Coastal erosion dynamics and landmass change along Cape Coast - Sekondi coastline in Ghana

Abstract

The purpose of the study was to investigate the extent to which coastal erosion, accretion and other processes, including human activities, have influenced changes in the coastline between Cape Coast and Sekondi in Ghana. The study sites were Cape Coast, Ekon, Komenda and Sekondi. Fifty pebbles each from the study sites were picked for the study. Sand particles were also sampled from the three study sites. In addition, satellite images, aerial photos as well as topographical maps and Global Positioning System (GPS) Survey were used for shoreline analysis and land cover/use change. Measurements ot abrasion platforms, raised beaches, high and low water marks were also manually taken. Forty-five respondents were also purposively selected for in-depth interviews and community interactions. The analyses were done on the basis of Caillieaux indices for pebble analysis, Wentworth Scheme of Grain Analysis for sand, Digital Shoreline Analysis System for shoreline change and digitization of aerial photographs and topographical maps for land cover change. Photographs were also taken and used as part of the analysis. It came out that erosion was more intense between Ekon through Cape Coast and Komenda than Sekondi. Generally, the current shorelines were found to be accreting and retreating. The dominant land cover is built up. The impact of sea erosion was both physical and human. It was therefore recommended that any preventive measures against dynamics of the sea such as erosion should consider both the natural and human dimensions. It is therefore imperative for continuous monitoring of the coast to keep abreast of the changes that will occur as a result of either erosion or accretion.