Assessment of Shoreline Changes of Kaiama Stretch of the Nun River, Bayelsa State, Nigeria

Shoreline is the transition between land and water body and it is susceptible to changes due to various coastal processes such as waves, tides, currents, storm surges, accretion, erosion, and anthropogenic activities such as dredging, mining, and various coastal Engineering constructions. The shoreline of the Nun River in Kaiama Town in Kolokuma/Opokuma Local Government Area (LGA) is affected by the processes of erosion and accretion and this phenomenon has constituted various natural hazards such as the annual river bank erosion that has led to the destruction of natural and artificial resources and also commercial activities. This research work aimed at assessing the shoreline changes in Kaiama stretch of the Nun River in Kolokuma/Opokuma LGA, to facilitate this, Remote Sensing (RS) and Geospatial Information System (GIS) were integrated to address the aim of the study. The shoreline for 1979 – 2019 were defined for each of the remotely sensed imagery for the four epochs, an overlay map was generated for the four sets of imageries obtained and a shoreline change map was produced on a scale of 1:20,000. The results revealed that the rate of changes on the left and right side of the Nun river for the following epochs were 1989 – 1999; 7.306m & 8.371m, 1999 – 2009; 14.246m & 16.263m, 2009 – 2019; 10.089m & 9.384m, 2019 – 2023; 13.211m & 24.724m respectively. These values represents the average distance change between shoreline vertices giving insights into the coastal erosion and accretion dynamics, the study revealed that coastal erosion and accretion simultaneously impacts both sides (left and right) of the Nun River.