Flood Risk Monitoring Around Part of the Niger Delta Basin of Nigeria

The influence of environmental geohazard events on the society are numerous and are seriously affected by the extent of flood which is exacerbated by climate change variables. This research is tailored towards investigating the dynamics of frequently occurring natural flood disaster. The recently launched Sentinel-1 SAR satellite constellation were adopted for temporal feature extraction and extent assessments over the study area. Methodology adopted involves Binarization (Thresholding) techniques, suitable pixel intensity through Band Maths to calculate and extract water accumulation with-in the Area of Interest (AOI). Result obtained shows that, number of scenes has no influenced on the expected outcome with a gradual increase in flood geohazard from September 2017 (10.49345%) to May 2018 (12.6057%) and a slight drop in May 2019 (11.47714%). Flood events persist a gradual progressive increase over time with that of October 2022 as high as (12.29319%). It was observed that May, -2018 have the highest percentage of water shade area (12.6057%) with the highest percentage of flood geo-hazard, then October, 2020 (12.29319%), then May, 2019 (11.47714%) and September, 2017 (10.49345%). Rate of water accumulation over the AOI was predicted with an extension to October, 2022. It was evident that flood event is a gradually accumulated and continuous geo-hazard event. Being a continuous phenomenon, over a period of time, it however consumes the solid part of the earth surface made for human activity such as farming and dwelling places. It could be seen that flood rate is not constant because other drivers could also contribute immensely towards increasing flood geohazard. The findings suggest a continuous monitoring so as to have a more reliable and current information on geo-hazard phenomenon.