In India, a predominantly agricultural economy, the small farmer still depends on the monsoons to sustain his crops. Yet much of this precious water is soon lost as surface run-off. While irrigation may seem the obvious response to this challenge, it has proved inordinately expensive the hence benefits only a privileged few. This has, in recent times, underscored the importance of Rainwater Harvesting as a low cost option.

The need for Rainwater Harvesting - Other Dimensions

• The alarming depletion and pollution of ground water
• Soil erosion resulting from unchecked water runoff
• The inadequacy of the urban water supply system to meet the demands of the burgeoning population.
• The hazards of consuming polluted water

Rainwater - The Immense Potential

Rain is the primary source of water in the hydrological cycle. Rivers, lakes and groundwater are all secondary sources. Having relied for centuries on these secondary sources of water, we continue to ignore the inherent value of the primary source of water - Rain.

Harvesting rainwater, today, has helped us rediscover the various utilitarian aspects of rain. This facilitates optimal use of rainwater at the site of rainfall.

Rainwater Harvesting - The Unbeatable Advantages

• Environment-friendly option
• Easy and simple means of meeting the water requirements in a variety of uses
• Mitigates the effects of drought
• Enhances ground water - both in quantity and quality
• Reduces water run-off, that could result in flooding of storm water drains
• Reduces flooding of roads and low-lying areas
• Reduces soil erosion
• Easy-maintenance and low-cost methods
• Results in considerable savings in water and electricity costs

Rainwater Harvesting - ANY ONE CAN DO IT!

Opportunities to Harvest Rainwater

• Rooftops of houses, public buildings, institutions, hospitals, hotels and shopping malls with wide open areas
• Farmlands, public parks, playgrounds etc.
• Paved and unpaved areas of layout, cities, towns and villages

Potential

Around 2,16,725 litres of rainwater can be harvested in an area of 2,400 sq.ft. (223 sq.mts. or a 40' x 60' site), taking into account the annual rainfall of Bangalore - 972mm / 38.26 inches (approx.). The harvest yield depends on the rainfall received, the catchment area and the collection efficiency.

Utilities

Harvested rainwater is stored in underground sumps or overhead tanks for subsequent use.

Harvested rainwater can also play a vital role in ground water recharge, through recharge pits, dug wells, bore wells, soak pits and recharge trenches.