Explanation: Rainwater harvesting is a technique that involves the collection and storage of rainwater for various uses, such as irrigation, drinking water, and other domestic purposes. It is a sustainable practice that helps in conserving water and managing water resources effectively. Among the states in India, Tamil Nadu has been a leader in implementing rainwater harvesting policies.
Tamil Nadu has made rooftop rainwater harvesting structures compulsory for all houses. This policy was introduced to address the water scarcity issues faced by the state and to promote sustainable water management practices. The state government has implemented this policy through various regulations and guidelines, ensuring that all new constructions include rainwater harvesting systems. Additionally, existing buildings are also required to install these systems to comply with the state's water conservation efforts.
The policy in Tamil Nadu is unique because it mandates the installation of rainwater harvesting systems, making it a legal requirement for all houses. This approach ensures that a significant portion of the population is involved in water conservation efforts, contributing to the overall sustainability of water resources in the state.
In contrast, other states like Andhra Pradesh and Karnataka have also promoted rainwater harvesting but have not made it compulsory for all houses. These states have implemented various initiatives and incentives to encourage the adoption of rainwater harvesting, but they have not enforced it as a legal requirement like Tamil Nadu.
West Bengal, on the other hand, has not made rooftop rainwater harvesting compulsory for all houses. While the state has recognized the importance of rainwater harvesting, it has not implemented a policy that mandates its installation in all houses.
In summary, Tamil Nadu stands out as the only state that has made rooftop rainwater harvesting compulsory for all houses, making it the correct answer to the question. This policy reflects the state's commitment to sustainable water management and conservation efforts.