Rainwater Harvesting

Rainwater harvesting is the accumulation and storage of rainwater for reuse before it reaches the aquifer. Uses include water for garden, water for livestock, water for irrigation, etc. In many places the water collected is just redirected to a deep pit with percolation. The harvested water can be used for drinking water as well if the storage is a tank that can be accessed and cleaned when needed.

Rainwater harvesting provides an independent water supply during regional water restrictions, and in developed countries is often used to supplement the mains supply. Rainwater harvesting systems are appealing as they are easy to understand, install and operate. They are effective in 'green droughts' as water is captured from rainfall where runoff is insufficient to flow into dam storages. The quality of captured rainwater is usually sufficient for most household needs, reducing the need for detergents because rainwater is soft. Financial benefits to the users include that rain is 'renewable' at acceptable volumes despite climate change forecasts, and rainwater harvesting systems generally have low running costs, providing water at the point of consumption (Ferguson 2012).

Benefits of widespread rainwater harvesting to the regional reticulated supply system may include reduced treatment, pumping, operation and augmentation costs, reducing peak storm water runoff and storm water processing costs, as well as reduced greenhouse gas emissions due to reduced dependence on pumping and potential augmentation through sources such as desalination (Coombes 2007, White, 2009).