Comparative analysis of sewer physical condition grading protocols for the City of Edmonton

Abstract

Condition assessment is a key component of successful asset management, and many diverse condition assessment protocols exist for sewer mains. These protocols are used to generate condition grades for sewer mains after inspection. Condition assessment protocols are important because renewal actions for sewers are prioritized based on condition grades. If condition grades assigned to sewers do not reflect actual pipe conditions close enough, the resulting allocation of resources will not be the best. This paper presents a comparison of three possible sewer condition assessment protocols for the City of Edmonton: the Pipeline Assessment and Certification Program quick grading method, the Manual of Sewer Condition Classification fourth edition, and the City of Edmonton’s Sewer Physical Condition Classification Manual. The results show that structural sewer condition grades depend significantly on the protocol used; therefore, protocol selection has significant financial consequences for asset management programs in the city.