Sewer pipe deterioration is driven by a finite number of root causes and processes. Thus, it should be both feasible and advantageous
to have a uniform classification system that can be universally applied in sewer deterioration modelling and asset management.
However, a literature review of existing classification systems revealed several problems and inconsistencies, and no widely adopted system.
This work proposes a uniform classification system that can be used for different purposes in the fields of gravity pipe deterioration and asset
management. This paper focuses on separated sewer systems, but the proposed system can be easily adapted for combined sewer and storm water
systems.