The cities of Leander and Granite Shoals asked the state to lift the ban in part because it's cheaper to dump the waste in the lakes rather than use it for irrigation or other land-based applications. Proponents of the plan say the plants will help foster economic growth, that "reclaimed" water from sewage treatment plants is safe and that it will help refill lakes that have been stressed by a blistering drought.
Granite Shoals, located on the shores of Lake LBJ west of Austin, could save $4 million by discharging its effluent into the lake rather than installing the infrastructure needed for land-based wastewater treatment, according to city Mayor Frank Reilly.
Reilly called it an environmentally wise use of the treated sewage because it would go back into the water supply.
"It reuses something valuable, which is in short supply," he said. "It stops the waste of the water."
But opponents of the proposal, including affected property owners, several Austin-area legislators, the Sierra Club and the Lower Colorado River Authority -- which sells water from the lakes -- say the added waste would ruin the pristine water.
Ray Gay, 75, said he's already thinking about moving away if the TCEQ lifts the ban, which could take up to a year or longer.
Gay pumps his household water, up a long snaking pipe, straight from Lake Travis on the edge of his property. Using minimal filtration and reverse osmosis treatment, he and his wife Barbara drink it, bathe in it and wash their dishes with it. When the grandkids come over, they swim in it, too.
"No matter how much they treat it, it still changes the way the water tastes. They can't take everything out of it," said Gay, who lives in the tiny Village of Volente on the shores of Lake Travis. "I think I would want to move from here."
The Highland Lakes, spread across a wide expanse of the Texas Hill Country near Austin, include Lakes Travis, Austin, Buchanan, Marble Falls, Inks and LBJ.
The state prohibited the discharge of wastewater effluent, the liquid byproduct of raw sewage treatment, into the lakes in 1986. A handful of existing plants in operation at the time were exempted from the rule and discharge relatively modest amounts into the lakes.
A single wastewater plant is allowed to discharge 6,000 gallons a day into Lake Travis, according to the LCRA. If the ban is lifted, 33 additional plants would be allowed to discharge up to 7 million gallons a day into the lake, whose clear waters are a big draw for scuba divers, fishermen and recreational boaters, river authority figures show.
The LCRA said the wastewater would change the character of the water without doing much for the overall water levels. It would add just five inches to Lake Travis, which is about 33 feet below full.
Meanwhile, water quality experts say the effluent has high amounts of phosphorus and nitrogen, elements that can't be cheaply removed from human waste. These "nutrients" will cause algae blooms, decreasing water clarity and creating odor and taste issues for the drinking public, they say.
"It looks bad, it smells bad and it makes the water cloudy," said Lonnie Moore, president of the Protect Lake Travis Association. "It would certainly dampen your enthusiasm for drinking it or swimming in it."
Three TCEQ commissioners appointed by Republican Gov. Rick Perry will decide the fate of the request to lift the effluent ban. Staffers at the TCEQ, the state's lead environmental agency, are recommending that the issue undergo further study by a special panel of interested parties in the region.
Even if the commissioners give a preliminary green light to lifting the ban on Wednesday, it would take months or longer to implement new rules and conduct public hearings, officials say.