Odisha’s 1st geo-tube seawall project in Kendrapara
Kendrapara: Odisha’s first geo-tube sea wall project under World Bank-funded Integrated Coastal Zone Management Programme is likely to get underway in Kendrapara district shortly.
IIT-Chennai has accorded the ‘go ahead’ to the much-awaited sea-erosion-control project after its experts conducted wide-ranging scientific and morphological study of the vulnerable sea coast.
“It has submitted the report. The premier institute has also approved the technical design and plan of the anti-sea-erosion project at Pentha in Rajnagar tehsil. Tender bid of Rs 22 crore project is being invited. We hope work will start this winter,” Executive Engineer, saline embankment division, Jugal Kishore Tripathy said.
The sea wall where geo-tube barrier will be installed would come up at an estimated Rs 22 crore.
The embankment height would run up to 7.4 metre. The tidal surge rises up to 5 metre during cyclonic storm. Thus it could withstand the ingress of tidal waves. The length of the embankment would be 675 metre instead of 700 metre as it was earlier planned, he said.
IIT experts had conducted scientific study of the erosion-prone coast for installation of geo-tube sea wall to save a cluster of highly-threatened hamlets in the district.
Oceanographic experts deputed by IIT-Chennai had studied, among other things the beach profile, moisture content of sand particles, morphology of the eroded beach, intensity, frequency and velocity of waves, Tripathy said.
Of the 480-km long coastline in the state, 39.3 km is undergoing various degrees of sea erosion. The Pentha coast set for geo-synthetic tube refurbishment comes under high erosion zone, officials said.
The Executive Engineer said, “Environment and forest ministry on the basis of onscreen digitisation of coastline and satellite imagery study has found that over one-third of the state shoreline is exposed to varying degrees of sea erosion. Of it, 8.2 per cent is severely hit by sea erosion. That includes Pentha coast.”
“Till the project gets underway, temporary measures like putting up timber stumps, bamboo poles and sand-filled bags have been put in place to tame the advancing sea. However, measures like this in the past had badly failed to arrest the rampaging sea,” Tripathy said.
As per technical plan, geo-tubes made up of high grade rexin and filled with sand would be put in place at the erosion-hit Pentha embankment in the Rajnagar ‘tehsil’.
The sand-filled bags would act as protective barrier against tidal waves. It would absorb the tidal ingress, salinity contents and sodium chloride contents in sea water and would stop the erosion of embankment, according to technical experts in saline embankment division.
Several thickly populated human settlements including the coastal Rajnagar block headquarters are presently exposed thoroughly to sea erosion.
Experts are of the view that use of geo-tube would be a better erosion-proof mechanism, as it would reduce striking force of the mighty sea waves. Stonewalls and breakwater systems usually cave in by being battered by waves, but the geo-tubes could sustain such shocks.
Besides, it has been found that the sea wall or the breakwater system often diverts the erosion trend to other vulnerable shoreline.