State's coastline depleting: Study

 “Unprecedented developmental activities” and “rising sea levels” have had a marked impact on the shoreline / coastline of Karnataka, which has been slowly, but steadily depleting.

The study conducted by the National Centre for Sustainable Coastal Management (NCSCM), Ministry of Environment and Forests (MoEF), shows that 34 per cent of the coast of Karnataka is eroding from 1972 - 2010. The assessment also indicates that 27 per cent of the State’s coast is accreting. Of the 320-odd km stretch, only 14.5 per cent of the coast is stable, where neither accretion nor erosion has occurred over the past 38 years, reveals the satellite data analysis.

Nearly 25 per cent of the State’s coast is rocky, and about 15 per cent of coastline has been categorized as artificial coast due to the presence of seawalls. It was observed that ‘medium’ and ‘low’ erosion was dominant along 18.6 per cent of the coast. The erosion was observed equally at both North and South of creek or river mouths along the State’s coastline.

NCSCM, which started mapping the entire country’s shoreline to ascertain the nature of erosion in all the coastal states a year ago, recently completed the exercise. Shorelines of Gujarat, Maharashtra, Goa, Karnataka, Tamil Nadu, Puducherry, Andhra Pradesh, Orissa, West Bengal, were analysed in the last few months. Ramesh Ramachandran, Director, NCSCM, Chennai, told Deccan Herald that while  Gujarat, Kerala, Tamil Nadu, Puducherry, Orissa governments had approved the findings of the Center, Karnataka was yet to give its nod.

“Karnataka is yet to approve the maps. The Karnataka government is in the process of verifying the findings with its own departments including, ports, PWD and fisheries. The government may or may not entirely accept the findings. In such an event, we will have to incorporate changes and submit the final report to the MoEF,” he said.

He said that the assessment on the Karnataka coast, representing long-term shoreline change evaluation for a period of 38 years (1972-2010), was based on comparing four historical shorelines extracted from satellite imageries for the said period, with shoreline derived from LISS IV images. The historical shorelines represent the following periods: 1972 (Survey of India Toposheet) used as a base map; satellite imageries of 1972, 1990, 2000 and 2010.

Ramachandran said that with the first phase of studying the ‘erosion line’ completed, the Center was in the process of furthering the mapping by using High Resolution Satellite Imagery along with DEM to derive precise shoreline changes.

“In the second phase, images are being procured from the National Remote Sensing Agency. The use of High Resolution satellite imageries will help ascertain the overall erosion status more accurately,” he said, and added that the project cost was Rs 150 crore.