Counting Raindrops

How Many More Baths Can You Get From a Rainstorm?

Here are a couple of fun ways to calculate rainfall to quantify runoff or how much you could be harvesting.

USGS – The U.S. Geological Survey has developed a fun way to quantify the amount of water in gallons that could be captured from a rain event.

Plug in your yard area + the inches of rain.


The calculator will show you the number of gallons of rainwater AND inform you of how many more baths you can take if you harvested and stored that rainwater!  A useful tool for designers and fun for the designer’s kids!

BRAE provides a great tool on their website for measuring rooftop runoff and calculating the amount of water you COULD be harvesting from your roof.

Enter the physical address.  Google Earth will locate you (which is amazing itself!).

Trace the edges of your roof.


The calculator estimates the number of gallons that can be harvested from your roof based on local rainfall averages. 

What fun!  Thanks USGS and Brae!