United Utilities has appointed Barhale to deliver a key project to improve water quality in the Micker Brook at Bramhall, Stockport.
The civil engineering, infrastructure and tunnelling specialist will construct a new detention tank at Bramhall Precinct car park to reduce the number of times the storm overflow operates into the brook, a tributary of the River Mersey. The shaft tank will intercept a sewer running into the existing Briarlands Combined Storm Overflow (CSO).
The contract has been awarded as part of the largest investment in wastewater infrastructure in the North West for a century. United Utilities is investing £13 billion to protect and enhance over 500km of rivers, lakes and bathing waters whilst safeguarding drinking water supplies for millions of customers.
The site sits within an area with a high water table so Barhale and the water company have collaborated closely to identify a suitable design solution. It includes diverting an 825mm diameter sewer running at 4m depth to allow construction of a 1,000m3 shaft tank using a 12.5m diameter segmented caisson sunk to an invert depth of 13.3m.
Barhale will also carry out the MEICA fit out including new pumps in the shaft, control equipment kiosks, control panels, telemetry systems and incoming power supplies. A dual rising main will be connected to the network upstream of the CSO chamber.
Nick Curtis, Regional Director – Northern Region, Barhale said:
“The project presents some significant technical challenges because of the location and site conditions and we are pleased to continue supporting United Utilities as part of their wide reaching AMP8 investment programme.
“We are already active across several aspects of the programme which are reinforcing the network’s ability to withstand storm events. They include constructing another smaller storm tank near this one in Cheadle and two more in Merseyside.
“The investment is aiming to reduce spill rates to fewer than one-in-ten-year events. The completion of the Briarlands CSO programme will be an important step towards meeting United Utilities’ target of reducing spills from storm overflows by 60% before 2030.”
Completion is scheduled for early summer 2027.
UK water companies are invited to join an upcoming webinar which will explore how the sector can take indirect potable reuse (IPR) from concept to full-scale operational reality.
James Sumsion, CEO of predictive water intelligence specialists Kohtari, says the water sector needs to take a giant leap forward, so that it can anticipate and act upon water quality issues - rather than merely react.
Ray Moulds, Sales Director at Flood Control International, takes a look at how automated sliding floodgates are supporting secondary containment at water and sewerage company sites.
With the UK government demanding a 50% reduction in storm overflow spills by 2029, the era of reactive management is over. Speaking in the House of Commons on 21 July 2025, then environment secretary Steve Reed said, “This Government will cut water companies’ sewage pollution in half by the end of the decade.”
Hear how Scottish Water has completed its £235 million Ayrshire Glasgow Resilience Project - customers across Greater Glasgow, Ayrshire and East Renfrewshire will now benefit from a more secure and resilient water supply.
Hear how United Utilities is accelerating its investment to reduce spills from storm overflows across the Northwest.
Find out more about the remarkable career opportunities on offer at WSP - scroll down to watch the inspirational video.