Client: Thames Water Utilities Ltd
Project start: October 2008
Project finish: March 2009
Location: Narrow Street, London, E14
New wet well, rising main, gravity sewer and manholes to alleviate the risk of sewer flooding
This design and build project was required by Thames Water to prevent sewer flooding to properties along Narrow Street on the Isle of Dogs.
Narrow Street is a particularly sensitive location in which to be carrying out construction activities as it is home to a number of high profile residents including former Foreign Secretary Lord David Owen, the actor Sir Ian McKellen and David Owens, the current Chief Executive Officer of our client, Thames Water Utilities.
The project involved sinking a 6.2m deep, 2.4m circular shaft to enable construction of a wet well, constructing a valve chamber, laying a rising main and construction of a new manhole to allow a gravity feed to an existing sewer. Additionally, we were required to lay 90m of new 150mm diameter sewer with 3 new 1200mm diameter manholes and make 9 lateral connections from existing properties. The new 150mm sewer was laid at depths of between 3m and 4m, generally by open cut methods.
The project encountered some challenges, principally relating to difficult ground conditions. Groundwater was a recurring problem on the project, as we were working within 7m – 8m of the River Thames, and we also encountered existing basements and the original walls of Narrow Street. Numerous existing services were also encountered and had to be dealt with whilst excavation works progressed. Thames Water employed an archaeological survey company to maintain a watching brief on the project whilst we were excavating.
We worked hard on this project to maintain a clean and tidy work area and to ensure that our site team worked cooperatively with the local residents. Our efforts were rewarded with a letter from one of the residents praising the site team for their ‘helpfulness and pleasantness’.