Rainwater Harvesting

Why rainwater?

Barefoot College believes that every drop of fresh water that falls on the ground, especially in developing regions, should be harnessed for use. Rather than wasting water that runs off rooftops and along streets, we combine traditional harvesting practices with new technologies to make water accessible, clean and safe to drink. We do not have to rely on hand pumps, wells, and unpredictable groundwater levels to provide potable water to hundreds of thousands of people in need.

Of all the water solutions that the College has tried and tested, rainwater harvesting has been the most sustainable and effective. Rainwater Harvesting (RWH) is a low cost method with maximum benefits. It provides clean, potable drinking water for villages, irrigates fields and sustains livestock—all important criteria for communities that depend on agriculture and animal husbandry.

How it works

RWH helps to replenish or rejuvenate groundwater levels directly as well as indirectly. While some methods of RWH (such as trenches, anicut, contour and dug wells) replenish groundwater levels by keeping rainwater on arable surfaces long enough to be absorbed naturally into the topsoil, other methods (like constructing RWH underground water tanks and small ponds) restore the water table by creating alternative water sources, thus reducing groundwater use for four to six months. This model is highly replicable in hilly, drought-prone coastal and desert regions of India, Sierra Leone, Senegal, Ethiopia, Mali, The Gambia and Afghanistan. The construction and implementation of RWH equipment is simple and inexpensive; it does not require assistance from outside contractors, and it can be tailored to each community’s unique geography and rural climate.

Rainwater collection begins by allowing surfaces to be cleaned naturally by the first rainfall of the season. Next, as rain continues to fall, gutter systems collect runoff and direct water flow into a sedimentation tank underground to separate additional toxins. Clean water is then pumped back up by hand so that nothing goes to waste.

Cost and impact

Since 2006, more than 20 collection tanks have been constructed. Nearly 1.5 million litres of fresh water have been made available to children during school hours. And more tanks are being constructed independently by community members who have passed on training to others. Even very arid regions that receive very little rainfall over the course of a year can still collect millions of litres of rainwater for sustained use throughout rainy and dry seasons.

On average, a 100,000 litre collection tank—complete with two low-cost, hygienic toilets built to encourage girls to attend classes—costs under $15,000 and can be constructed in less than five months. This estimate includes the cost of design, engineering, construction, training, travel and documentation. The cost of a litre of water comes to less than 5 to 10 cents. The average population of a village in Rajasthan is 1,000 people. Therefore, the average cost of constructing an RWH structure comes to approximately $10 per person. This individual investment of $10 provides the community with sufficient drinking water for four to six months each year. If the structure lasts 10 years, the cost will be $1 per person per year, and if it lasts 20 years, the construction cost will be fifty cents person per year. The community can continue to use the RWH tank even after it goes dry by refilling it with portable containers.

Rural communities have practiced rainwater harvesting for hundreds of years. Now, with new technologies adopted and implemented within a village, these communities can experience the lasting benefits of clean and accessible water sources.