Short essay on Rainwater Harvesting Rural area

The people in rural India have used a large number of water collecting methods to capture as much rainwater as possible which had fallen on their land. Some of the methods used for water harvesting by the rural people (or farmers) were: Digging of small pits and lakes ; Building of small earthen dams (or embankments); Construction of dykes (long walls of earth to trap water); Construction of sand and limestone reservoirs; and setting up of roof-top water collecting units. All these methods of collecting and saving rain water have recharged the depleting groundwater levels.

Rainwater harvesting is an age-old practice in India. Water-harvesting techniques used depend on the location where it is to be used. Some of the ancient ‘water harvesting structures’ used in different rural regions of our country (which are still in use) are given below:

Region

1. Rajasthan

2. Maharashtra

3. Madhya Pradesh and Uttar Pradesh

4. Bihar

5. Himachal Pradesh

6. Jammu region

7. Tamil Nadu

8. Kerala

9. Karnataka

Ancient water harvesting structure

Khadin, Tanks, Nadis

Bandharas, Tals

Bhundhis

Ahars and Pynes

Kulhs

Ponds

Eris (Tanks)

Surangams

Kattas

We will now describe a traditional rainwater harvesting system for agriculture called khadin which is used in Rajasthan. The main feature of khadin system of rainwater harvesting is a very long (100 m to 300 m long) earthen embankment called ‘blind’ built across the lower edge of the sloping farmland. The rainwater from catchment area flows down the slopes and stopped by the bund to form a reservoir.

The excess water flows across the bund through sluiceways (or pathways) provided for this purpose and goes into shallow wells dug behind the blind. The rainwater which collects in the reservoir formed by the bund, and in the well, seeps slowly into the land (or ground). This water-saturated land is subsequently used for growing crops.

Please note that the main purpose of water harvesting is not to hold rainwater on the surface of the earth but to make rainwater percolate under the ground so as to recharge ‘groundwater’. The various advantages of water stored in the ground are as follows:

(i) The water stored in ground does not evaporate.

(ii) The water stored in ground spreads out to recharge wells and provides moisture for crops over a wide area.

(iii)The water stored in ground does not promote breeding of mosquitoes (unlike stagnant water collected in ponds or artificial lakes).

(iv) The water stored in ground is protected from contamination by human and animal wastes.

(v) The water stored in ground is utilised for the benefit of local population.

Rainwater harvesting in rural areas not only increases the agricultural production and income of the farmers but also mitigates (makes less severe) the effect of droughts and floods, and increases the life of downstream dams and reservoirs.