The Wildflower Center�s striking architecture is constructed to conserve resources. A central irrigation system collects rainwater from 17,000 square feet of roof, or about 10,200 gallons per inch of rain. The separate entry cistern is fed by 1,167 square feet of roof, collecting 700 gallons per inch of rain. Another cistern and ponds collect water for re-circulation. (via WRC site)
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