Evaluation of Erosion Effects on Some Roads in Yenagoa City of Bayelsa State, Nigeria

This research evaluates the effects of erosion some roads in Yenagoa city of Bayelsa State. Reconnaissance survey was carried out to assist in the identification and accurate delimitation of the study area. Factors responsible for erosion in the study area were observed to ranges from natural cause including topography, rainfall and soil nature. Human factor responsible for erosion in the area studied include land use pattern and waste disposal method, poor construction and maintenance activity. Effect of erosion on the studied area includes Rendering of road way non motor able through creation of gullies, Carving in (slope instability) on drains ditches that were not lined, Flooding of road ways during rain due to blockage of drains, Pollution of water bodies in the environment as a result of sediment deposition, Destruction of Pavement infrastructure i. e. pavement, culverts and drainages. It is therefore concludes that Erosion also have various effects on street roads not all factors assumed to be responsible for erosion form agricultural perspective is responsible for erosion on street roads. However, with good management practices, and paving of roads, the problems of erosion in built up area can be controlled. This research focussed on the production of street roads map that guide the assessment and evaluation of impact of erosion in some part of Yenagoa metropolis Bayelsa state. Digital surveying method was adopted through the use already existing map of the city and field data obtain from GPS survey. Some features were coordinated using GPS for updating the new features that does not exist on the old map. Important features such as roads, etc were obtained from the existing map. Ground truthing and field editing were also carried out. All the processing was carried out using AutoCAD 2010 and ArcGIS software.