Within a year and a half, the University of Texas will use reclaimed water in the cooling towers of the University’s Hal C. Weaver Power Plant. Eventually, the plan may extend to watering lawns and landscapes around campus.
Reclaimed water is highly treated wastewater that would normally go into the Colorado River. Some of this water is skimmed off, put into tanks and pumped around town through a series of pipes for non-potable or non-drinking purposes, said Dan Pedersen, manager of the reclaimed water program for the city of Austin. Construction of the pipes meant to disperse the water will begin in November or December and finish in January 2011.
"Essentially, the benefit of using the water is that you get to use water twice rather than UT using potable water just one time,” Pedersen said. “This kind of conservation definitely helps during times of drought."
Using the reclaimed water could allow UT to replace consumption of about 340 million gallons of potable water per year with the non-potable water, according to the utilities and energy management Web site.
"It’s a positive use of the water,” said environmental engineering professor Joseph Malina. “The reclaimed water program reduces the drain on the lake water. It’s a good way to keep campus green without having to use drinking water."
The process will take about 18 months and will cost about $1.6 million. The project saves the University money in the long run, said Juan Ontiveros, executive director of utilities and energy management.
Ontiveros said UT purchases two types of water from the city for use in the plant cooling towers. The University first uses free water that is captured condensation from air conditioning coil runoff for use in the cooling towers. Irrigation water and water used for drinking are purchased from the city.
UT pays $4.20 plus a $6.84 sewer charge per thousand gallons of drinking water. Irrigation water costs $4.20 per thousand gallons. UT hopes to replace the use of irrigation and domestic water with the reclaimed water that costs $1.03 per thousand gallons, Ontiveros said.
"The revenue is about 800 to 900 thousand dollars a year in savings that we will use to pay off this investment," Ontiveros said.
Austin has several thousand feet of pipes installed for reclaimed water and has been providing a reclaimed water service since 1974, Pedersen said, though that water went mostly to watering golf courses. Since the 1990s, the program has been remodeled with new facilities.
Pedersen said areas of Florida and California have used reclaimed water for years without any difficulty or problems. "If the water is used as intended, it’s not harmful," he said. "The only way it could be is if someone were to accidently drink it."
The city treats the water with chlorine and other chemicals that kill bacteria, Ontiveros said, but it’s not treated at the same level as drinking water. "We’re going to add even more chemicals to the water in our own towers. So we’re taking additional precautions on top of what is being done by the city. We don’t want to hurt anyone or damage any equipment."
Malina said reclaimed water is also safe to use for irrigation despite the fact that it may run off into creeks. "After the chemical analysis that the water goes through in the treatment plants, it may be better quality than the stuff in Lake Austin."
The new pipes carrying the water will run down Dean Keeton and Red River streets as well as Martin Luther King Boulevard and connect the University’s pipes to the city’s pipes.
"We’ve been anticipating the project for a long time, and it’s good to know we’re finally here," Ontiveros said. "The project is financially and environmentally sound because we’re cutting back on domestic water, which the city needs. Hopefully, it’ll delay the [city’s] construction of building another water treatment plant."
Get a daily look at what’s developing in science and technology throughout the world.