Development of rainwater harvesting technology for securing domestic water supply in Ibadan, Nigeria

Abstract

In both rural and urban areas, supplying adequate water to meet increasing population water demand is a major challenge faced by decision-makers in developing countries like Nigeria. This is as a result of the failure of conventional or municipal water supply systems to meet the challenges of providing clean water for the populace. People result to digging shallow and deep wells indiscriminately to supplement their daily water needs. As a result, the groundwater table would have been falling, causing hydrological imbalance. Domestic Roof-water Harvesting (DRWH) and groundwater recharge provide innovative solution to the inadequate water supply. In this study, a complete RWH technology was designed and constructed for a household, where public water system was non-existent. The RWH technology was incorporated into the existing shallow well water system. Water samples from the RWH system and shallow well were analysed using standard methods. With roof area of 70 m 2 , 21 m 3 reservoirs was required for dry period. The Hardness, Alkalinity, Chloride, Iron and Nitrate of the harvested water showed values of 20.0, 21.0, 15.0, 0.2 and 2.0 mg/l respectively while pH was 6.8. The values were below WHO guideline limits for drinking water. Safety measures were taken to ensure that the harvested rainwater was of good quality. The study revealed that RWH technology is a viable and reliable water supply option in both urban and rural areas for domestic purposes.