Quantitative Risk Assessment in Road Construction Project Management in Anambra State

This study applies quantitative risk assessment methodologies to road construction project management in Anambra State, South East Nigeria, where high rates of project abandonment, cost overruns, and schedule slippage have characterised public road construction programmes over the past decade. Quantitative risk management integrates probability theory, statistical modelling, and decision analysis to move project risk management beyond qualitative risk registers towards mathematically defensible risk quantification that can inform procurement decisions, contingency provisioning, and contract structuring. The study draws on project cost and schedule data from twelve completed and ongoing federal and state road contracts in Anambra, covering the period 2018 to 2024. Monte Carlo simulation is applied to model the joint probability distribution of project completion cost and duration, using triangular and PERT distributions to characterise uncertainty in individual cost and duration components. Sensitivity analysis identifies the risk factors contributing most to cost and schedule variance, including subcontractor performance, material price fluctuations, and design change frequency. The probability of project completion within budget and on schedule is computed under baseline and risk-mitigated scenarios. Results indicate that unit cost uncertainty in asphalt surfacing works is the dominant driver of overall project cost risk, accounting for 34 percent of total cost variance across the sample. The study recommends the adoption of Monte Carlo-based contingency estimation in the Anambra State Ministry of Works procurement guidelines. Keywords: quantitative risk assessment, Monte Carlo simulation, road construction, project management, Anambra State