Rainwater Harvesting at the University of Georgia, Athens

From OnlineAthens comes a report about the University of Georgia’s latest water conservation project, a $600,000 cistern adjacent to the Tate Student Center. This is not the first cistern to grace the UGA grounds. The old ROTC building and the Paul D. Coverdell Building already had smaller cisterns. Several months ago, the university’s Ad-Hoc Task Force on Water Resources issued a report which describes the many measures the campus had been taking even before this current project began. Lee Shearer describes the latest addition to the campus:

The box is a giant cistern designed to collect rain and condensation from the building’s air conditioning system, and a real example of the kind of water-saving features UGA planners are including in new UGA buildings these days…The cistern is expected to save nearly a million gallons of water a year, which can be used to flush toilets in the Tate addition and irrigate landscaping beside the building.

The “box,” made of steel-reinforced concrete, is basically a 12-foot by 12-foot tank with a length of 70 feet. When fully operational, the massive collection system will claim an astonishing 95% of rainwater from the roof of the Tate Center and a nearby building. That adds up to a hefty 880,000 gallons per year, according to Holder Construction, which is also in charge of the overall student center expansion project.

At any given time, the cistern will be able to hold as much as 50,000 gallons of water, which will supply about half the building’s toilet-flushing needs, and also keep some of the landscaping green. This is especially important because in recent years, the University, long known for its picturesque beauty, has increasingly sacrificed aesthetics to the demands of necessity. Nobody likes to see brown lawns, so it is hoped that the latest effort to collect water will alleviate further need to under-hydrate the foliage. UGA feels strongly about its obligation to not only conserve water for its own sake, but as a publicly-supported learning institution, to set a good example and save the taxpayers’ money.

The other interesting part of this report concerns a new organization, a local chapter of Emerging Green Builders, which comprises not only students, but area professionals. A spinoff of the U.S. Green Building Council, the organization enables youth to become involved in green building in their own local environments, utilize the resources of the USGBC, and set up local events. To this end, Emerging Green builders sponsors an annual design competition and helps match up students and graduates to jobs.

In Architectural Graphic Standards, 11th Edition, the chapter on Plumbing includes a helpful chart of cistern types, categorized according to material, features, and cautions. Many factors need to be taken into consideration when designing a cistern, and this outline covers them all. AGS also lists on page 416 the reasons for the current interest in rain water collection:

• Escalating environmental and economic costs of providing water by centralized water systems or by well drilling.
• The relatively pure, soft, low-sodium water source that rain water harvesting offers.
• Health concerns over the source and treatment of polluted waters.
• A perception that there are cost efficiencies associated with reliance on rain water.

The last point is worthy of discussion. How is this working out? Is rain water harvesting cost efficient, or not?

SOURCE: ” Tate Center site showcases new water-saving cistern ” 04/16/08
photo courtesy of venkane , used under this Creative Commons license