Double manholes in Odense

In the period from 2002-2009, Aarsleff Pipe Technologies worked closely together with Odense Water Ltd on a large renewal project with focus on double manholes. We renewed a total of 100 double manholes. The projects consisted of a number of sub-projects in different parts of the city, e.g. the area around the street Steffensvej in the urban quarter of Pårup. That specific sub-project included renewal of 13 double manholes, renewal of approx. 850 metres of DN200 mm wastewater pipe and 55 wastewater laterals by means of Aarsleff CIPP Lining.

Up to 2001, Odense Water Ltd had through a number of years experienced quite some problems with double manholes. Among other things, the problems consisted of infiltration and overflow of water from rainwater to wastewater and of elevated intermediate covers. The result was mixing of rainwater and wastewater.

Odense Water Ltd and Aarsleff Pipe Technologies had worked closely together to prepare an extensive plan for the entire project which had the following main features:

• Breaking up of manhole floor in rainwater section
• Preliminary investigation, registration/indication and measurement of laterals
• Lateral renewal by means of Aarsleff CIPP Lining
• Renewal of approx. 300 wastewater laterals
• Renewal of 100 manholes with DS benching, intermediate covers and DN425 mm manhole riser
• Possible cancellation of intermediate manholes
• Repair of possible disconnections

One of the results of our work was a water intrusion reduction of up to as much as 90% which reduced the load on the wastewater system considerably.