The management and sustainability of engineering structures represent a critical challenge for road networks in West Africa, where early degradation of these structures generates considerable maintenance costs and safety risks. This study statistically analyzes a database of 1,055 engineering structures inspected across all 14 regions of Senegal, using the French IQOA (Image Qualité des Ouvrages d’Art) assessment framework. The aim is to establish the relationship between construction deficiencies (insufficient cover, concrete surface defects, incomplete drainage systems, honeycombing) and accelerated structural degradation. Results show that 33% of structures are in satisfactory condition (class 1), 46% exhibit minor disorders (class 2), 9% require specialized maintenance (class 2E), and 11% are in structurally concerning condition (classes 3 and 3U). The analysis reveals that construction-related deficiencies — particularly insufficient reinforcement cover and waterproofing defects — are significantly associated with the most severe degradation classes, especially in coastal saline environments. These findings provide unprecedented empirical evidence for improving construction practices and maintenance strategies in West Africa.