Abstract

This is a study of location specific rainwater harvesting techniques from the past to the present. To evaluate ancient methods of water harvesting/conversation, large scale experiments were laid out using essentially two modern methods: spreading and water injection. The spreading techniques comprised of slopes, trenches, ponds, percolation tanks, etc., whereas injection techniques comprised of augured piles, dug wells, injection of water through tube wells, roof water collection and pouring it into tube wells.

In an area of 250 hectares, slopes along roads, trenches in and around the cultivated fields of 2 to 3 hectares, small ponds in low lying areas, percolation tanks for small catchments were developed. Water recharge in the deep aquifer through such spreading techniques was found to contribute around 23 % of rainwater available for conservation. An innovative Indore technique was applied to abandoned dug wells by pouring in run off water. Round hole piles with a diameter of 22 cm and 2 to 3 m deep were augured and filled with pebbles and sand in places such as parking lots, gardens and empty areas. During the monsoon season when surplus clean water was available on the surface or in dug wells, water was injected in the tube wells up to a depth of 30 to 50 meters with the help of motor pumps. The deep aquifer accepted water to its full capacity. Abandoned tube well bores and dug wells were used for pouring collected roof water. All these injection techniques contributed 77% of artificially recharge ground aquifer.