{ "background": "Municipal infrastructure asset management systems (AMS) are promoted as essential for risk reduction in low-resource settings, yet robust empirical evidence of their effectiveness in sub-Saharan Africa is scarce. Existing evaluations often lack methodological rigour, relying on descriptive case studies.", "purpose and objectives": "This study aimed to provide a quasi-experimental evaluation of the causal impact of formalised AMS implementation on technical risk metrics for municipal water and road infrastructure.", "methodology": "A difference-in-differences design was employed, comparing 12 intervention municipalities that implemented a standardised AMS framework against 12 matched control municipalities that did not. Infrastructure risk scores, derived from condition, criticality, and capacity indices, were measured at two time points. The core impact was estimated using the model $Risk{it} = \\beta0 + \\beta1 (Treati \\times Postt) + \\gamma X{it} + \\epsilon_{it}$, with municipality and time fixed effects. Robust standard errors were clustered at the municipal level.", "findings": "The implementation of a formal AMS was associated with a statistically significant 18.2% reduction in aggregate infrastructure risk scores (95% CI: 12.7% to 23.5%). The effect was more pronounced for water assets than for road networks. Sensitivity analysis confirmed the robustness of this finding to potential unobserved confounders.", "conclusion": "The quasi-experimental evidence confirms that structured asset management systems can materially reduce technical risk for municipal infrastructure in a sub-Saharan context, validating their strategic importance for engineering practice.", "recommendations": "Municipal authorities should prioritise the adoption and institutionalisation of formal AMS frameworks. National policy should support this through guideline development, capacity building, and dedicated budget lines for asset data collection and system maintenance.", "key words": "asset management, infrastructure risk, quasi-experimental, difference-in-differences, municipal engineering, sub-Saharan Africa", "contribution statement": "This paper