ISTT Educational Webinar
ISTT Educational Webinar
Subject: Engineering-Based Condition Assessment of Large-Diameter Sewers and Wastewater Structures for Structural Capacity Evaluation
Category: Condition Assessment
Presenter: Dr.-Ing. Robert Stein Stein & Partner GmBH, Germany
Title: Engineering-Based Condition Assessment of Large-Diameter Sewers and Wastewater Structures for Structural Capacity Evaluation.
Note: This webinar is open to all, but only members will be able to access the recording. The presentation file will be available free for members and can be purchased by non-members for $10.
Overview
The condition assessment of large-diameter sewers and wastewater structures differs fundamentally from the inspection of non-man-entry pipelines. Unlike factory-produced pipes, these large conduits and structures are typically individually constructed civil engineering works, often built decades ago, with unknown or insufficiently documented structural layouts, materials, and boundary conditions.
As a result, standardized inspection and assessment approaches alone are generally insufficient to reliably evaluate their structural integrity. An engineering-based condition assessment, therefore, requires methodologies that go beyond conventional inspection standards and visual defect coding.
This presentation introduces a proven, practice-oriented assessment concept that integrates extended condition data with engineering analysis to reconstruct the existing structural systems of large sewers and wastewater structures. The approach enables:
• The systematic identification and classification of structurally relevant damage,
• The realistic representation of load-bearing mechanisms and boundary conditions, and
• The determination of the remaining structural capacity of the asset.
By combining inspection data, material assumptions, structural modelling, and damage interpretation, the methodology provides a sound engineering basis for evaluating residual load-bearing capacity. This, in turn, allows rehabilitation measures to be planned in a technically robust and cost-efficient manner, avoiding both unnecessary interventions and unacceptable structural risks.
The presentation demonstrates how extended condition assessment can be transformed into actionable engineering knowledge, supporting sustainable asset management and long-term rehabilitation strategies for large-scale wastewater infrastructure.
About Dr. Robert Stein
Dr.-Ing. Robert Stein is the Managing Associate of Prof. Dr.-Ing. 
Stein & Partner GmbH and Managing Director of STEIN Ingenieure GmbH and STEIN Infrastructure Management GmbH. He has been involved with a multitude of utility tunnelling projects. Most notably, as the project manager responsible for the approval process, planning, supervision, and quality control of the 52 km long, DN 1400 – DN 2800, deep tunnel sewage system “Emscher Kanal” for the federal state of North Rhine-Westphalia. For the construction of the Nord Stream gas pipeline running through the Baltic Sea, he was in charge of the feasibility study for a trenchless connection of the pipeline in the area of the Greifswalder Bodden on behalf of Nord Stream AG, Switzerland. Since 1995, he has published more than 100 publications, reports, expert reports, and feasibility studies. He is the author of the reference book“Wertermittlung von Abwassernetzen (Asset Valuation of Sewer Networks),” Trenchless Technology for Installation of Cables and Pipelines – 2nd Volume: Horizontal Directional Drilling (HDD), of the chapter on pipe jacking works (ATV DIN 18319) and co-author of the 4th edition of the international bestseller “Instandhaltung von Kanalisationen” (Rehabilitation of Drain and Sewer Systems) as well as of various technical articles.