Abstract: Rainwater run-off from a roof or other structure may be collected via a system of gutters and downspouts for delivery via gravity to a collection pipe, then via gravity to a connective pipe, and then via gravity to a filter system where the collected rainwater may be filtered and then delivered via gravity to one or more storage tanks When needed, the filtered rainwater may be pumped from the storage tank(s) via a distribution system to an irrigation system or other destination. The distribution system may include a hydropneumatic water tank and a centrifugal filter. If the storage tank(s) is/are empty, then an empty indicator may cause water from a water supply source to be used to irrigate instead of the filtered harvested rainwater.