Cadent has nearly completed a £1 million project to divert the River Mersey at Didsbury near Stockport, Greater Manchester to safeguard gas supplies.
Erosion from the watercourse threatened one of the main gas feeds into Manchester, the gas distributor said.
A 400 metre stretch of the river is being moved 40 metres back to its original 1960s channel to safeguard the high pressure pipe which feeds around 250,000 homes and businesses in Manchester.
The project has involved 18 months of “meticulous” planning and extensive liaison with the Environment Agency, as well as the local authorities and landowners. Construction began in June and is due to finish by the end of next month.
Engineers have worked on both sides of the river and have been straightening and widening the channel and grading back the banks to provide a more effective flood plain. Due to one section of the river being wider at one point a “speed bump” called a riffle will be installed to slow the water down.
Matthew Goode, network supervisor at Cadent, who is heading up the project described it as “unique”.
“It’s the first time we’ve ever done a project of this type on this scale. It has been a major challenge but it’s progressing really well and once it’s complete we won’t need to come back again.
“Our job is to keep the gas flowing to homes and businesses across the north west and when this gas pipe was laid in the 1960s, it was well away from the river.
“However, over the last 50 years, through a natural process of erosion, the river’s course has changed. If we didn’t take action, the river would erode the soil under the pipe and leave it unsupported, potentially damaging the pipe and jeopardising gas supplies.”