a boat ramp lay useless, marooned several feet away from the lake. (See video.)

“The question people kept asking me was, ‘When is it going to rain?’” Rose recalled. “Lots of people were asking that question.”

With good reason. The lack of rain was not just inconveniencing swimmers and boaters at Windy Point but affecting all residents throughout the basin who depended on Lake Travis and its sister reservoir, Lake Buchanan, for water.

At mid-December the drought had left the two water-supply reservoirs little more than half full, forcing LCRA to implement conservation measures among its water users, including a first-time-ever curtailment of “interruptible” water supplies for agricultural users.

Faced with a distinct possibility that the dry weather pattern could continue, LCRA hydrologists contemplated that drought conditions in the region could soon surpass those of the decade-long Drought of Record of the 1940s and ’50s.

Six months later: the drought is gone
What a difference six months makes. Fast forward to early June. If Rose were standing at the swim area at Windy Point, the buoys would be bobbing in water at least 10 feet over his head. The boat ramp also is back in the water and back in service.

LCRA’s two water-supply reservoirs, Lake Travis as well as Lake Buchanan upstream, are virtually full, thanks to the return of rains earlier this year that, through late May, had generated 877,410 acre-feet (nearly 286 billion gallons), roughly 44 percent of what the two lakes can hold.

Lake Travis is about 39 feet higher, with LCRA having spent more than a week releasing water from Travis’ flood pool to bring the lake back to full elevation. Lake Buchanan is also up by more than 18 feet, a little less than 2 feet below its full elevation for this time of year.

The fuller lakes have allowed LCRA to ease back from its preparations for a drier, dire summer. While LCRA continues to encourage customers to conserve, it has eased the curtailment on interruptible water sales.

And the drought? The drought, which was on most people’s minds for more than two years, is now mentioned in the past tense, if at all. It’s over. It’s been deep-sixed.

Rains fell, but not as forecasters had anticipated
As usual, rain – lots of it – vanquished the drought and refilled the lakes. What is unusual is that the rains occurred in a pattern that the weather forecasters didn’t expect.

An “El Niño” weather pattern, which typically results in above-average rains for the basin, had come and gone earlier this year without offering much relief to the Hill Country, which continued to experience severe to extreme drought conditions, according the U.S. Drought Monitor, even as drought conditions downstream were easing. Lakes Travis and Buchanan were a little more than half full.

“The Hill Country received some rains in late December and mid-January, but almost as a glancing blow from storms that were focused along the Interstate 35 corridor and areas downstream,” Rose said.

Lake Travis, which had started 2007 at 644.1 feet above mean sea level (msl) – almost 37 feet below full elevation – gained more than 3 feet from the January rains, then started to decline in February as the dry weather returned.

“El Niño had left the region by February, and we were quickly moving toward a drier ‘La Niña’ weather pattern,” Rose said. “It looked like we were in for a third year of drought.”

And then in March the rains returned – three waves of storms that finally targeted the Hill Country as well as downstream, generating 284,860 acre-feet (almost 93 billion gallons) of runoff into the Highland Lakes – and boosting Lake Travis by more than 19 feet. The wet pattern continued through April and early May, boosting Travis another 4 feet.

Then came the storms of May 24-28. Rains of 8 inches or more fell throughout parts of the lower Colorado River basin, with some locations receiving as much as 12 inches. The storms generated 270,440 acre-feet (more than 88 billion gallons) of runoff into the Highland Lakes, about 95 percent of what the lakes collected from the three March storms.

The storms topped out Lake Travis, which rose more than 9 feet from May 25 to 682.5 feet msl as of June 5, about a foot and a half above full elevation into the lake’s flood pool.

The Lake Buchanan watershed saw little of the January through April rains, rising from a Jan. 1 low of 998.0 feet msl to 1,001.4 April 1 and 1,003.2 May 1. But the May rains targeted more of the Buchanan watershed, causing the lake to rise by almost 13 feet to 1,016.1 June 5. At 1,018 the lake is full for this time of year.

Lake Travis, Mansfield Dam also protected people, property and the environment
Besides helping capture storm runoff for use as the basin’s future water supply, Lake Travis performed another purpose for which it was created – protecting Austin and other downstream communities from the worst effects of the Hill Country storms.

If Lake Travis and Mansfield Dam, which forms the lake, didn’t exist, most of the more than 88 billion gallons of runoff from the late May storms would have flowed through Austin and downstream, largely unchecked, according to LCRA River Operations Manager Mark Jordan.

As it happened, LCRA controlled releases from Lake Travis through Mansfield Dam’s hydroelectric power station so that the releases from Mansfield Dam were no more than 5,000 cubic feet per second, which helped keep Lake Austin and Town Lake well within their normal elevation ranges. The controlled releases also kept the Colorado River downstream below flood stage.

Drought could recur – but flooding a more immediate concern
While LCRA officials are happy about the end of the drought, they are also cautious about what may happen next. In a region where the weather is characterized as a continuous drought interrupted by the occasional flood, the officials caution that drought conditions, though vanquished, could likely recur within a year or two.

“In 1952, during the Drought of Record, a major flood and subsequent rains refilled Lake Travis nearly 70 feet from its all-time low elevation,” Jordan said. “Yet within another couple of years we were back in severe drought conditions.”

Rose noted that heavy rains and floods in June 1997 topped out the lakes, but by 1999 the basin was locked in a drought that lasted through late 2000.

Even with a drier La Niña settling in later this year, Rose said it’s too early at this point to tell when the basin may be headed back into drought.

“June is typically one of our rainier months,” Rose said. “And this year’s tropical storm season, which began June 1, may be very active.”

The more immediate concern may be the likelihood of flooding, especially if an active tropical season results in heavy rains that generate additional runoff into the already full lakes Travis and Buchanan.

ARCHIVED GRAPHIC: LAKE TRAVIS' RISE

The graphic is a seven-day snapshot of the elevation of Lake Travis at Mansfield Dam following recent rains. Note: This graphic doesn't depict the current elevation of the lake. For current lake level elevation, go to the situation report and scroll down to Lake Travis.

John Williams is a senior writer for the Lower Colorado River Authority.

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