Risk Assessment and Mitigation in Bridge Construction Projects in North Central Nigeria

Bridge construction projects in North Central Nigeria, including those crossing the Niger, Benue, and Kaduna Rivers, involve complex technical, environmental, and procurement risks that require systematic professional risk management. This study conducts a professional risk assessment and develops a mitigation framework for bridge construction projects in the North Central geopolitical zone. Primary data were collected through structured questionnaires administered to 50 engineers, project managers, and contractors with direct experience on bridge construction projects in Plateau, Niger, Benue, Kogi, and Kwara States. Risk probability and impact were assessed using a 5x5 risk matrix for 30 identified risk categories. Risk register analysis and severity ranking were performed. Results indicate that the five highest-priority risks are: contractor default due to cash flow failures, foundation conditions significantly worse than site investigation predictions, flood events during construction season, material supply chain disruptions, and community interference near project sites. Foundation risk is most severe in riverine projects crossing alluvial channels with variable depths to bedrock. Contractor financial default is identified as affecting 45 percent of surveyed projects to a significant degree. The study develops a North Central Nigeria Bridge Construction Risk Register with project phase-specific mitigation measures, recommending its adoption as a standard tool in pre-contract project planning by federal and state highway agencies operating in the zone.

Keywords: risk assessment, bridge construction, project management, North Central Nigeria, risk mitigation