In an effort to minimise salinity ingress in the city’s coastal areas, Environmentalist Foundation of India (EFI), a voluntary organisation, will take up work to restore more fresh waterbodies close to estuaries this year.
There are plans to revive nearly 11 waterbodies between Mamallapuram and Kadapakkam with the State government’s approval. The waterbodies to be restored include those in Vengampakkam near Kalpakkam, Kadalur Chinnakuppam, Paramankeni, Kodapattinam, Adayalacheri and Kadapakkam.
While the EFI has taken up a mix of projects from small ponds adjacent to the highway roads to large farm feeding lakes, the organisation has turned focus on the waterbodies near the estuaries as they are the final frontier of freshwater sources.
Many of these waterbodies have been left neglected without proper boundaries and affected with encroachments of lake area and used for farming. Kolapancheri or Arachi lake near the Muttukadu backwaters was one such waterbody restored with increased storage capacity by 35% recently.
Besides reducing salinity ingress and recharging groundwater, the restoration of such waterbodies like in Konneri near Mamallapuram, Allikulam in Akkarai and Ennore Thamaraikulam would help preserve characteristics of aquatic and marine habitats, said EFI volunteers.
EFI’s founder Arun Krishnamurthy said localised inundation had reduced for at least 1 km radius around the waterbodies that were rejuvenated during the monsoon last year. Several of them did not have proper inlets for floodwater to flow in.
For instance, agrarian encroachments for nearly nine acres had to be removed from Kollapanchery lake along Outer Ring Road, bunds were relaid and storage capacity enhanced by nearly 65%. These measures aided in conserving resources and reduced waterlogging.
Techniques like dual embankment and use of jute lining on the embankment and casuarina poles for fencing were executed to minimise impact of erosion, particularly in sandy soil areas, he said.
The EFI takes steps to plant native saplings and fence the outer circumference of the lakes to prevent encroachments. The work to revive lakes close to estuaries would be done between April and October.
