Nominate/Submit Case Studies

Become a Featured Company

Donegan Civil Engineering

CSO Chambers and Detention Tank – Aqueduct Road and Bolton Road, Blackburn

Two new CSO chambers and a 650m³ detention tank resolving separate unsatisfactory discharges to the River Darwen

By: Valentine Donegan

Published: August 6, 2026

CSO Chambers and Detention Tank - Aqueduct Road and Bolton Road, Blackburn

Client: United Utilities

Project Description / Main Operations

As part of United Utilities’ larger Blackburn UIDs scheme, V J Donegan & Co Ltd were awarded this project to resolve 2 separate unsatisfactory discharges into the River Darwen.

The resultant work ensures that the new combined sewer overflow (CSO) chambers comply with the Environment Agency requirement to reduce the number of spills per year and to screen any spills. The 2 working areas were situated near the junction of Aqueduct Road and Bolton Road in Blackburn.

Scope and method – Aqueduct Road:

Construction of a 10.30m internal diameter detention tank with 650m³ storage, including backdrop pipework, storm pumps and rising mains.
Modifications to an existing brick CSO chamber, including extending the external walls and constructing internal reinforced weir walls, complete with powered screen.
Open-cut pipework ranging from 225mm to 900mm diameter, with manhole chambers ranging from 1200mm to 3000mm diameter.

Scope and method – Bolton Road:

Construction of a reinforced CSO chamber complete with powered screen.
Open-cut and trenchless pipework ranging from 375mm to 1200mm diameter.
Manhole chambers ranging from 1500mm to 3000mm diameter.

For More Information, contact us at http://www.donegan.co.uk

Underground Pumping Station - HMP Featherstone, Wolverhampton

Design, build and installation of an underground pumping station on the extension works at HMP Featherstone

Twin Storage Shafts - Langdale Way, Frodsham

Two shafts - 20.00m and 9.00m diameter - sunk within the playing field of a primary school

TBM Rail Crossing - Croes Atti, Flint

A 40m TBM drive beneath the Chester-Holyhead railway line in very wet clays with large boulders

Tank Sewer Storage for DG5 Flooding - Tunstead Milton, High Peak

110m of 1050mm tank sewer providing 85m³ of storage, removing properties from the DG5 flooding register

Surface Water Detention Tank and Sewer Upsizing - Arnold Close, Dukinfield

A 10.30m surface water detention tank and 550m of sewer upsizing, taking four properties off the flood register

Strategic Transfer Sewer Tunnelling - Paisley, Renfrewshire

1.5km of micro tunnel pipejacking forming a new strategic transfer sewer through Paisley, Renfrewshire

Storm Water Storage Shaft - Crow Lane, Chesterfield

A 15.00m diameter shaft sunk to 25m depth, providing over 3,500m³ of storm water storage for Yorkshire Water

Storm Water Storage Shaft - Brunswick Road, Altrincham

A 20.00m diameter storage shaft providing over 5,000m³ of storm water capacity, sheet piled through unstable upper strata

Storm Storage Shaft and Pipejacked Tunnel - St Dunstan's Way, Bradford

A 20.00m diameter, 23m deep segmental shaft and 130m of pipejacked tunnel for Yorkshire Water

Sheet Piled Trench and Concrete Culvert - Paradise Street, Liverpool

A 200m sheet piled trench and 3m x 3m in-situ reinforced concrete culvert on Liverpool's city centre development

Shaft and Outfall Construction - Blackpool Coastal Protection Scheme

A shaft within a sheet piled cofferdam and a new pumping station outfall, built to the tide on Blackpool seafront

Sewer Diversion for the Metrolink Second City Crossing - Manchester

Sewer diversion and replacement across Manchester city centre for the Metrolink Second City Crossing

River Bank Stabilisation and Sewer Reconstruction - Courtaulds, Preston

Over 400m of permanent sheet piling stabilising the River Ribble bank and reconstructing a collapsed foul sewer

River Bank Stabilisation and Pipebridge Replacement - Bridge Farm, Wilmslow

River Bollin bank stabilisation to prevent collapse of an existing pipebridge

Precast Concrete Culvert Installation - Brooks Lane, Middlewich

75m of precast concrete culvert and associated pipelines for United Utilities at Middlewich

Pipejack Beneath the West Coast Main Line - Clifton WwTW, Penrith

A 1500mm pipejack beneath the West Coast Main Line, plus a new pumping station shaft underpinned in hard sandstone

New CSO and Storm Detention Tank - St Helens

Principal Contractor delivery of a new CSO and 700m³ storm detention tank on United Utilities' £10m Better Rivers investment in St Helens

Micro-Tunnel Rail Crossing - Silecroft FTS, Millom

A 100m micro-tunnel rail crossing driven with a Herrenknecht TBM, with shafts founded outside Network Rail's zone of influence

Mains Duplication Tunnelling - Heronbridge, Chester

250m of 1800mm diameter tunnel driven in sandstone, plus 1400m of 1200mm diameter water main

Live Sewer Diversion for the Mersey Gateway - Waterloo Road, Widnes

Diversion of a 1050mm diameter sewer under live flow conditions to facilitate the Mersey Gateway Bridge

Hospital Sewer Connection - The Spire, Didsbury

Sewer connection for a new private hospital, formed by caisson shafts and a 20m pipejack

Foul Water Storage Shaft - Newlands Court, South Shields

A 25.00m diameter underpinned shaft providing over 4,000m³ of foul water storage for Northumbrian Water

Foul Water Detention Tank - Bedford Street, Darlington

A 25.00m internal diameter detention tank providing 2,500m³ of additional foul water storage on a Northumbrian Water flood relief scheme

Emergency Sinkhole Stabilisation - Mancunian Way, Manchester

Emergency stabilisation of a large sinkhole in a major dual carriageway, with six segmental shafts and 125m of tunnel in sandstone

Detention Tank, Pumping Station and CSO - Cookesmere Lane, Sandbach

A new foul detention tank, pumping station and screened CSO chamber taking eighteen houses off the flood register

Detention Tank and CSO Screening - Witton Park, Blackburn

A 20m internal diameter, 4,500m³ detention tank with self-cleansing vac-flush system, resolving an unsatisfactory intermittent discharge to the River Blakewater

Detention Tank and Screened CSO - Darwen WwTW and Clarence Street, Lancashire

A 15.00m diameter caisson detention tank and pumping station with over 1,000m³ capacity, plus a screened CSO chamber underpinned around a live 4.00m tunnel

CSO Chambers and Detention Tank - Aqueduct Road and Bolton Road, Blackburn

Two new CSO chambers and a 650m³ detention tank resolving separate unsatisfactory discharges to the River Darwen

Caisson Shafts for Micro Tunnelling - A19 Silverlink, North Shields

Three caisson shafts for micro tunnel pipejacks on the A19 Silverlink congestion relief scheme at North Shields

Caisson Shaft Storm Tank - Gillingham WRC

A MEICA-ready, watertight caisson storm tank increasing storm storage capacity at Wessex Water's Gillingham WRC

Caisson Shaft and Sewer Replacement - Upperpassmonds Road, Rochdale

A 10.30m internal diameter caisson shaft sunk through wet sandy clays, with augerbore, timber heading and on-line sewer replacement

Caisson Detention Tank - Tewkesbury Drive, Lytham St Annes

A 15.00m diameter caisson detention tank taking eleven homes off the flood register

2300mm Sewer Diversion for the Mersey Gateway - Ditton Road, Widnes

Diversion of a 2300mm diameter sewer through contaminated ground, with 460m of 2100mm diameter pipejacked tunnel

Airside Drainage and Utilities Infrastructure - Manchester Airport

Airside drainage, fire main and utilities infrastructure supporting the Pier 2 transformation at Manchester Airport

Back Alley Sewer Replacement - Alwyn Street, Liverpool

Sewer replacement in the back alleys of terraced housing, with full reconstruction of over 20 rear yards

Cable Tunnel in Dolerite - Dewar Place, Edinburgh

A 200m segmental tunnel driven through dolerite of up to 190MPa in the centre of Edinburgh

Wilmslow WwTW – Civil Engineering Works

Reinforced concrete bases & chambers, containment & access upgrades, and ducting & drainage to create a clean, MEICA-ready interface

Westminster Road, Macclesfield

Construction of an access chamber onto an existing brick culvert to provide an outfall for surface water

Failsworth WwTW

Client: LiMA for United Utilities Value: £550,000 Project Description / Main Operations As part of a new Waste Water Treatment centre in Failsworth, Greater Manchester, there was a requirement to cross Green Lane, opposite the site, with several ductile iron pipes ranging from 1000mm to 250mm. Additionally, 3 no. 150mm ducts for telemetry were also […]

Goole Pumping Station – Goole, East Yorkshire

Reducing flood risk to surrounding residential and industrial areas in Goole

Green Asset Lab Enabling Works

New Victoria - Segmental Shaft Sinking, Manchester

Client: Vinci Project Description/Main Operations The VJ Donegan Civil Engineering team were approached by Vinci two years before works on the project commenced and developed the operations to enable both the diversion of an existing outfall running across the site, and also provide a new site connection for combined flows into the surrounding network. Scope […]

Chester Northgate Tunnelling – Chester City Centre

Client: Vinci PLC / Cheshire West & Chester City Council Value: £2,700,000 Project Description/Main Operations V J Donegan & Co Ltd were approached to work alongside Vinci PLC and Cheshire West & Chester City Council to provide a constructable solution for a new surface water outfall, from the Northgate Development Phase 1 in the heart […]

The Airfields, Deeside

Large-diameter caisson and dewatering for regeneration infrastructure at the former RAF Sealand.

Medlock CSO Screening

Client: Costain / United Utilities Value: £2,200,000 Project Description/Main Operations V J Donegan and Co Ltd was enlisted to collaborate with Costain in via their MSP Framework in partnership with United Utilities on the Medlock CSO Screening project. This initiative aimed to minimize the environmental impact of combined sewer overflows into the Medlock watercourse, an […]

Liverpool Waters, Stanley Dock – Civil Engineering Projects, Liverpool

Client: Excalon / Vital Energi Value: £600,000 Project Description/Main Operations V J Donegan & Co Ltd were approached by Excalon to provide a solution for laying 2 no. 710mm dia. gas pipes across Great Howard Street. Due to the high concentration of utility services within Great Howard Street it was deemed that an open-cut technique […]

Fujiclean Tank Installation – South Cheshire

Pioneering the FujiClean wastewater treatment system at Calverhall in collaboration with Costain and United Utilities.

Caisson Shaft Installation, York

Innovatively installing three deep caisson shafts under a challenging high‐water table for Moortown Construction and Kier’s £850,000 York development

Hathershaw Fields CSO & Bardsley WwPS (2023)

Improving water quality in the River Medlock by installing new powered screens at existing sites in Oldham, Greater Manchester

Blackburn and Darwen WwTWs (2022)

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 estuary and the bathing waters of the Fylde coast in the Irish Sea. At Blackburn WwTW, which provides treatment for a population equivalent (PE) of approximately 400,000, construction of the […]

Blackburn and Darwen WwTWs (2021)

Blackburn WwTW was constructed in the 1960s and principally treats domestic crude sewage from the Blackburn catchment, with two major additional contributions; a high strength trade effluent from the InBev brewery and an ammonia rich return liquor flow from the sludge treatment plant. The key river water quality/water framework directive parameters within the revised environmental […]

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 […]

Medlock Quality Programme (2019)

Medlock Quality Programme is part of United Utilities AMP6 investment programme across the North West and is the third Nereda® Reactor Plant to be operated by United Utilities. The scheme can be split into two distinct areas: (i) the upgrade of Failsworth WwTW to meet the new discharge consent and reduce the volumes of spills […]

Paisley Tunnel Project (2019)

Scottish Water’s £17m Paisley Environmental Project, which started in October 2016, is the largest of its kind that Scottish Water has ever made in Renfrewshire. The project is part of the company’s £250m, six-year programme of work, launched in 2013, to improve river water quality and the natural environment and tackle flooding across the Greater […]

Station Road (Queensbury) Sewer Flooding (2018)

Mott MacDonald Bentley (MMB) carried out an investigation for Yorkshire Water Services into the flooding of five properties in Queensbury in West Yorkshire during periods of heavy rainfall. The investigation concluded that the combined sewer system in the residential cul-de-sac had insufficient capacity during a 1 in 10-year storm return event, resulting in overland flow […]