(CNN) -- The Texas town of Groesbeck is on the verge of running dry.
"We have about two weeks of water left," Groesbeck Mayor Jackie Levingston said. Her central Texas town, population 4,300, is one of the latest victim's of the state's ongoing drought.
A lack of rain and the summer's intense heat -- more than 90 days of triple-digit temperatures -- combined to dry out the Groesbeck water supply.
"We lost more water to evaporation than we were using this summer," Levingston said in a telephone interview.
Fort Parker Lake is the city's primary source of water. Heat evaporation took roughly 731 million gallons of water from the lake. The city used only 54 million.
Groesbeck residents spent Monday waiting on the Texas Department of Parks and Wildlife to approve an emergency three-mile pipeline to divert water off the Navasota River, using a public creek as a stop-gap to shorten the distance.
"Our water comes from a river, that goes into a lake, then comes down a river. We came up with a plan to go around the lake," said the mayor. The city already has approval from another agency, the Texas Quality Commission on Environmental Quality, for seven miles of alternative pipeline, but with the clock ticking, Levington said residents can't afford the two weeks to lay the piping in the approved plan.
The new plan will take the city four days to construct.
"I might as well be optimistic," the mayor said, laughing.
There is a bit to be optimistic this week -- Thanksgiving week.
Outside of the local federal prison, the school district is the biggest water user. Some 1,600 children -- many from outside the city limits in surrounding Limestone County -- draw on Groesbeck's water supply on school days. But schools are out for the holiday this week.
"We are counting on this to extend our usage," said Levingston. She speculates it may buy the town an extra week.
The pipeline, when it happens, is a temporary fix. It will cost $200,000 in construction, and $35,000 per month on pipe rental.
The city is calculating using it for six months even though officials have drought-forecast beyond that.
The city also is contracting with a well driller out of Austin to search for ground water.