Barhale to Deliver Storm Overflow Reduction Project in Stockport 2026

• Key Points

• Barhale has been appointed by United Utilities to construct a new 1,000m³ underground detention tank at Bramhall Precinct car park in Stockport, to reduce storm overflow discharges into Micker Brook.
• The project forms part of United Utilities’ wider £80m investment in Stockport to build more than 19,000m³ of new stormwater storage across five sites, including Cheadle, Bramhall, Hope Street and the Stockport wastewater treatment works.
• The new shaft tank will intercept a sewer feeding the existing Briarlands Combined Storm Overflow (CSO), reducing the frequency of overflows into the brook, a tributary of the River Mersey.
• Barhale will also complete the MEICA fit-out, including new pumps, control equipment kiosks, control panels, telemetry systems and incoming power supplies.
• Work is scheduled to begin in January 2026, with Bramhall Precinct car park and part of a Public Right of Way footpath temporarily closed for the duration of construction, expected to last up to 12 months.
• Completion is targeted for early summer 2027, with United Utilities aiming to reduce spill rates to fewer than one-in-ten-year events at this site.
• The collaboration is part of United Utilities’ broader commitment to reduce spills from storm overflows by 60% before 2030 under its £3bn Better Rivers programme.
• Local traders in Bramhall have expressed concerns about the long closure of the precinct’s car park, which they rely on for café and shop customers, though United Utilities says the site is essential for the tank’s construction.

 Stockport (Manchester Mirror) July 09, 2026 – Micker Brook is set to benefit from a major new stormwater storage project as Barhale has been appointed to deliver a key United Utilities scheme to reduce the frequency of storm overflow discharges into the waterway.

The civil engineering, infrastructure and tunnelling specialist will construct a new underground detention tank at Bramhall Precinct car park. The project is designed to intercept a sewer that currently runs into the existing Briarlands Combined Storm Overflow (CSO), significantly reducing the number of times the CSO operates during heavy rainfall and discharges into Micker Brook, a tributary of the River Mersey.

As reported by the New Civil Engineer, the contract has been awarded as part of the largest investment in wastewater infrastructure in the North West for a century, underscoring the national significance of the project.

How will the new detention tank work?

The 1,000m³ shaft tank will be built underground within Bramhall Precinct car park. According to United Utilities, the tank will store excess stormwater during periods of heavy rain, preventing it from reaching the CSO and being released into the brook.

As explained on United Utilities’ local news page, the new underground storm water storage tank means the car park will need to be temporarily closed during construction, and a section of the Public Right of Way footpath will also be closed for a short time.

Barhale will also carry out the full MEICA (mechanical, electrical, instrumentation, control and automation) fit-out, including:

• New pumps in the shaft
• Control equipment kiosks
• Control panels
• Telemetry systems
• Incoming power supplies.

What is the wider Stockport investment?

This Bramhall scheme is one of five projects United Utilities is rolling out across uk/local/stockport/">Stockport under an £80m investment programme. As reported by United Utilities in November 2025, the company will build more than 19,000m³ of new storage across the borough – equivalent to seven and a half Olympic-sized swimming pools – to reduce the frequency of combined sewer overflow operations during heavy rain.

The five sites include:

• Cheadle Golf Club (500m³ tank, work started and expected to finish by the end of 2026)
• Briarlands Close CSO in Bramhall (1,000m³ tank, work starting January 2026, up to 12 months)
• Lumb Lane in Bramhall (320m³ tank, work starting February 2026, up to 12 months)
• Hope Street near Stockport town centre (650m³ tank, work starting spring 2026, completion by end of 2028)
• Stockport wastewater treatment works in Cheadle Heath (more than 16,700m³ of new storm tanks, initial work early 2026, completion by end of 2028).

These projects will help improve water quality in both Micker Brook and the River Mersey.

How long will the Bramhall Precinct closure last?

Work on the Briarlands Close CSO is due to start in January 2026 and is expected to take up to 12 months to complete, according to United Utilities.

During this period, Bramhall Precinct car park will be closed for the duration of the works while the underground tank is built, and a section of the adjacent footpath will also be temporarily closed.

United Utilities has indicated that alternative parking is available at Meadway Car Park East, 5 Meadway, Bramhall, Stockport SK7 1JZ, and that the car park and footpath will be put back and reopened once construction is finished.

What are the environmental targets?

The investment is aiming to reduce spill rates at the Briarlands site to fewer than one-in-ten-year events, a significant improvement from current frequencies.

As stated by United Utilities, the completion of the Briarlands CSO programme will be an important step towards meeting the company’s target of reducing spills from storm overflows by 60% before 2030, part of its wider Better Rivers programme focusing on water quality and river protection across the North West.

Nick Curtis, Regional Manager at Barhale, said:

“It is an absolute priority to help protect rivers and the wider environment by reducing spills from storm overflows. We have worked closely with United Utilities to shape each of the project approaches and are looking forward to making our contribution to the Better Rivers project,” as reported on Barhale’s LinkedIn post.

How have local businesses reacted?

Local traders in Bramhall have voiced concerns about the long closure of the shopping precinct’s car park, which they rely on for customers. As reported by the BBC, business owners said the closure “threatens our café” and could impact livelihoods, given that many shoppers park at the precinct before visiting nearby shops and eateries.

United Utilities has responded that, from an environmental perspective, the site is essential for the tank’s construction, and that the long-term goal is to create significant environmental benefits for the local community.

The company has also said its onsite team will do all they can to minimise noise, dust and vibration, and that local residents and businesses will be regularly updated throughout the programme.

How will this project affect water quality in Micker Brook and the River Mersey?

The new detention tank at Bramhall will directly reduce the volume of stormwater and sewage discharged into Micker Brook during heavy rainfall, improving water quality in the brook and, downstream, in the River Mersey.

By intercepting the sewer feeding the Briarlands CSO and storing excess flow in the underground tank, the scheme will limit the frequency of combined sewer overflow operations, helping to move spill rates towards fewer than one-in-ten-year events at this location.

When combined with the other four Stockport projects, the overall investment will deliver more than 19,000m³ of additional storage, creating a regional buffer that should substantially reduce the load of pollutants entering Micker Brook and the Mersey during storm events.

Background: United Utilities’ Better Rivers programme and Stockport infrastructure investment

The Barhale appointment is part of United Utilities’ £3bn Better Rivers programme, which aims to improve water quality and protect more than 300 miles of waterways across the North West.

Under this programme, United Utilities has selected multiple contractors, including Barhale, to deliver network infrastructure upgrades focused on increasing stormwater storage and reducing CSO activations. Barhale has already secured a triple package under Better Rivers, with projects at Cheadle in Stockport, and Wheatfield Close and Thornton in Merseyside, in addition to the Bramhall scheme.

The wider Stockport investment of £80m represents a significant upgrade to the borough’s wastewater network, adding storage equivalent to seven and a half Olympic pools and targeting substantial reductions in spill frequency across multiple sites, including Micker Brook and the River Mersey catchments.

This aligns with United Utilities’ strategic commitment to reduce spills from storm overflows by 60% before 2030, a key environmental target underpinning its AMP8 investment plans and its regulatory obligations to improve river health.

Prediction: How this development can affect local residents, businesses and the environment in Stockport

For residents living near Micker Brook and the River Mersey, the project is likely to lead to cleaner waterways, with fewer visible sewage discharges and improved ecological conditions over time, contributing to better local amenity and biodiversity.

Local businesses in Bramhall Precinct may face short-term disruption due to the car park closure and reduced footfall during the 12-month construction period, but the long-term environmental gains and potential restoration of the car park and footpath could support more sustainable local commerce once the project is complete.

For the wider Stockport community, the cumulative effect of the five storage projects should mean fewer storm overflow events across the borough, reducing the risk of contaminated water entering gardens, streets and public spaces during heavy rain, and supporting United Utilities’ 60% spill reduction target by 2030.

Environmentally, the increased storage capacity and reduced CSO activations are expected to improve oxygen levels and reduce pollutant loads in Micker Brook and the River Mersey, supporting fish populations and other aquatic life, and contributing to broader regional river restoration goals.