A sewer network’s structural condition is an important parameter for medium-term planning support purposes and for the development of rehabilitation strategies. A variety of approaches to classify structural condition have already been developed, but no universal standard so far exists. This article presents the findings of a joint project funded by the German Federal Ministry of Economic Affairs called ‘Development of a Standard to Evaluate and Classify the Structural Condition of Sewers’ (SubKanS).

The project identified wear and tear on a sewer section based on its individual type of damage and its severity using different weighting that is grounded in sewer network operators’ requirements and expectations of a classification of this kind. It is then classified in a category of structural conditions. The project calibrated model parameters and assignment rules by drawing from expert assessments and evaluations of approximately 100,000 sewer sections.