Why Most Infrastructure Projects in Nigeria Run Over Budget

Nigeria's infrastructure gap is among the largest in sub-Saharan Africa. The African Development Bank estimated the continent's annual infrastructure financing shortfall at $68–108 billion, with Nigeria accounting for a disproportionate share. Into this gap flows substantial government capital and international development finance — much of which fails to deliver the intended assets on time or within budget.

The Auditor-General's reports, the Budget Monitoring and Price Intelligence Unit findings, and the testimonies of countless procurement officers paint a consistent picture: infrastructure projects in Nigeria routinely exceed their original cost estimates by 30 to 200 percent, and frequently take two to three times their planned duration to complete. This is not a new problem. But it is one that the sector has proven remarkably resistant to solving.

Beyond the Corruption Narrative

The reflexive explanation for infrastructure project failure in Nigeria is corruption — and it would be dishonest to suggest that corrupt practices play no role. They do. But corruption alone is an insufficient explanation, and over-reliance on it as a diagnosis obscures the systemic, technical, and institutional failures that drive cost and schedule overruns even in projects where procurement integrity is not in question.

In our project management advisory work, we have found that the majority of cost and schedule overruns have identifiable technical and managerial root causes that could have been anticipated, managed, and in many cases prevented. Understanding these causes is the prerequisite for meaningful improvement.

The Root Causes That Actually Drive Overruns

• ◆Inadequate scoping and front-end planning. The single most reliable predictor of project overrun is the quality of work done before the first contract is signed. Projects that proceed to procurement before completing rigorous feasibility studies, geotechnical investigations, environmental impact assessments, and detailed design consistently encounter surprises during execution that generate variation orders and claims. The political pressure to 'break ground' before this work is complete is intense — and the cost of yielding to it is enormous.
• ◆Unrealistic cost estimation. Nigerian infrastructure budgets are frequently based on rates that have not been updated for current market conditions, that do not adequately account for inflation over the project lifecycle, or that reflect optimism bias rather than historical performance data. When the gap between the budgeted amount and the actual cost of work is visible from the outset, the project is structurally set up for overrun.
• ◆Contractor capacity misalignment. Award of contracts to bidders whose financial, technical, and managerial capacity is insufficient for the work is endemic. The Public Procurement Act's emphasis on lowest evaluated bidder, without robust post-qualification assessment of execution capacity, consistently produces situations where contractors win work they cannot execute and then seek relief through claims, slow execution, and abandonment.
• ◆Weak owner-side project management. Government MDAs and many private clients do not maintain the qualified project management capacity needed to actively oversee complex infrastructure delivery. Site supervision is underfunded, resident engineers are inadequately resourced, and contract administration — the day-to-day management of the contractor relationship — is frequently poorly handled. The contractor that encounters weak supervision will, rationally, prioritise its own interests.
• ◆Inflation and macroeconomic exposure. Nigeria's inflationary environment and the volatility of the naira create real project cost escalation risks that are underestimated at appraisal and inadequately managed through contract mechanisms. Fixed-price contracts over multi-year periods in an economy with double-digit inflation transfer risk to contractors in ways that either inflate bid prices or produce contractor financial distress mid-project.

What World-Class Project Delivery Looks Like

The interventions that demonstrably improve infrastructure project outcomes in similar developing country contexts are well established. They require sustained political will and institutional investment — but they are not mysterious.

• ◆Mandatory project readiness assessments before budget appropriation, ensuring that adequate design, land acquisition, and environmental clearance are complete before funds are released.
• ◆Independent technical review of cost estimates and schedules before contract award, using current market data and internationally recognised escalation models.
• ◆Strengthened pre-qualification requirements that include financial audits, equipment registers, and evidence of comparable completed works — with mandatory post-award review if red flags emerge.
• ◆Adequately resourced project management offices on the owner side, with qualified resident engineers, contract administrators, and a functioning change management protocol.
• ◆Dispute resolution mechanisms that function rapidly, reducing the incentive for claims escalation and enabling issues to be resolved while projects are still in execution.

The Capacity Gap at the Centre of Everything

Running through all of these root causes is a common thread: the shortage of project management professionals with the technical competence and institutional authority to plan, execute, and oversee complex infrastructure projects in the Nigerian environment.

Nigeria produces engineering graduates in significant numbers. What is scarcer is the applied project management capability — the ability to translate engineering knowledge into project plans, manage contracts, exercise sound commercial judgement, and navigate the institutional environment of Nigerian public infrastructure delivery. Building that capability, systematically and at scale, is the prerequisite for a functioning infrastructure sector. Without it, the tools, systems, and governance reforms will continue to underperform their potential.