Case study on the performance assessment of addis ababa city road network

Abstract

The study is carried out for Addis Ababa city, which is the capital city of Ethiopia, with population over 3.0 million. It is situated on mountainous landscape at an allitted of about 2,500 meters above mean sea level and extends over 500km2 .The road network of Addis Ababa is limited in extent and right of way. Its capacity is low, on-street parking is prevalent, and the pavement condition is deteriorating. Despite a large volume of pedestrians, there are no walkways over a large length (63%) of the roadway network. This is a major concern because it contributes to the increased pedestrian involvement in traffic accidents (10,189 accidents occurred in 2004). The main objective of this project is to evaluate/assess the performance of road network in Addis Ababa. The scope of the project is to evaluate case study on the performance assessment of Addis Ababa city road network. The use of secondary source (literatures, books) as a source of information and data collection direct from case study area. The trend in change of road density from 1997 E.C up to 2005 E.C. is increasing significantly on average annual growth of 8.9%. So this result means the ratio of the area covered with road in the city is increasing which in other words enhancing mobility and accessibility in the city. The trend in road performance is constant in some years like from 1997 E.C. to 2000 E.C. and then gradually increases starting from 2000 E.C. So based on the evaluation indicator of road performance, increasing the total length of paved roads will increase road performance then the road network performance will be good. The road serviceability in the city is increasing gradually from 1999E.C. up to 2005 E.C. but the rate in change is very low which means the construction of new roads is not much reachable by the peoples and to increase the accessibility/serviceability of roads in the city we have to work hard in developing good road network in which it increases peoples benefit and development of the city. The percentage of accidents occurred in straight and flat slope part of the road from the network is around 90.05% [(38397/42640)*100] this shows that even we construct a comfortable road for the drivers it may reduce the performance of the road when we evaluate according to safety. Also when we see the percentage of accidents occurred in the road with good asphalt condition is 96.3% [(41060/42640)*100] which is even higher the former. This shows that connecting the city with new asphalt roads may reduce the performance of the road in respect of safety. All sub-cites will have greater than one beta index which shows a better connectivity in the sub city. The overall results of traffic distribution show those peripheral areas of the cities prohibited from enjoying an acceptable level of connectivity. these areas have low density of road network and, as expected this city are physically close to each other, peoples still have to travel longer distances to their destination.