A New Standardized Inspection System for Periodic Visual Surveys of Water Storage Tanks and Pumping Stations

The efficient planning of operation and maintenance (O&M) interventions and short-term investments requires adequate and tailored inspection protocols of existing infrastructures. The current study proposes a new standardized inspection system for periodic visual surveys of storage tanks and pumping stations of urban water infrastructures. The proposed system aims at identifying and classifying anomalies in terms of severity, intensity, and extension to evaluate the asset and its components deterioration. Inspection forms specific for water storage tanks and pumping stations are proposed. A set of 22 water storage tanks and 17 wastewater pumping stations located in Portugal were inspected using the developed system. Several anomalies' interdependences have been identified based on advanced statistical analysis and correlation matrices. Results have also demonstrated that good O&M practices caused slow asset deterioration and increased the asset service life. Main lessons learned concerning the most frequent anomalies, the most frequent distressed components, and the influence of O&M practices in asset deterioration are summarized, allowing a more efficient management of urban water infrastructures. Future research should focus on a wider inspection survey to assess the effectiveness, comprehensiveness, and reliability of this standardized system and to extend it to other urban water assets (e.g., pipes and treatment facilities).