Enter the harvested water (gal) and the rainfall depth (in) into the Calculator. The calculator will evaluate the Catchment Area.

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## Catchment Area Formula

CA = HW / RFD / .623

Variables:

- CA is the Catchment Area (ft^2)
- HW is the harvested water (gal)
- RFD is the rainfall depth (in)

To calculate the Catchment Area, divide the harvested water by the rainfall depth, then divide the result by .623.

## How to Calculate Catchment Area?

The following steps outline how to calculate the Catchment Area.

- First, determine the harvested water (gal).
- Next, determine the rainfall depth (in).
- Next, gather the formula from above = CA = HW / RFD / .623.
- Finally, calculate the Catchment Area.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem : **

Use the following variables as an example problem to test your knowledge.

harvested water (gal) = 45

rainfall depth (in) = 34