Penrith Pipe Bridge Replacement, Cumbria

Bethell have been involved as a “Category A” Framework Partner with United Utilities for over 10 years. Our role within the Asset Maintenance Support Framework (AMS) is to provide civil engineering solutions to maintain UU’s vast network of Water Treatment Works, Sewage Works, Reservoirs and other infrastructure assets. At Penrith we were appointed to provide a design and construct solution to replace a 38m span pipe bridge over the River Eamont.

The existing cast iron pipe bridge was badly corroded and supported a 375mm diameter sewage overflow pipe over the River Eamont. The pipe bridge was beyond its design life and failure of the structure would cause an unacceptable environmental incident. Various maintenance options were considered including strengthening the existing structure and new protective paint applications, however these proved too costly when considering the whole life cycle of the asset. The most economical long-term option was to replace the whole of the bridge structure with a new galvanised lattice girder supporting an upsized 450mm ductile iron pipe. 

The new structure was delivered to site in four new sections and then assembled next to the river on temporary supports. Enabling works consisting of a 200 metre long temporary haul road, hardcore lay-down areas and reinforced concrete foundations were required to position a 500 tonne mobile crane. The crane remained in position for two days to remove the existing bridge in one section and then lowered in the new 25 tonne structure into position on the new abutments. Other works included replacement of the pipe work either side of the bridge plus modifications to the siphon entry and chambers that formed within the masonry abutments.