Q2(b). Write an account on Water Harvesting Techniques.

Water harvesting is the collection, storage and efficient use of rainwater, runoff or groundwater to overcome water scarcity and ensure sustainability. It is essential in India due to erratic monsoons and over-exploited aquifers.

Major Water Harvesting Techniques

1. Rooftop Rainwater Harvesting

Rainwater collected from roofs into tanks or recharge pits. Mandatory in cities like Chennai and Gurugram.

2. Surface Water Harvesting

• Check-dams
• Farm ponds
• Percolation tanks
• Contour trenches

These structures reduce runoff and enhance groundwater recharge.

3. Traditional Systems

• Johads (Rajasthan)
• Kunds (Thar desert)
• Baolis (Delhi, Haryana)
• Khadins (Jaisalmer)
• Ahar–Pyne (Bihar)

4. Watershed Development

Integrated soil and moisture conservation using bunding, terracing and vegetative cover. Exemplified by the successful Hiware Bazar watershed model in Maharashtra.

5. Urban Water Harvesting

Bioswales, recharge wells, stormwater drains to reduce urban flooding and replenish aquifers.

Under the Mera Pani–Meri Virasat scheme, Haryana promotes farm ponds and recharge pits to restore groundwater in over-exploited blocks.

Water harvesting strengthens water security, supports agriculture, and mitigates drought risk.