A rainwater harvesting system comprises components of various stages – transporting rainwater through pipes or drains, filtration, and storage in tanks for reuse or recharge. The common components of a rainwater harvesting system involved in these stages are illustrated here.
1. Catchments: The catchment of a water harvesting system is the surface which directly receives the rainfall and provides water to the system. It can be a paved area like a terrace or courtyard of a building, or an unpaved area like a lawn or open ground. A roof made of reinforced cement concrete (RCC), galvanised iron or corrugated sheets can also be used for water harvesting.
2. Coarse mesh : at the roof to prevent the passage of debris
3. Gutters:
Channels all around the edge of a sloping roof to collect and transport rainwater to the storage tank. Gutters can be semi-circular or rectangular and could be made using:
Locally available material such as plain galvanised iron sheet (20 to 22 gauge), folded to required shapes.
Semi-circular gutters of PVC material can be readily prepared by cutting those pipes into two equal semi-circular channels.
Bamboo or betel trunks cut vertically in half.

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