This study assesses the impact of Water, Sanitation, and Hygiene (WASH) infrastructure projects implemented under the Multi-Sectoral Crisis Recovery Project (MCRP) in Adamawa State, North-East Nigeria. In response to the protracted crisis caused by the Boko Haram insurgency and environmental challenges, the MCRP was launched by the Government of Nigeria in collaboration with the World Bank to restore essential services, improve livelihoods, and rebuild social cohesion. Specifically, the WASH infrastructure of the MCRP aimed to rehabilitate damaged infrastructure, improve access to clean water and sanitation facilities, and promote hygiene awareness in affected communities. Using a mixed-methods approach, the study evaluates the state of WASH services before and after the intervention, measuring changes in infrastructure access, health outcomes, and community behavior. Findings indicate a significant improvement in access to safe water sources (from 18% to 73%) and a sharp decline in open defecation (from 34.4% to 3.9%). Additionally, increased community participation and the perceived inclusiveness of the intervention contributed to enhanced social cohesion. However, the study also identifies lingering gaps in stakeholder engagement, sustainability structures, and community awareness of maintenance mechanisms. The study concludes that the MCRP WASH intervention has contributed meaningfully to public health, social stability, and resilience in Adamawa State. It recommends strengthening community engagement, institutionalizing maintenance structures, and aligning future interventions with local development policies to ensure the long-term sustainability of WASH services. The research provides critical insights for policymakers, development agencies, and practitioners aiming to implement recovery-focused infrastructure interventions in fragile and crisis-affected settings.