Geospatial mapping for optimizing Right-Of-Way (ROW) acquisition in gas pipeline construction

This study aims at mapping of the Right-of-Way (ROW) acquired from KP292 Escravous at Mojoda, Epe, Epe Local Government Area (LGA) to Lekki Free Trade Zone Area, Ibeju-Lekki LGA, both in Lagos State, Nigeria, for the construction of gas pipeline networks. The total distance covered is 52.6 km of which 5.6 km is presented for this study. The methodological tools used are Remote Sensing, Geographical Information System (GIS) and spatial analysis techniques for the assessment of the terrain, land use, and environmental constraints along a pipeline corridor, identifying suitable routes and Multi-Criteria Decision Analysis (MCDA) and Least-Cost Path Analysis (LCPA) to determine the most efficient pipeline alignment. This study provides geospatial data (coordinates and elevations i.e. X, Y, Z) of locations and features (artificial and natural) within the ROW; the planimetry and longitudinal profile of the route for the purpose of designing and planning for the construction of the proposed gas pipeline route. The height of the centre line at the starting point 0+000 of the project at Mojoda is 48.120 m. The highest point on the centre line ground level for the entire route is 49.100 m at 0+100 chainage; and the lowest height of 2.400 m is recorded at 5+600 chainage. The accuracy of the traverse and levelling is 1/36,000 and + 0.011 respectively. The results obtained show the amount of cut and fill that is required by the Engineer in the process of construction and laying of the gas pipelines; and the cost implications for the construction of the project including compensation. Therefore, it can be concluded that geospatial data is the bedrock for the acquisition of ROW for the construction of gas pipeline.