The collection of rainwater for future use and also to increase the ground water level is called as rainwater harvesting. Rainwater harvesting is commonly done by collecting the rainwater that flows on the rooftop for later utilization. Here is the rainwater harvesting calculator which calculates the rainfall harvest based on the roof area, amount of rainfall and collection efficiency. Rainfall harvest calculation is essential to ensure the efficiency of the project.
A roof area of 30 cm2 having a rainfall amount of 8 cm and collection efficiency of 0.9.
Rainwater Harvesting = 30 x 8 x 0.9
= 2.16 cm3