Using Intelligent Desktop Assessment Methods to Match Advanced Condition Assessment Tools to Sewer Interceptor Network Vulnerabilities

Abstract

Sewer Interceptor networks are typically comprised of large diameter critical pipes. In mature cities, the networks span pipes from centuries old brick, cast-in-place and precast concrete, clay tile to more modern materials including both thermoplastics and thermosetting composites. Older vintage pipes also often include segmental concrete and clay tile pipes. In the last two decades, advancements in inspection platforms have expanded considerably to include multi-sensor instrumental setups with a wide array of equipment (e.g. HD CCTV, LiDAR, SONAR, H2S Sensors, pipe penetrating radar, etc.) coupled with an equally wide array of traditional and expanding methods of material sampling and testing techniques. Very little has been published on matching the modern array of assessment techniques for critical gravity pipes based on specific era or exposure vulnerability and the condition assessment method(s) that are best matched to the vulnerability. This paper presents an overview of the evolution of design and manufacture of the most common materials interceptor networks and the intelligent use of desktop study techniques to best match the assessment method the materials. This is directly analogous to the recommended process for structuring condition assessment programs for large diameter pressure pipes and utilizes case studies from both the US and Canada to illustrate the process and its implementation.