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Sulzer Pumps Wastewater Ltd

Sulzer’s field service teams lead project to reduce CSO spills

Combined sewer overflows (CSOs) present a significant issue for all utility companies in the UK during periods of heavy rainfall. Rather than waiting for AMP 8, one UK water utility has invested in a series of projects to boost flood water storage with new tanks, pumps, valves and controls installed in the worst affected sites. As a framework contractor, Sulzer was initially due to supply the pumps, but this contract was broadened to include installation and commissioning of all mechanical and electrical aspects of the upgrade.

By: Sulzer Pumps Wastewater UK Ltd

Published: June 2, 2026

Sulzer’s field service teams lead project to reduce CSO spills

The challenge

Environmental pollution is headline news in the UK, and utilities are working to significantly reduce the number of discharges of raw effluent into watercourses and the sea. Creating additional concrete storage tanks with pumping facilities requires considerable time and a large budget. The utility in this case wanted a faster, more cost-effective solution that could be delivered quickly across many sites. This comprised circular steel tanks with automated pump controls.

The solution

To deliver the project, Sulzer supplied the pumps as well as 12 mechanical and electrical teams within two weeks of instruction. In addition, Sulzer designed and built over 150 control panels to manage the operation of the pumps and actuated valves. The teams have installed pipework, pumps, valves and controls across 78 sites with more being completed each week. In addition, Sulzer’s teams have also delivered temporary submerged aerated filter (SAF) units and reed bed schemes.

Customer benefit

With Sulzer’s support, the water utility has ensured every pump matches its duty requirements for long-term reliability. The pump control panels include the ability to add future automation that will enable a seamless, operator-free solution. As a result, the water authority has started making improvements to CSO systems before AMP 8 budgets are made available. With the success of Phase 1, Sulzer has been awarded a contract for Phase 2, which will involve another 90 sites.

“Our speed of response and the wide skill sets of our field service teams were crucial to the success of this project.”

Dave Higgins, Sulzer Project Manager

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[email protected]

sulzer.com

For More Information, contact us at https://www.sulzer.com/

Sulzer’s field service teams lead project to reduce CSO spills

Combined sewer overflows (CSOs) present a significant issue for all utility companies in the UK during periods of heavy rainfall. Rather than waiting for AMP 8, one UK water utility has invested in a series of projects to boost flood water storage with new tanks, pumps, valves and controls installed in the worst affected sites. As a framework contractor, Sulzer was initially due to supply the pumps, but this contract was broadened to include installation and commissioning of all mechanical and electrical aspects of the upgrade.

Sulzer accelerates floodwater storage initiative for major water utility

Environmental pollution has become a pressing issue in the UK, with water utilities under increasing pressure to reduce discharges of raw effluent into rivers and seas. The water utility company responsible for maintaining water quality across a vast region, set an ambitious target of a 20% reduction in spills across 900 combined sewer overflows (CSOs) by 2025. Working in close partnership with Sulzer, it embarked on a major spill reduction initiative that has delivered upgrades to over 65 sites in a matter of months rather than years.

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Alderney WTW (2023)

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Burnley WwTW Catchment Strategy (2023)

The Burnley integrated catchment scheme is one of United Utilities’ (UU) largest AMP7 projects with a value of £77m. The project is being delivered by UU’s construction delivery partner (CDP) framework by Advance-plus, a joint venture between MWH Treatment, J Murphy & Sons (JMS) and Stantec UK. The project commenced in 2020 and through two […]

Guildford STW (2023)

Guildford Borough Council (GBC) are progressing with the development of approximately 41 hectares of brownfield land located along the west bank of the River Wey as it runs through central Guildford and north through Slyfield Industrial Estate. Guildford Sewage Treatment Works (STW) lies within this land and requires relocation in order to enable the development […]

Hampton Loade WTW (2023)

Hampton Loade WTW treats raw water from Chelmarsh Reservoir, located approximately two miles north-west of the site. The reservoir is supplied by the river intake pumps located within the intake building immediately adjacent to the River Severn. The maximum flow that can gravitate to the works from the reservoir is 130-135 megalitres/day (MLD). To increase […]

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Knostrop Sewage Treatment Works (STW) is Yorkshire Water’s largest wastewater treatment site, serving a population equivalent of 990,000 and a full flow to treatment (FFT) of 5600 l/s. The WINEP Programme requires Yorkshire Water (YW) to achieve compliance with the new Total Phosphorus and Total Iron permit levels at 80 wastewater treatment works, including Knostrop. […]

Newthorpe STW (2023)

North-west of Nottingham and separated by the River Erewash, two of Severn Trent’s sewage treatment works are situated within 2.5km of each other; part of the legacy of the times of the public statutory undertakers. Heanor Milnhay STW in Derbyshire has a dual-stream process, with part of the flows going through trickle filters and the […]

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Burnley WwTW Catchment Strategy (2022)

The Burnley Integrated Catchment Scheme is one of United Utilities largest AMP7 projects with a value of over £60m which commenced in 2020. The project is being delivered by Advance-plus, a joint venture between MWH Treatment, J Murphy & Sons and Stantec UK; United Utilities’ framework construction delivery partner (CDP). In UK Water Projects 2021 […]

Stoke Bardolph STW - Anaerobic Digestion (2022)

Stoke Bardolph Sewage Treatment Works (STW) is Severn Trent’s second largest STW and serves a population of c. 620,000. The site is also a major regional sludge centre, meaning it takes a high volume of sludge imports from other sites in the region. Stoke Bardolph has a sludge treatment capacity equivalent to a population of […]

Strongford STW - THP & LTP (2022)

Strongford STW is a major sewage treatment works serving the population equivalent of circa 350,000 from Newcastle-under-Lyme and Stoke-on-Trent. The site’s sludge treatment facility provides a major centre for regional operations. Based on a forecast increase in population, it was identified that an increase in treatment capacity would be required to accommodate the local growth. […]

Blackburn and Darwen WwTWs (2021)

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Heigham WTW (2021)

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Kineton STW (2021)

The Kineton STW required investment in AMP7 due to the introduction of a 0.5mg/l total phosphorus effluent limit, which comes into force by the end of December 2021. The new works is designed to cater for flows from Kineton, Butlers Marston and Radway equating to a combined design horizon population equivalent of 3,946. The existing […]

Lletty Brongu & Ruthin STWs (2021)

Welsh Water raised a programme of quality schemes for completion in AMP6 to address tightening of phosphorus permits set by Natural Resources Wales (NRW) at ten wastewater treatment works. Some of the sites in the programme were subject to a new total phosphorus (TP) permit of 0.5 mg/l T-P and required the installation of a […]

Blackburn and Darwen WwTWs (2020)

Blackburn WwTW, located at Samlesbury near Blackburn, serves a population equivalent (PE) of approximately 400,000 and discharges final and storm effluent to watercourses that are tributaries of the River Darwen, feeding into the River Ribble estuary and ultimately into the bathing waters of the Fylde coast in the Irish Sea. Over the last 12 months, […]

Blackburn and Darwen WwTWs (2019)

Both Blackburn WwTW and Darwen WwTW discharge final and storm effluent to watercourses that are tributaries of the River Darwen, feeding into the River Ribble and ultimately impacting on the bathing waters of the Fylde coast. Following on from the Blackburn and Darwen WwTWs (2017) article and Blackburn and Darwen WwTWs (2018) article, both published […]

Davyhulme WwTW Modernisation Project (2019)

Davyhulme Wastewater Treatment Works (WwTW) is United Utilities (UU) largest, serving over 1.3 million customers across Greater Manchester. Built in 1894, it has seen continuous development in wastewater treatment including the invention of the activated sludge process (ASP) by Ardern & Lockett in 1914. Incoming flows from the combined sewer network can reach 30m3/s, the […]

Earl Shilton STW (2019)

Earl Shilton Sewage Treatment Works (STW) is situated in south west Leicestershire and serves a population equivalent of 11,833 comprised mainly from domestic sources from Earl Shilton and Barwell. There has been a STW in this location since the 1960s and the current process workstream includes preliminary treatment, primary settlement, secondary filtration, secondary settlement and […]

Kendal WwTW (2019)

Kendal WwTW is the main treatment facility for the area servicing a large residential and tourist catchment, with a population equivalent of 82,384. The works has an existing consent of 25 mg/l biological oxygen demand (BOD) 45mg/l suspended solids, 5 mg/l ammonia, and an annual average phosphorus permit of 1 mg/l, with a flow to […]