Less than Twenty-Four Hours; More than 10,000 Liters‎

In less than 24 hours and with two heavy rains, we accumulated over 10,000 liters of rainwater for use ‎at an office in Sanaa. Using a prototype of the RAINS system, a rainwater aggregation project that recently ‎won the Philips Livable Cities Award water was collected from the flat rooftop between one August ‎Saturday afternoon to the following Sunday morning. ‎

The RAINS system is relatively simple: Ensure that the rainwater which falls on the flat rooftops of ‎buildings in Sanaa flows into pipes that are attached to water storage tanks, rather than just having ‎the water drain from pipes or water holes onto the street below and evaporate. To make the water ‎potable it can be filtered. For other uses, it can be pumped up to the rooftop storage tank or into ‎underground tanks (if these are available). At the current prices for a water truck (around YR 10,000 or ‎USD $40), each time the tanks are filled, that amount is saved.



These two tanks were filled in just two heavy rainfalls in under 24 hours. The water collected by these two tanks is stored in an underground storage tank that normally calls for one large water truck (wight or booza) to fill.



This system is a prototype still being assessed as the rainy season progresses. We are pleased with its ‎success, but it is likely that we would have collected even more water. This system does require ‎oversight in times of heavy rains. Late Sunday morning we noticed that our water storage tanks were ‎full and in fact overflowing which allowed a lot of water to escape unused to the pavement. We used ‎a hose to drain the water from the upper tanks to an underground tank which is directly connected by ‎a water pump to our rooftop tank, but the hose had a kink in it, causing water to back up and overflow ‎once the above-ground tanks were filled. Once the kink was sorted out, it took another twenty-four ‎hours to empty the 10,000 liters and fill up the underground water tank and the rains were still falling ‎in Sanaa. Imagine if every building and every house in Sanaa were doing the same!‎

Water is the source of life. Yet increasingly groundwater reserves in Yemen are dwindling and are not ‎easily or quickly replenishable. During the summer rains in Sanaa, hundreds of thousands of liters of ‎water can be seen streaming down streets and then eventually evaporating in the sun. Once water ‎hits the pavements it is no longer sanitary. Further, the rising cost of trucked, filtered, and bottled ‎water is making its cost prohibitive for many families in Sanaa and there is no guarantee that the ‎water is hygienic. The RAINS system proposes alternatives in water management. ‎

The RAINS concept is simple and it is a Yemeni solution practiced by generations of Yemenis until forgotten in the ‎urbanization and modernization process that focused on exploiting groundwater reserves rather than ‎relying on rainwater catchment. In Yemen’s countryside, empty cisterns sit disused, while diesel-‎powered pumps busily deplete Yemen’s dwindling groundwater reserves.‎

The RAINS project seeks partner organizations to help implement the system on a larger scale in ‎Sanaa. Interested parties should contact admin@planetecole.com. ‎