Thazhambur Lake restoration brings fresh lease of life to the area

Water body rejuvenation

thazhambur lake bund
The Thazhambur lake is spread across 30.6 heactares. Pic: Care Earth Trust

I remember being on the school bus, on the way to school and looking out the window on the final stretch to see a large and empty ground. I did not concern myself with its origin, assuming that it was a wasteland. Then, one day, I noticed some activity taking place on this wasteland. I could not make out what was happening. Till one day, a great change took place: the land was suddenly blue with water! This ‘great change’ did not take place in a day, of course; the project that transformed the land and restored the original water body took over two years – from 2018 to 2020. 

The land I am referring to is the Thazhambur Eri (lake), located in Thiruporur. The area had been designated a lake by the Public Works Department. Care Earth Trust, a Chennai-based biodiversity, restoration and conservation-focused organization played the primary role in the restoration of the eri. The effort was funded by Hinduja Leyland Finance’s “corporate social responsibility” initiative, the Jal Jeevan Program

Working on the Thazhambur Lake

The project kicked off with a thorough ecological survey of the land. The team began with a topographical study of the place, which was followed by a lake bed bathymetry study, to determine the scale of dredging and desilting that would have to be taken on. 

Bathymetry Study: The measurement of the depth of water in oceans, rivers or lakes. 

Catchment Area: The area of land from which water flows into a river, lake or reservoir.

Recharge Wells: Usually a precast concrete ring lined structure, typically a metre or 1.5 metres in diameter and going to a depth of 3 to 8 metres, a recharge well takes water run-off from rooftops, paved areas and roads, filters it and sends it underground to increase the water table.

“The team soon realised that the lake bed was severely compromised, it had been dredged indiscriminately and there were also instances of siltation,” said Dr. Jayshree Vencatesan, trustee of Care Earth Trust.

The aim of the exercise was to restore the lake, strengthen its boundary wall, and increase its water holding capacity. The original capacity of the eri was estimated to be 16.46 million cubic metres.

Following the study, almost 1,40,000 cubic metres of earth was cleared from the area and then used to build a superstructure bund (about 2000 meters in length) for support.  Over the first year of work, the bund was further compacted. Native plants and trees were planted on the surface of its periphery, which began to double as a walking path. Following the clearing of the land, the inflow channels were cleaned to ensure that the eri receives water from the catchment area. 


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Fruits of restoration efforts of Thazhambur Lake

These efforts have resulted in the total recovery and restoration of 30.60 hectares of water spread area, consolidation of 1200 meters of bunds and restoration of 1200 metres of canals leading in and out of the wetland. The wetland holding capacity has increased by 5.6 million cubic feet of water over the existing capacity of 16.46 million cubic feet.

The water level of the eri has remained the same over the monsoons since the project was completed. Five recharge wells have been established in the lake bed area, and these are effective in ensuring that the groundwater table remains stable. Within a 6-kilometer radius of the lake, all the borewells can get freshwater due to this restoration work. 

Manjari Srinivas, a teacher at The School, Krishnamurti Foundation of India (KFI), recalls that earlier, by February every year (after the monsoons), the lake bed would be dry. Now, the water level is constant, and the rains don’t affect the school as much. The weather has also gotten cooler in the areas around the lake. Siddharth Madhavan, a student of Class 12 at The School, KFI,  likes to cycle around the eri. “The sunset on the lake is beautiful,” he said.


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Flora and fauna around Thazhambur Lake

In the water-holding area, five artificial islands have been created for birds to nest. Strong trees have been planted on these islands so that the birds are comfortable. “After the restoration, there have been a number of birds which have colonized the eri,” said Dr. Vencatesan. Murals depicting the biodiversity of the eri have been painted and displayed. There are mud huts that have installations of informative tablets for visitors to view. 

Pradeesh U, a teacher at The School, KFI, said that he has seen a lot of birds around the lake — Shikras, Woodpeckers, Kingfishers, Cuckoos, Waterhens, Drongos, and Bee-eaters — and that their presence makes the area lively.

In the hope of generating more awareness and enabling participation, “Live Labs” have been created. “Live Labs” are huts with installations, information panels and equipment that help children and adults learn about wetland ecology, the biodiversity of the eri and the science behind eco-restoration. The models and panels explain various processes, from plant science to drainage patterns. 

Thazhambur lake area
The restoration has helped provide a source of water to surrounding areas. Pic: Care Earth Trust

They have also planned an 8-Session Curriculum for the students of eight schools located near the eri. The curriculum encapsulates wetland ecology to enrich the school children’s knowledge. The curriculum has been developed with the help of the local schools so they can together find a holistic path to generate more awareness among the children. 

Little did I know when I looked at the blue expanse of water that so much effort had been put into restoring this lake. We are fortunate that the work has yielded significant improvements to the local surroundings, and more importantly, restored an important life support system of the Thazhambur ecology. 

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About Maitreyi Bharath 1 Article
Maitreyi Bharath is a student of class 12 at The School, KFI. She wrote the article during her time as an Environmental Science intern at Care Earth Trust.

6 Comments

  1. It’s wonderful to find children so aware of our ecology. Great in-depth writing Maitreyi Bharath..

  2. I hope with restoration the waste dump yard will be cleared. The amount of waste dumped near the lake is a grave threat just not to the residents but also to the lake and the forest area. It’s a big health hazard. Hope the authorities are able to clear the dump yard.

  3. I am also passing through the lake everyday its a beautiful view and enjoyable moment while crossing the lake. I would like to bring your notice that drainage water is being discharged in rainwater canals near Thazhambur koot road (opposite to Adroit District Apartments) and also near the hostel of Agni Institute of Technology. If it’s allowed to continue, soon it will pollute the lake. Authorities concerned and social activities may take steps to prevent it at the initial stage.

  4. Nice and good Article by a 12th std boy.
    I work in siruseri in a IT company .I used to go by this lake in the prepandemic days and used to look at it.I observed an opening in the lake near thazhambur and could flood the area.proper checkdam or barge should be constructed

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