I've been thinking about this lately as well. This week we just installed a 275 gallon water tank to catch water from just a portion our roof (about 1,000 square feet of the roughly 10,000 square feet). We've had a fair amount of rain recently and in the four days we've had the tank, we've collected 500 gallons of water.
We installed the water tank so we could use the water for our rooftop garden, but after seeing how much water we have the potential to collect, I'm wondering if it's possible to use it for other purposes. We are working with a college student who is majoring in sustainability to write an official policy for us and investigate other sustainability initiatives. One thing I'm going to have her research is reusing rainwater. I'll let you know if we come up with anything.
