Rainwater Harvesting System Approach for Cikarang, Indonesia

Abstraksi

Rainwater harvesting (RWH) should be a good water source, as Indonesia is in the tropics, and has abundant rainfall. This research was aimed at identifying the ability of RWH system as a reliable water supply at the domestic level using building cost, water consumption and water quality as indicators. We built two individual and one communal RWH systems in Cikarang and recorded building costs, monthly water consumptions and trimester water qualities for each system over a period of November 2015 – August 2016. The results showed that on average, the cost of building an RWH system was approximately IDR 5 million (USD 362) for an individual system and IDR 29 million (USD 2,100) for a communal system. With a 1,010-litre water tank, an individual RWH system could not fulfil an individual household’s minimum water requirement, and households must top up water for at least 6 months when rainfall is lower. With a 10,000-litre water tank, a communal RWH system should be able to meet minimum water requirements, because it collected about 236 m3 water in a year, which could fulfil the 49.8 lpcpd requirement for 13 people who live in communal systems. However, they still had to buy water for 4 months, due to fluctuations in consumption patterns. The quality of sampled rainwater did not conform to drinking water standards, especially for total coliforms. However, the appearance of the water was clear and the taste was adequate such that some households consumed the harvested water after boiling.