BHUBANESWAR: Construction of hard structures along the coast near Gopalpur has led to massive erosion, endangering Olive Ridley turtles and the nesting ground Rishikulya during the last one decade, finds a recent global study.
The study conducted by 11 researchers from six universities, including two from Brazil, revealed almost the entire Gopalpur shoreline experienced erosion between 2010 and 2020 and the construction of Gopalpur port markedly impacted the shoreline dynamics.
From south to north, the 12.3 km long Gopalpur coastal stretch was divided into four zones based on natural and human landmarks, such as river/estuarine inlets, breakwaters and jetty/groins to analyse the overall shoreline morpho-dynamics in response to the recent development of port and other related infrastructure.
The inter-annual trend of shoreline variation showed that Zone-1 remained practically stable throughout the study period. Even as Zone-2 was stable between 2010 and 2011, the port region showed a prominent deposition feature after the breakwater construction in 2012.
The results of the shoreline shift in Zone-3 showed that the region was also stable until 2011 but was chronically disturbed after the port construction and operational activities, increasing erosion and accretion cycles. The north side of the port (Zone-4) continues to experience severe erosion. At Zone-4, the first 2.5 km falls inside the groin field region dominated by strong erosion with higher magnitudes at the extreme north, found the study.
Professor of department of Geography at FM University Manoranjan Mishra said most ports on the east coast showed a similar pattern of erosion and deposition as observed in the study. The construction of breakwater perpendicular to the coastline prevented the uniform distribution of littoral sediments in all cases, he said.
Since the Odisha government is contemplating construction of 14 more ports, the researchers warned, the ports could potentially impact its fragile coastal system. They claimed, the resilience of the coastal landforms is compromised due to the construction of onshore and offshore coastal infrastructures in order to meet the growing demand for economic activities.
Previous studies had also observed a similar trend of erosion and accretion along the eastern coast. The northern part of Paradip port experiences intense erosion due to the construction of a rigid engineering structure (sea wall).
The southern part of Paradip port also had signs of erosion. Although accretion pattern was witnessed along Dhamra port from 1990 to 2000, drastic erosion was observed after the port area development in 2007.
The researchers said hard engineering structures like seawalls, breakwaters, groins, and ripraps built to prevent such erosion may further exacerbate negative consequences.
"The impact of man-made coastal infrastructures and climate changes are responsible for a huge amount of mangrove and fauna degradation and morphodynamics in coastal zones. Though Gopalpur port authorities have undertaken some steps, several other issues are yet to be addressed. Systematic observation and monitoring are necessary to lessen the resulting damage," Mishra added.
The study has been published in the recent issue of the international peer-reviewed scientific journal 'Science of the Total Environment'.