University of North Carolina at Chapel Hill
IN-4: Innovation 4

Reclaimed Water System To reduce potable water consumption in our rapidly growing, drought-prone region, UNC Chapel Hill partnered with the local water provider, Orange Water and Sewer Authority (OWASA) to construct a reclaimed water system that became functional in 2009. This innovative partnership allowed UNC to fund development of the OWASA reclaimed water system by reserving reclaimed water capacity for UNC and enabling reclaimed water service to non-UNC customers in the future. Highly treated wastewater from OWASA is disinfected, stored, and pumped to campus where it is used for specific non-potable uses. Cooling tower make-up water for the University’s five centralized chilled water plants is by far the largest water use on campus, accounting for more than 200 million gallons of water per year. Three chilled water plants connected in the spring of 2009, and by the summer of 2010 the entire campus cooling load was met with cooling towers using reclaimed water. This reduced total potable water consumption at UNC by 25%. The reclaimed water is also used at the UNC Hospitals’ chiller plant (50 million gallons per year) and will be used for irrigation at the football stadium, the baseball stadium, and other athletic fields (10 million gallons per year). Reclaimed water will also be used to flush toilets in new buildings located near the distribution network, including the NC Botanical Garden Visitors Center and the Genomic Sciences Building. This $10 million investment by UNC will ultimately reduce total water demand on the community’s potable water supply by up to 10 percent and will allow OWASA to postpone the development of an additional water supply source. Given that the region experienced record 100-year droughts in both fiscal year 2003 and fiscal year 2008, UNC’s reclaimed water system will reduce the vulnerability of the hospital, the medical research facilities, the campus, and the town as a whole to future water shortages. The reclaimed water system has the additional benefit of reducing greenhouse gas emissions because distributing the reclaimed water to campus requires less pumping than obtaining, treating, and distributing potable water.