Rainwater Harvesting Yield

Annual gallons from catchment area, rainfall, and collection efficiency.

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Formula and source

Annual gallons = catchment_area_ft² × annual_rainfall_in × 0.6233 × collection_efficiency. The 0.6233 constant converts in × ft² to gallons (1 in × 1 ft² = 0.6233 gal).

ARCSA (American Rainwater Catchment Systems Association) Rainwater Harvesting Manual by name; NOAA precipitation data.

Audience

This tile is built for plumbers and the adjacent professions in the Cross-Trade Utilities group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.

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Posture

Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.