Brief Notes on Water Conservation


Water being one of the most precious and indispensable resource needs to be conserved. The following strategies can be adopted for conservation. The following strategies can be adopted for conservation of water:

(i) Decreasing run-off losses:

Huge water loss occurs due to run-off on most of the soils, which can be reduced by allowing most of the water infiltrate into the soil. This can be achieved by using contour cultivation, terrace farming, water spreading, chemical treatment or improved water storage system.

(a) Contour cultivation is done on small furrows and ridges across the slopes which trap rain water and allow more time for infiltration. Terracing constructed on deep soils has large water storage capacity.

(b) Conservation-bench terracing involves construction of series of benches for catching the run-off water.

(c) Water Spreading is done by channeling or lagcoon-levelling.In channeling; the water flow is controlled by series of diversions with vertical intervals. In lagoon leveling, small depressions are dug in the area so that there is temporary storage of water.

(d) Chemical wetting agents (surfactants) increase the water intake rates when added to normal irrigated soils.

(e) Surface crop residues tillage, mulch animal residues etc. help in reducing run-off by allowing more time for water to penetrate into the land.

(f) Chemical conditioners like gypsum (CaS04 2H20) when applied to sodic soils improves soil permeability and reduces run-off water.

(g) Water storage structures like farm ponds, dug-outs etc. build by individual farmers can be useful for measures for conserving water through reduction of run-off.

(ii) Reducing evaporation losses:

This is more relevant in humid regions. Horizontal barriers of asphalt placed below the soil surface increases water availability and increases crop yield by 35-40%. This is more effective on sandy soil but less effective on loamy sandy soils.

(iii) Storing water in soil:

Storage of water takes place in the soil root zone in humid regions when the soil is wetted to field capacity. By leaving the soil fallow for one season water can be made available for the crop grown in the next season.

(iv) Reducing irrigation losses:

(1) Use of limited or covered channels to reduce seepage.

(2) Irrigation in early morning or late evening to reduce evaporation losses.

(3) Sprinkling irrigation and drip irrigation to conserve water by 30-50%.

(4) Growing hybrid crop varieties with less water requirement. .

(v) Reuse of Water:

(1) Treated waste water can be used for fertile- irrigation.

(2) Using grey water from washings, bathtubs etc. for watering gardens, washing cars or paths help in saving fresh water.

(vi) Preventing wastage of water: This can be done in households, commercial building and public places.

(1) Closing of taps when not in use

(2) Repairing if any leakage from pipes.

(3) Using small capacity flush in toilets.

(vii) Increasing block pricing:

The consumer has to pay a proportionately higher bill with higher use of water. This helps in economic use of water by consumers.