Vulnerability hotspot mapping (VHM) of sewer pipes based on deterioration factors

ABSTRACT

A decentralized, and sustainable sewer inspection plan at the city scale demands multiple inspection methods with different areas of impact. While sewer deterioration models offer great areas of impact, spatial mapping can assess the vulnerability of the system without prior knowledge of the pipe’s structural health condition. In this study, we assess and prioritize sewer deterioration factors such as pipe age, material, sewer type, node degree, flow velocity, and surface vegetation for vulnerability hotspot mapping of a sewer system in Dresden, Germany. The validation and sensitivity analyses revealed that flow velocity, pipe age, and surface vegetation are the most sensible factors to model, respectively. The linear model resulted in 76% efficiency and a mean squared error of 0.918 while it was improved with a random forest algorithm which points out vulnerability mapping potential as an early sewer inspection method at the city scale.

KEYWORDS:

• Vulnerability hotspot mapping
• sewer vulnerability detection
• sewer deterioration factors
• sewer ex-infiltration

Acknowledgements

The authors would like to announce their gratitude to the Deutsche Forschungsgemeinschaft (DFG) and Stadtentwässerung Dresden and are grateful to the colleagues of the Institute of Urban and Industrial Water Management for their support in this review.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Thanks to Deutsche Forschungsgemeinschaft (DFG) grant number 402833446 regarding the funded project entitled INCIDENT (Utilising sewer network characteristics for the identification of the optimized point-based monitoring systems)