Assessment of Road Construction Related Social Costs and their Impact: A Case Study of Three Road Projects in Addis Ababa City.

Abstract

Construction project is helpful once completed; the phases leading up to completion can create a lot of inconveniences on the day to day activities of the community along the construction site. These inconveniences are called social costs, expenditures incurred by just third parties that are not contractually participating in a project. Social costs and their impact are not considered during estimation process of the project initial cost. Hence broader accountability should be taken by the parties involved within the project. This research explored the different types of road construction related social costs and their impact, the effect of road construction on traffic flow, to estimate the economic cost of traffic congestions and investigates the barriers why social costs are not considered during design and planning phase. The study used traffic count and travel time measurement to evaluate the effect of road construction on traffic flow and to estimate its economic cost, traffic count was conducted for five days (Monday through Friday), beginning at 7:00 a.m. and ending at 7:00 p.m. at 15-minute intervals and travel time measurement for predetermined segment length were conducted using the Average-Speed Technique with eight measurements taken for 30 minute. The survey approach with a set of questionnaires addressed to road users and consultants to evaluate the impact of social costs and to explore the understanding and level of consideration of social cost by construction professionals during design and planning phase. Traffic volume survey and travel time measurement during construction were analyzed and compared with the values before the beginning of the construction. Accordingly, during the construction phase the flow rate and maximum hourly volume has decreased due to the increased congestion. The travel time measurement portrayed that, travel time of vehicles and delay time has increased significantly with a reduction of travel speed of vehicles. Passengers delay cost, commercial vehicles delay cost, fuels wasted by passenger cars and trucks and commercial cost due to delay of commodities are the economic costs incurred and with annual monetary value 113, 559,587.22 birr/segment length for the three projects. The research has identified traffic congestion, slowdown of business activities, environmental pollution and disturbance of ecological and health systems as social costs. To evaluate the impact of these social costs to community the questionnaires from the respondents were analyzed & summarized below. Due to traffic congestion delay has occurred and impacts the road users by, loss of productivity, reduced working hours due to time lost on the way, loss of jobs to employers due to frequent lateness to work limited access to workers by employers. In addition traffic disruption also causes increase fuel consumption of vehicles due to burning fuel at a higher rate than smooth highway travel, property breakdown, frequent occurrence of accidents, lack of access entrance to their residence and lack of parking space are also the impacts confirmed by the respondents. Air pollution from the dust and carbon dioxide, potable water pollution and noise pollution has negative impacts to the community by polluting the environment. Displacement of peoples, health problem and reduction in quality of life are the impacts from the disturbance of the ecological system are also the impacts confirmed by the respondents. Social costs are often not incorporated into construction design and planning. This can be attributed to difficulty in distributing social costs, interferences from clients, lack of historical data, underestimation of social costs and low stakeholder attention to social costs. This is confirmed by 87.23% of the survey conducted to grade one consultants who participate in design and tender documents preparation. To alleviate social costs and their impact during construction it is recommended that, scheduling works for off-peak hours and coordinating work for effective resource utilization, incorporate social costs into tenders, use a good traffic management system, avoid full or partial closures of roads by designating temporary roads, changing the hours or days when work is done, avoid project delays, control dust emission by proper and continuous showering.