Rooftop rainwater harvesting
Topic: Water Resources of India: Availability, Use and Conservation · NCERT: Class 10, Ch 3 "Water Resources"
Meaning
Rooftop rainwater harvesting means collecting the rain that falls on a roof. Pipes carry it through a filter of sand and brick into a sump (an underground tank) for use. Extra water can be sent into wells or pits to recharge groundwater. It is cheap and eco-friendly, and it raises water tables. It also eases pressure on city supplies and reduces runoff and flooding. Traditional versions exist, such as the underground taankas of western Rajasthan.
Example
In Gendathur village near Mysuru, Karnataka, about 200 homes harvest roof rain. Each home collects about 50,000 litres a year from about 1,000 mm of rainfall. Tamil Nadu was the first state to make rooftop harvesting compulsory for all buildings (2001-03), with penalties for those who do not comply.
Don't confuse with
- Watershed management: it covers a whole drainage area, including land, water, plants and people, through check dams and tanks. Rooftop harvesting works one building at a time.
Related concepts
- Rainwater harvesting
- Shillong rooftop rainwater harvesting
- Tamil Nadu rainwater harvesting mandate
- Watershed management
- Check dam
- Percolation tank
- Haryali
- Ralegan Siddhi
- Arvary Pani Sansad