Water is an increasingly scarce resource. And not just in developing countries. According to the Environmental Protection Agency, at least 36 states will face water shortages by 2013.
At the same time, most of the water that falls out of the sky for free–rain, that is–just flows straight into the gutter. Why don’t we make better use of it?
Why, indeed. Researchers from the Natural Resources Defense Council (NRDC) recently profiled eight American cities and found that, depending on the city, rainwater collection systems on just half of the available rooftop space could supply between 21% and 75% of annual water needs. They would also save residents a combined $90 billion in municipal water fees. (As a bonus, rainwater collection also reduces the amount of polluted runoff that flows into lakes, rivers, and oceans.)
The NRDC based its model for each city on several factors including available roof area, annual rainfall, and local water rates. The $90 million figure assumes these eight cities have rainwater collection systems on half of their roof area, not all rainwater is captured because some storms dump more than the collection systems can handle, and captured rainwater isn’t all used immediately.”