NIOT introduces green tech to combat erosion

Speaking at SPREAD 2019 (Shore Protection and Remediation using Eco-friendly Alternative Designs), Dr Vijaya Ravichandran, scientist with NIOT, explained that climate change has led to an increase in the wind intensity of cyclones. “This has led to major shoreline erosion, affecting livelihoods, and property. The natural cause for shoreline erosion is waves, but human intervention does affect this process,” she said. Taking satellite images of the shoreline at Kadalur village near Kalpakkam, where her team were requested to implement eco-friendly and sustainable shore protection measures, she noted that over the course of ten years (from 2003 to 2013), the shoreline had eroded drastically.

“Initially, the only method we had was to construct a sea wall. However, this would cause scouring of the shoreline. We could also opt for yearly sand nourishment, which would not impact the surrounding areas, but availability and cost issues arose. Thus, we settled on a submerged breakwater,” said Dr Ravichandran. Breakwaters are structures that stop coastline erosion by blocking stronger currents and allows surface waves to pass by. They would constitute of geotextiles, or permeable fabrics, and be able to provide an eco-friendly and easily implementable method to protect the coastline. “When we visited the site, we found that mollusks and mussels had gathered on the breakwater in large numbers. This, in turn, attracted many fish, and this led to more birds in the area. We used locally available material and filled the geotextile with sand. The benefit is that if the structure needs to be removed, it is easy to collapse,” said AS Kiran, a scientist.