CONTRACTOR-RELATED VARIATIONS AND IMPLEMENTATION OF KENYA NATIONAL HIGHWAYS AUTHORITY PROJECTS
Keywords:
Contractor-related variations, implementation, Kenya National Highways Authority projectsAbstract
Contractor-related variations are a major source of inefficiency in road infrastructure projects, often resulting in delays, cost overruns, and disputes. This study investigated how contractor-related variations affect the implementation of Kenya National Highways Authority (KeNHA) road projects and examined the moderating effect of risk management on this relationship. Drawing on Agency Theory and Stakeholder Theory, the study adopted a descriptive research design involving 50 ongoing KeNHA road projects. The study identified a census target population of 600 respondents and obtained 443 valid responses, for a response rate of 73.8%. The study collected data using structured questionnaires and analyzed them using descriptive statistics, regression analysis, and moderation testing. The findings revealed that poor prioritization of work programs (M = 4.678, SD = 0.568), inaccurate estimation of project duration (M = 4.268, SD = 0.710), lack of specialized project managers (M = 4.084, SD = 0.807), and inadequate equipment mobilization (M = 4.045, SD = 0.738) were among the major contractor-related variations contributing to project delays and cost escalations. Regression results showed that contractor-related variations significantly affected project implementation and explained 61.2% of the variance in project implementation outcomes (R² = 0.612, F = 694.248, p < 0.001). Further analysis revealed that risk management significantly moderates the relationship between contractor-related variations and project implementation (β = 0.010, p < 0.001), indicating that effective risk management practices mitigate the adverse effects of contractor-related variations and enhance project implementation outcomes. The study concludes that contractor-related variations pose significant risks to the successful implementation of road infrastructure projects when not effectively managed. The study recommends strengthening risk management practices, enhancing contractor accountability, and improving project planning and resource mobilization to enhance project implementation outcomes in Kenya.
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Copyright (c) 2026 Francis Benedict Ondiek , Antony Sije, Yusuf Muchelule
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