This rain harvesting system is a commercial style system catching water from the roof, prior to discharge into the city's storm drain system. The rainwater is used for toilets and uses chlorine sanitation of the rainwater prior to use. The initial system was designed and built with a single rainwater above ground tank, due to the overwhelming success the following year the system was expanded to double the capacity by adding one additional tank. This system resulted in a 40% reduction in water use in this facility.