The use of GIS in high voltage transmission line routing in Kenya: A case study of 132 KvKilimambogo-Thika-Kiganjo Line

Abstract

Energy is an essential input in the productive process of an economy. The Kenya Vision 2030 aims at transforming Kenya into a newly industrialized, middle-income country by 2030.Consequently Kenya Electricity Transmission Company (KETRACO) built a 43.6 km transmission line linking Kilimambogo, Thika and Kiganjo townships. Transmission line routingin Kenya has lately proved challenging due to growth in population and an increase in social and environmental awareness. In this study a model route was developed incorporating transmission line length, topography, geology, soils and land use to identify a least-cost pathway. First, factors affecting the routing process were identified, followed by weighting of the various factors to get the relative importance of each and finally Geospatial Information System (GIS) analysis used for spatial modeling and overlay to generate the route with the least technical, social and environmental resistance. This was compared with the existing line determinedby traditionalapproach. The existing path is 43.6 km long and the least cost pathway is 41.4 km. The results of this study demonstrate the benefits of integrating data within a GIS environment which acted as a spatial decision support system for transmission line routing.