Pipe reline success is all in the planning

A project to reline a sewer running alongside a river in Bolton meant a concerted planning effort for no-dig specialist Lanes for Drains. Despite many obstacles, the sewer reline works were completed within the 7-day strict timeframe, to the delight of all parties involved.

There were a number of third parties to consult during the project: United Utilities (UU) the sewer owner, Balfour Beatty Utility Solutions (BBUS) the main contractor, the Highways Agency, the Environment Agency (EA) and Network Rail.

There were also extra logistical issues to consider, such as difficult access to the site which meant that Lanes for Drains had to lift all the plant and equipment across the Middlebrook River by crane. Also because 50 metres of the riverside cycle and footpath would be closed off during the works, a temporary bridge was needed to divert users across the river. Finally, a specialist contractor had to be brought in to identify Giant Hogweed, a plant which is toxic and can cause chemical skin burns.

Peter Hopkinson of Lanes for Drains’ reline division explains:

“All the parties were consulted fully and each agency’s consent to the plans was sought so, although we first visited the site in September 2008, we did not begin work until March this year.

“The 600mm foul sewer was unsound and there was risk it could leak into the waterway during heavy rainfall so naturally the EA was involved. Network Rail had to be consulted because the working area was within eight metres of the rail track, which also ran alongside the river. The Highways Agency had to approve the part closure of the cycle path and the establishment of a diversion via the temporary bridge.

“Fortunately, although Giant Hogweed was discovered in the initial survey, by the time we began the work, the plant had gone, so we did not need to cordon off the area, but we still included provision for it in our risk assessments and method statements, and all staff were required to wear full PPE.”

For the reline itself, Lanes for Drains had had to adapt its usual procedures. Directly above the manhole chamber access point to the sewer was a metal road bridge so there was no headroom for a crane, as would normally be used to lift the weighty 105-metre long, 600mm-diameter liner into position. Instead, it was fed onto a 5-metre industrial conveyor belt and carried to the top of the scaffolding platform from where it could be guided into position by the reline crew.

Byron Carter, BBUS Planned Works Site Manager was impressed that the work was carried out to the highest standards:

“It may have taken prolonged planning, but that paid off because the project went without a hitch. Without doubt, Lanes for Drains’ extensive understanding of large-scale rehabilitation schemes, its experience of co-ordinating all the agencies involved, and its knowledge of no-dig sewer rehabilitation, ensured the success of the project.”