Heat waves are getting longer. Cities face floods one season and water shortage the next. Climate policy is no longer just a file in the Secretariat. It is about fixing drains, cooling classrooms, saving wetlands and helping communities earn by protecting nature. In Tamil Nadu, most of this work is managed by the environment, climate change and forest department.

Supriya Sahu, Additional Chief Secretary, Environment, Climate Change and Forest Department, Tamil Nadu, has played a key role in shaping the state’s climate work. From setting up the Tamil Nadu Green Climate Company to promoting cool roofs and restoring mangroves, she has focused on action on the ground. During The Energy and Resources Institute’s World Sustainable Development Summit 2026, she spoke to Responsible Us about turning plans into real projects, involving local communities in carbon markets, and preparing Chennai for a hotter and wetter future.

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The TNGCC model is seen as a strong special-purpose vehicle. How can other states move from policy on paper to real projects?
We designed a single-purpose vehicle that works only on the climate. Usually, climate work happens across many departments. There are also several national and international partners involved. When so many actors are working, the question is how to channel and align all the efforts in one place. The Tamil Nadu Green Climate Company was created as a special-purpose vehicle to bring all climate work under one umbrella. It is registered as a Section 8 company under the Companies Act. That means it is a not-for-profit company, but it is wholly owned by the government.

It is a strong model because all key departments are represented on its board. So when decisions are taken, everyone is aware. It avoids departments moving in different directions. The idea is to align efforts and make climate action more effective and grounded in implementation.

You spoke about tapping into carbon markets to fund the wetland mission and mangrove restoration. How do you ensure local communities benefit directly?
I have always said natural resources cannot be commodified without caution. Commodification is a danger and we must be very careful about it. Governments and communities must play the most important role because natural resources are assets of the community and the country.

So we are creating community structures. For example, 45 village mangrove councils have been set up and registered under the Societies Act. I always emphasise registration because it gives them legal status. Once they become legal entities, they are accountable and responsible. It also becomes easier for them to act within the framework of the law.

We are working closely with local communities and technical institutions like Indian Institute of Technology Madras, Sugandhi Devadason Marine Research Institute, and the United Nations Environment Programme. We also have partnerships with the World Bank. A major project supported by the World Bank is TN SHORE. All these partners coming together ensures that communities get the benefit of the projects being implemented.

How are you measuring impact?
Measuring impact is critical and not many people talk about it enough. Tamil Nadu Green Climate Company is responsible for monitoring and measurement. We have developed something called a project tracker. It is an online system with defined targets and milestones that must be achieved under each project. All implementing agencies are required to update it. So all the data comes to one central platform.

We are also engaging third party auditing agencies so that there is independent verification of the work being done. These are two important steps we are taking to ensure transparency and accountability.

The Cool Roof Project in Green Schools has been praised widely. How are you integrating passive cooling into building plans? Do we really need it?
In a warming world, cities are bearing the brunt because they lack green cover, have too much concretisation, dense populations and high emissions. So we need to both mitigate and adapt.

We are suggesting simple passive cooling solutions such as cool roofs, window shading and embedding proven technologies into building approval processes. In our state, starting with Chennai, we implemented a cool roof initiative in a low-cost housing society. We also implemented it in a government girls’ higher secondary school. We saw the temperature fall by 5 to 8 degrees in places where the cool roof was used.

Now we are working with city corporations and planning offices to include these simple cooling steps in building plans. The process is still on.

How is the state developing Chennai as a sponge city, keeping its floods and heavy rainfall in mind?
The first step is to hold on to rainwater. Chennai gets heavy rain, so we must store as much of it as we can. At least 72 sponge parks are being planned, and more than 21 have already been completed. These are small parks built to help rainwater soak into the ground instead of running off.

We are also restoring lakes and water bodies in and around the city. Ennore Creek is very important because it carries excess water from the city into the sea.. It has mangroves and supports fishing communities.

With support from the World Bank, several steps are being taken. We have set up a special project called the Manali Ennore Restoration Initiative. Under this, efforts include reducing water pollution, restoring water bodies and planting mangroves, to ensure the city becomes more resilient.

Give a message to our women leaders in the sustainability sector?
I think women are already taking leadership positions. I do not believe in just saying women must lead or women must be empowered. That has already been said, and it is important, but it is not enough.

It is time that more decisions are taken by women leaders and that more women are in decision-making positions. When women are empowered to take decisions, they can translate policy into action in a much more practical way. This has been my experience. They bring a certain insight that is sometimes difficult for others to comprehend.

That full 360-degree approach women can bring to policy is something we must acknowledge.