Rainwater harvesting back in fashion
Nadia Al-Sakkaf (author), Sabrina Faber (photographer)
Twenty-five homes in Sana’a will benefit from a 75,000 Euros rainwater harvesting project, one of three winning project ideas of the Philips Livable Cities Award 2010/2011.
The warning that Sana’a could potentially be the first capital city in the planet to run out of water was the driving force behind Sabrina Faber’s, the principal for the Rainwater Aggregation in Sana’a (RAINS), project.
Through her scheme, Sabrina hopes to help solve the water shortages commonly experienced in the city during dry spells, whilst providing clean drinking water. This could potentially result in significant health benefits for the whole population.
The Philips Livable Cities Award was a global initiative designed to generate innovative, meaningful and achievable ideas to improve the health and well-being of city-dwellers across the world and make cities more livable for residents.
“Through their projects, the winners aim to improve the day-to-day lives of citizens in their respective communities. By enhancing livability on a local level, small-scale projects like these have the ability to change and enhance the lives of local inhabitants,” said a statement from Philips Livable Cities Awards committee.
Sana’a was one of three cities to have won the award last year, alongside Buenos Aires in Argentina and Kampala in Uganda.
Sabrina argues that for thousands of years, Yemenis used cisterns to harvest rainwater in mountaintop villages, and terraces to slow, spread, and sink rainwater and then cultivate land on rugged mountainsides.
During two distinct annual rainy seasons, the city of Sana’a and its surrounding basin receive an average of 200 mm per year of rainwater; other areas in the Yemeni highlands, where the bulk of Yemen’s population continues to live, receive up to 800 mm per year. If captured, those amounts could translate into millions of liters of clean water for use by inhabitants.
“Yet, within the last half-century, Yemenis have nearly abandoned the age-old practice of harvesting rainwater,” she said.
The RAINS project seeks to restore the ancient Yemeni technique of rainwater harvesting with a modern, innovative twist to produce a system capable of capturing from 10,000 to 100,000 liters a year per structure (capacity is dependent upon rainfall, rooftop area, and the system storage capacity).
The system works by utilizing Yemen’s existing flat roofs to capture rainwater, funnel it to a storage tank, and then directly consume that water for garden or external use. Faber, a development aid worker who has lived in Yemen for over twelve years, is using her Philips award to implement 25 to 50 pilot RAINS systems throughout the capital city, in private homes and public facilities.
“The first time I thought about this idea when I was hiking with my husband through the surrounding countryside of Sana’a. We saw firsthand how Yemenis collected rainwater in cisterns and terraces,” said Faber. “We realized that every time it rained in Sana’a, the rainwater had nowhere to go. The gift from the heavens was falling on Sana’a without any purpose. The water would either flow out of the city through a major, paved flood channel, or evaporate.”
Thus, more than a year ago, she and her husband implemented a prototype for the RAINS system at a site in Sana’a. During the testing phase last summer, in the space of less than 24 hours, and with only two days of heavy rains, the prototype, which has two above- ground storage tanks, accumulated over 10,000 liters of rainwater.
That rainwater was and is used to irrigate the facility’s garden. It also serves as a backup water supply for the building in the event that city water is not flowing, and thereby reduces the dependence on water obtained from unlicensed wells, the rapid spread of which is helping to deplete Sana’a’s water supply.
If you are interested in RAINS or want to find out more information contact Sabrina Faber at [email protected]