A distress-based condition assessment approach of urban water assets using novel deterioration indices

Abstract

This paper aims at proposing and demonstrating the application of a novel distress-based condition assessment approach to evaluate the physical condition of inspectable urban water assets based on the classification of anomalies in terms of severity, intensity and extension using three new deterioration indices. These indices are, firstly, calculated at the asset component level and, then, aggregated at the asset level and at the infrastructure level by weighing the component indices with the respective replacement cost or criticality. A condition grading classification associated with the deterioration indices is proposed. The novel distress-based condition assessment approach is applied to 22 drinking water storage tanks and 17 wastewater pumping stations located in Portugal, that have been specifically inspected for this purpose. Results of deterioration indices are compared with those obtained by the value-based condition assessment approach. Results demonstrate that the proposed approach allows a more reliable assessment of the assets’ condition and a more robust establishment of priority rehabilitation or maintenance interventions