Abstract
The aim of this work was to develop a geographic information system (GIS) based road network map of Port Harcourt city that can be used to analyze traffic congestion within the city and suggest possible solutions. The handheld global positioning system (GPS) was used to acquire geographic coordinates of major locations experiencing traffic jams, bad spots and schools. The transformed GPS coordinates were added to the ArcGIS environment to define the spatial locations. Prior to that, the road map was digitized and geo-rectified. Satellite Imagery from the remote sensing technology was used to acquire data of new roads, for map updating and revision. Geographic information systems (GIS) operations (buffering, overlay and networking techniques) using ArcGIS 9.3 were performed on the road map. The study recommends that: the road network in Borikiri axis of Port Harcourt should be improved by constructing a by-pass to ease the traffic along Harold Wilson road; the width of roads should be increased at T-junctions and cross-junctions; all public facilities especially those located along major roads should have good parking plots before approval for construction. It is also recommended that at proximity of 500 km from a developing area, a boulevard should be constructed at the junction linking such area to the center of the town, for instance, the Wimpey/Iwofe junction. The road network as predicted in this study is expected to contain a minimum of 217,360 cars in 2022 for the identified routes excluding larger vehicles like trucks.
Key words: Road network, Geographic information systems (GIS), traffic congestion, Port Harcourt, global positioning system (GPS).
