THIRUVANANTHAPURAM: Construction of the port at Vizhinjam was not the reason for the increased erosion seen along Thiruvanathapuram coast, the National Institute of Ocean Technology (NIOT) has said. “Climatic events led to the erosion. The construction had little impact,” said a white paper released by the Chennai-based institute that was appointed by the Vizhinjam International Seaport Limited (VISL) for the study.
It said erosion hotspots such as Shankhumukham and Valiyathura were beyond the impact area of the port. However, scientists who have studied the erosion found the report limited in scope and said the construction did have an impact.
The paper said the erosion at Valiyathura and its northern stretches could be due to the presence of the groyne field to the south (Poonthura to Beemapally). It said the erosion will be rectified with sediment bypassing from the south. But scientists said the bypassing was affected due to the construction.
Impact will be felt in next 5 to 10 years: scientist
“Coastal erosion started in the 1970s in the Panathura- Poonthura area. However, interruption in sediment movement due to the construction has left the northern coast highly vulnerable. The coast is a continuum. So, the disruption has a cumulative effect. The disruption in sediment movement has started impacting more areas in the north.
The impact will be felt in the next 5-10 years,” said K V Thomas, ex-scientist and group head at National Centre for Earth Science Studies. “There is an immediate need for a detailed sediment budget study taking into account the south and north sediment movements,” he said, adding that the NIOT report was silent on sediment transportation affecting coastal continuum.
Though he agreed with NIOT’s findings that untimely climatic events such as cyclone Ockhi and Tauktae could disrupt sediment transport, Thomas said the impact won’t last for long when compared to the disruption of sediment movement by a hard structure. A J Vijayan, founder secretary of National Fishworkers Forum who had moved the National Green Tribunal, alleged that the white paper did not address basic issues.
“When cyclones hit, the stable beaches withstood their impact but the vulnerable coast suffered. Human interventions like the port construction have made the coast more vulnerable,” he said. “Last year, there was no erosion. No loss of houses was reported. This doesn’t mean the situation will remain the same in the coming years,” said Vijayan.
The white paper said no conclusion was made that the north of the port is eroding or south of the port is accreting at this peculiar location. Erosion spots exist in the south and accreting spots are in the north, but there is no mention about the latter. The white paper is based on the latest report submitted to the expert committee of the National Green Tribunal and comes at a time when a government-appointed expert committee is set to begin its study on the impact of the port on the coast.