Bathymetric study underway in Pallikaranai marsh to improve ecological functions

Bathymetric study in Pallikaranai marsh to enhance water capacity and ecological functions, addressing degradation and flood issues.

In a first, a bathymetric study is under way in and around Pallikaranai marshland to assess the volume of sludge that can be dredged to enhance the marsh’s water holding capacity and ecological functions.

Bathymetry, which involves measuring underwater topography, is essential for developing comprehensive maps that can aid in determining the water storage capacity and flood patterns. It plays a critical role in wetland design, restoration, land use planning, and legal boundary determinations.

Pallikaranai marsh, which received the Ramsar tag in 2022, continues to face significant anthropogenic pressures, including encroachments and sewage discharge. Deepak Srivastava, Member Secretary of the Tamil Nadu State Wetland Authority, emphasised the study’s importance in addressing the degradation of the marshland.

To ensure scientific rigour, the Authority has collaborated with the National Centre for Coastal Research (NCCR) to investigate multiple locations within the marshland, he said. The study has so far been carried out in five places, including Elcot, Okkiyam Maduvu, Buckingham Canal, Thangavelu Engineering College, and Pallikaranai marshland.

M.V. Ramana Murthy, NCCR Director, explained that the study addresses two critical issues — wetland degradation and inadequate flood water drainage. By analysing entry and exit points, the study aims to restore natural inlets and outlets, identifying bottlenecks to maintain optimal water levels. The dredged sludge will be carefully assessed and disposed of in suitable locations, Mr. Murthy said. 

Incidentally, the study is being conducted amidst the National Green Tribunal’s insistence on clearly defining the boundaries of the marshland to prevent further encroachments.