Modelling sewer discharge via displacement of manhole covers during flood events using 1D/2D SIPSON/P-DWave dual drainage simulations

Abstract

In urban areas, overloaded sewers may result in surcharge that causes surface flooding. The overflow from sewer systems mainly starts at the inlets until the pressure head in the manhole is high enough to lift up its cover, at which stage the surcharged flow may be discharged via the gap between the bottom of the manhole cover and the ground surface. In this paper, we propose a new approach to simulate such a dynamic between the sewer and the surface flow in coupled surface and sewer flow modelling. Two case studies are employed to demonstrate the differences between the new linking model and the traditional model that simplifies the process. The results show that the new approach is capable of describing the physical phenomena when manhole covers restrict the drainage flow from the surface to the sewer network and reduce the surcharge flow and vice versa.

Keywords::

• coupled 1D/2D modelling
• displacement of manhole cover
• manhole surcharge
• urban flooding

Acknowledgements

We are grateful to the Bradford City Council and John Blanksby for the access to the sewer network data. Thanks are due to the UK Geomatics Group, Environment Agency, and Ordnance Survey for the provision of LiDAR and digital map data, respectively. The authors would like to thank Dr Andrew Duncan for his proofreading.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the DFG - Deutsche Forschungsgemeinschaft - through Project GZ: LE 3220/1-1.