USVI Cistern Capacity Calculator
Virgin Islands homes catch their own water. Enter your roof size to see the cistern the building code requires — and how much rain that roof actually harvests.
Code minimum: 10 gallons per sq ft of roof for single-story, 15 for two or more stories. Harvest: roof sq ft × rainfall inches × 0.623 gallons. A water-delivery truck is roughly $400 for ~3,000 gallons in a dry spell (varies). Source: V.I. building code (Title 29 §308) & UVI/DPNR rainwater guidance. Figures as of June 2026 — confirm current code with DPNR.
Estimate only. Actual cistern requirements depend on your specific plans, roof geometry, and current code; rainfall varies by year and location. Confirm with a licensed USVI engineer or DPNR before relying on these figures. At Home Real Estate, LLC.
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