Situated in a region dominated by summer monsoon, Nepal receives about 80% of its annual precipitation in the summer monsoon season. With increasing rainfall variability in recent years, the Karnali River Basin in western Nepal has been experiencing increasing incidents of drought, making it more vulnerable to a changing climate. To improve the people’s adaptive capacity and manage available water resources for household use, different approaches have been initiated. Among them, rainwater harvesting is considered as an effective and efficient method, which can be implemented and managed locally. Rainwater harvesting is the approach of collection and proper utilization of the rain using collection tanks. However, the communities are using this approach traditionally without considering any prior information on rainwater harvesting systems. To address this situation, an Android-based application “Aakaashepani” was developed as a decision-making tool for installing household level rainwater harvesting systems.
Aakaashepani (आकाशेपानी) is a user-friendly and interactive Android application that provides an enabling environment for the installation of a rainwater harvesting system. With the help of this application, users can calculate the optimal tank size required for household need in a few easy steps with their fingertips. In addition, it maps the nearest vendors from where people can purchase the installation parts and provides other technical and financial aspects of rainwater harvesting systems specific to the household site. This application incorporates the information of local precipitation pattern, structures and dimensions of roofs and their runoff coefficients including households’ water requirements. The algorithm of the application dynamically adjusts to the users’ input considering the water availability, demand and potential storage. This application is currently limited to Karnali River Basin, Nepal, but, being freely available and highly customized to the local context of the Himalayan basin, it is of great significance to build adaptive capacity of the local people. The application (Android version only) is available at https://play.google.com/store/apps/details?id=com.rwh.app