SUSTAINABLE OASIS TOOLS
Rainwater Harvesting Calculator
Estimate how much rainwater a roof can collect based on catchment area, rainfall and expected collection efficiency.
Use this tool to size storage tanks, compare sites and build a water resilience baseline before field measurements begin.
INPUTS
Describe the catchment system.
Formula:
Roof Area
×
Rainfall
×
Collection Efficiency
=
Collected Water
WATER COLLECTION
Rainwater Forecast
ESTIMATED
Water Metric
Value
Unit
Status
Theoretical Collection
Before system losses
—
litres
L
water
RAW
potential
Usable Collection
After estimated losses
—
litres
L
captured
EST.
calculated
Data status: ESTIMATED
Compare later with measured tank inflow.
CONTROL ROOM
Send collected water to the Control Room
The estimated captured volume can be transferred to:
water.collectedLitres
It remains classified as ESTIMATED until verified with real measurements.
WATER RESILIENCE
Every roof can become infrastructure.
A roof is not only shelter. With gutters, filtration and storage, it becomes part of the Oasis water system.
Capture
Convert roof surface area into potential water collection.
Store
Size tanks around actual rainfall and expected consumption.
Reuse
Direct suitable water toward irrigation, cleaning and other non-potable uses.
Measure
Compare predicted collection with actual tank inflow and seasonal performance.