Stockport looks to tackle A555 flooding woes

Further actions to reduce the risk of flooding on the link road to Manchester Airport, a headache since the dual carriageway’s 2018 completion, have been presented to local councillors.

The 13km Manchester Airport eastern link road road links the A6 to the motorway network around Manchester Airport.

Long seen as crucial to improving infrastructure for Stockport, south Manchester and north Cheshire, the completion of the A555 beyond the 1995-delivered section between Handforth and Bramhall was adopted as transport policy in 2001, but it took a further 17 years for the relief road to be fully completed.

This saw Carillion and Morgan Sindall deliver the sections at each end to complete the project.

As set out in a report considered by Stockport Council’s Bramhall and Cheadle Hulme South area sub-committee this week, lower sections of the route have in recent years experienced flooding during periods of prolonged and intense rainfall, with issues including the highway drainage system and pumping infrastructure.

The route was affected during floods in July 2019, subsequently being included within Stockport Council’s Section 19 Flood Investigation Report, an investigation that identified several contributing factors including exceedance of attenuation pond storage, limitations in pump station capacity, and pressure on the wider drainage network during extreme rainfall events.

Stockport then commissioned works including drainage reviews, improvements to pumping infrastructure, cleansing of storage tanks and drainage infrastructure, inspection and maintenance of receiving watercourses and developing further drainage.

The report said that while these measures had “improved operational resilience,” parts of the A555 remain vulnerable during extreme weather events, as was seen with flooding over New Years Eve 2024, when the River Mersey at Brinksway, Lady Brook at Bramhall Green and Poise Brook all recorded record water levels.

With freezing weather following the storms, this flood event closed the A555 for a time, the stretch of road to the north of Handforth being particularly badly afflicted.

Specific measures taken since include the completion in July of a drainage diversion at Woodford Recreation Ground, diverting drainage from the Highfield Parkway housing estate and Woodford Rec to the north of the A555, which previously discharged into the A555 drainage system upstream of the existing Hall Moss Lane pump station, creating additional load.

This drainage has been returned to its original route into Spath Brook to the north side of the A555, which has the capacity to take on the load according to the council team’s hydraulic modelling.

The next stage, Stockport said, is increasing the overall pump capacity at Hall Moss Lane, with work planned to start later this year. Works to help prevent the station being overwhelmed include replacement of existing equipment and increasing pumping capacity to improve the rate at which water can be removed from the drainage system during extreme weather events.

In the coming year, the report added, the council will look at improvements to the pond capacity at the Oil terminal gyratory pond. Following the downstream improvements at the Hall Moss Lane pump station, it is proposed to increase the discharge rate from the ponds.

The thinking is that an increase in discharge rate will reduce the drain-down time and allow for more flow to reach the pumping station outside of critical storm events, mitigating the issue of the pond overtopping during periods of prolonged and heavy rainfall.

• This story has been updated to provide further information on the timeline of the A555’s delivery