Route Location by Gis Analysis: Case Study of the Proposed Lukenya-kilimambogo Greater Eastern Bypass

Abstract

Much traffic has been witnessed on city roads, thus prompting the authorities to come up with alternative route to ease the problem. In order to accrue benefits on cutting down on the lost manpower hours and movement of goods, there is a need for an optimal bypass to accommodate traffic from Mombasa on transit to Central, Eastern and North-Eastern counties without passing through Nairobi CBD. Routing is a very important aspect of highway planning and design, hence a distribution system that strikes a balance between environment, engineering, technological, as well as social factors is vital. This research uses GIS (Geographic Information System) analysis and geospatial modeling to develop an ideal Great Eastern by-pass route, using Lukenya junction and Kilimambogo on A3 as start and end nodes. To find the best route, a model is created that takes into account highway lengths, topography, soils, populated regions, game parks, forests, rivers, swamps, roads, open water sources sites, and protected areas. For spatial modeling, analysis, and data overlay, GIS is used to assess their comparative preferences, the factors are weighted according to their importance. Environmental elements have the highest level of preference in the weighting output, social and engineering considerations are next in line, and receive the lowest preference. The best path is determined by weighting, and the engineers' proposed route is evaluated for suitability. By minimizing high-cost environmental and congested areas, money is saved by taking the optimal route. As an early attempt for highway routing, the findings of this study will reveal the benefits of combining diverse data sources with GIS analysis. This can be used in Kenya to route other linear projects.