Investigating the Long-Term Performance of Build-Operate-Transfer Projects in Nigerian Infrastructure: A Cost and Value Analysis

Build-operate-transfer (BOT) projects represent a significant mechanism for mobilising private finance for infrastructure in Nigeria, yet their long-term cost and value performance has not been rigorously evaluated beyond the construction phase. This study investigates the long-term performance of BOT infrastructure projects in Nigeria from a cost and value perspective, covering projects across road, port, power, and water subsectors in Lagos, Abuja, and South South zones. A longitudinal mixed-method design was employed, with financial performance analysis of 14 BOT projects over operational periods of 5 to 15 years, supplemented by 55 expert interviews with concessionaires, regulators, lenders, and user representatives. Life cycle cost analysis, financial ratio analysis, and thematic coding were applied. Findings reveal that 9 of 14 projects have underperformed revenue projections by 25% or more, driven by demand overestimation, tariff renegotiation, and governance failures. Cost performance during construction is better than under traditional procurement, but operational cost management deteriorates after concession year five in most cases. The study identifies a systematic absence of quantity surveying involvement in operational performance monitoring as a critical governance gap. A Long-Term BOT Performance Framework integrating cost management checkpoints at defined operational milestones is developed. This study makes an original longitudinal contribution to PPP performance research in sub-Saharan Africa. Keywords: BOT projects, long-term performance, Nigeria, life cycle cost, infrastructure