Northumbria Water
Locaton: Barnard Castle, County Durham
Technique: Expandit Pipe Bursting
Main Contractor: Seymour Civil Engineering
Sub-Contractor: Perco Engineering Services
Contractor Seymour Civil Engineering was building a large CSO chamber on the site of an existing one and called us in to upgrade pipes running below the adjacent road, without excavating the highway. When a rain storm occurs, a CSO - combined sewer overflow - discharges untreated wastewater from a sewer system carrying both sewage and storm water. The increased flow caused by the storm water runoff exceeds the system capacity and the sewage is forced to overflow into streams and rivers in the area through CSO outfalls.
Forming part of the sewer system connecting to the CSO, two existing pipes ran next to each other, on the same level, for a distance of 12m under a main road. The project required the Expandit mole to burst one of the 225mm pipes, enlarging the void to 300mm. It was then a simple job to insert 180mm MDPE pipe by hand and insert structural grout.
We had previously slip-lined the second pipe with 150mm MDPE, as a precaution against any ground heave damage caused by the proximity of the pipe burst. All in all, a simple two-day job for Expandit.
The existing 25” cast iron rising main carries sew...
Perco - Specialists In Trenchless Technology
