Up until a few years ago, the Otteri lake inside Chennai’s Vandalur Zoo would witness thousands of migratory birds every winter. Flying in from the frozen lands of the Arctic Circle, these birds would call the picturesque lake their home for the next few months.
However, the number of birds being sighted became fewer and fewer in the past couple of winters, as Otteri lake inched toward a slow death. Battered by Cyclone Vardah in 2016, followed by consecutive summers of severe drought, the large lake dried up almost entirely.
The last nail in the coffin was perhaps the extreme drought of 2018 in Chennai. The Vandalur zoo or Arignar Anna Zoological Park was severely affected. While the zoo authorities had to outsource water to save the animals, the Otteri lake inside turned into a parched stretch of fallow. The lake was dead. And no birds came anymore.
Restoring Otteri lake
The rainfed lake spans over a sprawling 18 acres which, barring a few shallow marsh patches, went completely dry. Lying in the foothills of Vandalur hills, Otteri lake lies in a catchment area which needs a consistent recharging of water. The recurring droughts affected that possibility.
But, where there is a will, there is always a way – believes IFS officer Sudha Ramen, the Deputy Director of the Vandalur Zoo. Under the guidance of Director Yogesh Singh, Ramen set out with her team to revive the Otteri lake.
The work started in full swing in February 2019. Eight months later, in October 2019, the lake was brimming with water. Talking to The Better India (TBI), Ramen shares the endeavours that helped her achieve the seemingly impossible.
“The first task was to clear the natural drainage channels, followed by desilting. The soil was utilised to raise shallow mounds across the expanse of the lake, which we later afforested with fast-growing plants that attract birds,” says Ramen.
Trees like Barringtonia (freshwater mangrove), Arjuna, Jamun, Ficus were planted aplenty on these mounds, to be nourished by the monsoon waters. “To our immense surprise, almost all the mounds were submerged by rainwater this season, and the plants are thriving at their brightest green.”
Overcoming all challenges with team efforts
A major challenge was weed encroachment in a major portion of the lake. The proliferation of killer weeds led to eutrophication in the water-retaining zones of the lakes. It was a painstaking task to weed the vast area. Ramen hails the incredible efforts of her team, who worked on war-footing to perform the daunting work. She specifically mentions the contribution of Range Officer Uma, Forester Kumar and the official staff of the Vandalur zoo.
After restoration, the lake’s storage capacity has increased subsequently. In addition, bunds and weirs have been raised around the area to prevent the lake from drying out. Several percolation ponds and rainwater storage units have also been dug out across the zoo to maintain the groundwater table of the region. These ponds, in turn, have helped to resolve the water crisis for the zoo animals.
“There was a path around the lake which allowed visitors to take a walk, especially when the migratory birds were here. Cyclone Vardah completely wrecked the walking trail. We have reconstructed the path and are now welcoming visitors to soak in the essence of nature,” informs Ramen.
“We have also created an excess water diversion channel, in case there is ever a chance of overflowing during heavy rains,” she adds.
Setting an example
December has just started and Otteri Lake is already witnessing the benefits of restoration. “Nearly 300 migratory birds have already nested around the revived lake, and it’s just the start of the season. We are hoping to see more of our ‘foreigner’ guests flying in soon!” smiles Sudha Ramen.
Her team has also installed several birdhouses atop the surrounding trees which are now abuzz with chirping sparrows and local birds. Alongside, lots of butterflies are also being sighted in and around the lake of late.
The revival of a lake as large as Otteri in less than a year proves what a little determination and zeal can achieve. The leader of this extraordinary project, officer Sudha Ramen, wants such efforts to be replicated systematically across the country so that thousands of dying lakes, rivers and water bodies across India can be restored to their former glory.
(Edited by Saiqua Sultan)