Some cities have looked at the possibility of stormwater harvesting only to conclude that, on a large scale, the investment required may not be equal to the benefits gained. That may be the case in arid or semi-arid climates, especially if you’re counting on harvesting to significantly reduce potable water use. But if you look at the problem on a much smaller scale, as a town in North Carolina is doing, you might find you have more water than you need, and for a relatively small investment.
The town of Wrightsville Beach recently installed cisterns to collect roof runoff from its municipal complex with fairly modest goals for using the water: washing the town’s fire trucks and supplementing landscape irrigation. The five 3,000-gallon cisterns have collected more water than the town can use for these purposes, so it’s installing a pumping mechanism to send the excess runoff to irrigate nearby soccer fields. At the same time, it’s planning to install additional cisterns, and it’s publicizing the project as it goes.
The original installation, done with the help of the North Carolina Coastal Federation, was intended to help reduce polluted runoff to local creeks and reopen them for shellfish harvesting. Now the Coastal Federation is leveraging the success of the project—and the public attention it’s getting—to encourage other lot-level measures that homeowners can take to reduce runoff.
There is likely a long-term benefit here much greater than the obvious one of reducing runoff. Some stormwater managers have said that one of the main advantages of rain barrels on residential properties is their educational benefit—they get people thinking about where rainwater goes and how to keep it out of the storm sewer system, even if the effect of the rain barrels to reduce overall runoff is relatively insignificant during a downpour. It’s a little bit like the issue of recycling: Years of very effective outreach campaigns have taught people that it’s the right thing to do; many now do it religiously and wouldn’t think of throwing an aluminum can or plastic bottle in the trash. When we reach a point where the cost of collecting recyclables separately from other wastes at least temporarily exceeds the benefits of doing so, do we tell people they should stop recycling for the time being? Not at all; we keep the momentum going.
In Wrightsville Beach, the benefit of the cisterns—which are of course much larger than the typical 50-gallon residential rain barrel, but still a fairly modest in terms of total runoff—and the related projects that result from them are likely to go far beyond irrigating soccer fields and washing fire trucks in the public discussion and support they generate.
Tuesday, September 03, 2013
By: Kaspersen, Janice: Stormwater Editor
Water Rhapsody South Africa has a few different rainwater harvesting systems; from schools to private homes. Harvest your water, store it in water tanks and make good use of it. Gauteng has a good rainfall.