Ditton Road, Widnes
Client: United Utilities.
Project Description/Main Operations:
- Diversion of a 2300mm dia. sewer whilst maintaining flows, required to facilitate the construction of the new Mersey Gateway Bridge.
- Construction of 4 no. segmental shafts, 6.00 & 7.50m dia.
- Completion works to above, including reinforced concrete bases, benching, backdrops and precast concrete roof slabs.
- Abandonment of existing sewers up to 2300mm dia.
- Construction of a 2100mm dia. tunnel approx. 460m in length, by Pipejacking techniques, using a Backacter Tunnelling Machine.
- Particular challenges included tunnelling through contaminated ground with Hydrogen Sulphide present. For this operation, the underground personnel wore hooded masks with an air supply fed continuously to them from the surface.