A 2,000 sq ft roof in the Piedmont generates 1,200 gallons per inch of rainfall. NC averages 45 inches annually — that's 54,000 gallons flowing into storm drains.
That's enough to irrigate a half-acre of landscape for an entire summer without touching municipal water.
Oversized cisterns create stagnant water that breeds mosquitoes and requires chemical treatment. Right-sizing prevents these problems.
The calculator matches cistern capacity to your actual irrigation demand, rainfall patterns, and roof catchment area.
North Carolina updated rainwater harvesting regulations, removing previous volume restrictions for non-potable use.
Stop losing free water. The calculator outputs optimal cistern size, first-flush diverter specs, and overflow routing for your property.