Cherrapunji town in the Meghalaya state of India is credited as the second wettest destination on Earth, having one of the world’s highest average annual precipitation rates around 11,777 millimetres (463.7 in) (Appendix A, Graph 1). The region is affected by the southwest monsoon, coming from the Bay of Bengal, which begins blowing in May and continues until September. Despite the heavy rainfall,
the locals still suffer from water scarcity during the winter months. Due to increasing deforestation and lack of vegetation in the area, maintaining the amount of rainwater in the soil gradually becomes harder every year, resulting in a shortage of drinkable water. Also, the available fresh water is contaminated due to pollution and state’s omission of maintaining healthy water supply systems. In order to offer a constant supply of clean drinking water to the locals of Cherrapunji, we propose the adoption of rainwater harvesting system to take advantage of the excessive rainfall by installing large tanks that will each serve a certain number of households. Rainwater harvesting system is a process of collecting rainwater in a catchment area, filtering to eliminate debris, dirt and dust, storing and using for various purposes. Considering the annual rainfall patterns in the area, we intend to build harvesting tanks that have the capacity to store enough rainwater during the rainy monsoon season. Rainwater is pure in terms of salts, minerals and chemicals, making it convenient for use as drinking water. However, installing filtration and purification equipment is essential to remove possible pollutants and contaminants such as algae, insects, dirt, air pollution, organic matter and animal or bird excrements. Cherrapunji has a population of 11,000 as of 2011 and there are around 2200 households in the region. According to these numbers, each of the rainwater harvesting tank is intended to serve 150-200 households scattered within a boundary of 2 km2 around the tank. The tanks will fill up with rainwater during the monsoon season when there is heavy rainfall and the water will be stored in order to be available for usage during winter months when water scarcity reaches its peak. The locals will be provided with a continuous supply of pure drinking water, within walking distance from their homes. The tanks will have a number of faucets to eliminate long queues and to ease people’s access to fresh water. People who fill empty buckets with water will be provided with carts to carry the water from the tank to their homes in the most convenient manner.
