Steps and measures to conserve water in agricultural areas and in metropolitan cities

Introduction

Fresh water is scarce and its demand keeps rising. Farming uses the largest share of it, while large cities waste much of what they draw. Both need two kinds of steps: using less water for the same work, and catching and storing more of the rain where it falls. Reducing demand by saving water is more sensible than chasing ever larger supplies.

Conserving water in agricultural areas

1. Drip irrigation. Tubes carry water straight to the roots of each plant, so far less is lost to evaporation and run-off than in flood irrigation.
2. Choosing crops that suit the water available. Water-hungry cash crops such as sugarcane need enormous quantities of water; over-irrigated fields then become waterlogged and salty and stop yielding. Encouraging millets and pulses in dry districts saves water and land.
3. Watershed work on the slopes. Bunds along the hill slopes and plugs in small streams (nala plugs) hold back rain, keep moisture in the soil and let degraded land be re-vegetated.
4. Farm ponds and percolation tanks. Small tanks and rainwater harvesting on the farm store water for irrigation and recharge the wells.
5. Stopping losses in canals. Leaks from dams and canals waste a large share of irrigation water, so lining canals and repairing them is a direct saving.
6. Using treated waste water. Treated and recycled municipal waste water can irrigate fields in place of fresh water.
7. Charging for water. When water is priced at its real value, farmers use it more carefully.

Conserving water in metropolitan cities

1. Rooftop rainwater harvesting. Roof and terrace water is led into a covered tank and kept clean for use after the monsoon, or is sent down to recharge the aquifer below.
2. Fixing leaks. Leaking taps and pipes are a major loss in cities, and the pipes and canals that bring water from distant dams lose close to half of it on the way.
3. Recycling waste water. Treated sewage can be reused for parks, industry and nearby farms, so that fresh water is kept for drinking.
4. Metering and pricing. Paying for what is actually used curbs waste.
5. Saving water at home. Simple habits such as closing taps while brushing, using a bucket instead of a hose to wash a car and reusing kitchen rinse water on plants cut household demand.
6. Protecting lakes and open ground. Keeping city lakes, ponds and unpaved green areas lets rain soak into the ground instead of running off into drains.

Conclusion

In villages the biggest saving comes from efficient irrigation and from holding rain on the land; in cities it comes from harvesting rain, stopping leaks and reusing waste water. Together these steps can close much of the gap between demand and supply.