Tamil Nadu has made rainwater harvesting compulsory for all houses in the state. This move was initiated in response to the severe water scarcity and drought conditions faced by the state. The government of Tamil Nadu recognized the importance of conserving water and implemented this mandatory policy to ensure sustainable water management.

The state government of Tamil Nadu enacted the Tamil Nadu Combined Development and Building Rules (TNCDBR) in 2003, which made it mandatory for all buildings to have a rainwater harvesting system. This law applies to all types of residential, commercial, and industrial buildings. The objective behind this regulation is to capture and store rainwater, which can then be used for various purposes such as domestic use, irrigation, and recharging groundwater.

Key Points:
1. The Tamil Nadu Combined Development and Building Rules (TNCDBR) enacted in 2003 made rainwater harvesting compulsory for all buildings in the state.
2. The law applies to residential, commercial, and industrial buildings.
3. The aim is to capture and store rainwater to address water scarcity and drought conditions.
4. Rainwater harvesting helps in sustainable water management and conservation.
5. The stored rainwater can be used for domestic purposes, irrigation, and recharging groundwater.
6. The policy is a response to the severe water scarcity and drought conditions faced by Tamil Nadu.
7. Tamil Nadu has been actively promoting rainwater harvesting as a means to address water scarcity.
8. The state government provides incentives and subsidies to encourage the adoption of rainwater harvesting systems.
9. The success of this policy has led to a significant increase in the number of buildings with rainwater harvesting systems in Tamil Nadu.

Overall, the mandatory implementation of rainwater harvesting in Tamil Nadu has been a significant step towards water conservation and sustainable water management. It has helped in addressing the water scarcity issues faced by the state and has encouraged individuals and organizations to actively participate in rainwater harvesting initiatives.