Rainwater Harvesting at Sam's Club
The Sam's Club in Fayetteville, AR was used as a test site for many water-saving ideas. One of those ideas was rainwater harvesting, using approximately 2/3 of the rooftop as a harvesting area and providing approximately 72,000 gallons of storage capacity in two large above-ground cisterns. The harvested water was then used for irrigation of landscaping on the site, and as make-up water for the refrigeration system which used evaporation as a cooling method. The harvesting system was designed collaboratively with a large team of consultants - using 20+ years of local rainfall data, and calculated loads for the irrigation and refrigeration systems, we determined the optimum size of the capture area and storage capacity to provide the majority of the required demand, with the exception of the driest months of the year. In the dry months, water is automatically provided from the City mains when the cisterns are empty.