Jacobs, Kier, MMB, Murphy and VolkerStevin appointed to deliver major AMP8 infrastructure works.

United Utilities has confirmed the delivery teams for the biggest ever overhaul of the Salford sewer network. The £525m programme is the first major step in the £13.7bn Big North West Upgrade and signals a shift toward complex brownfield engineering ahead of the AMP8 regulatory cycle.

An integrated team comprising Jacobs, Kier, Mott MacDonald Bentley (MMB), Murphy and VolkerStevin will spearhead the work. The project aims to modernise wastewater assets across the city over the next five years to slash storm overflows by 60% and tighten environmental performance across the region.

The £13.7bn context: why now?

This project is not an isolated upgrade. It is a critical component of the wider AMP8 (Asset Management Plan 8) cycle, which runs from 2025 to 2030. The industry is under unprecedented pressure from the Environment Act 2021 to eradicate harm from storm overflows and achieve nutrient neutrality in UK waterways.

For the North West, this translates to a massive £13.7bn capital investment plan designed to protect over 500km of rivers and bathing waters. The Salford and Eccles projects are the tip of the spear: high-visibility, high-impact interventions designed to improve water quality in the Salteye Brook and the Manchester Ship Canal.

The project: engineering on a knife-edge

The upgrade targets two flagship sites at Salford and Eccles. Unlike greenfield projects where engineers start with a blank slate, these are highly constrained interventions within a dense urban environment.

Salford Wastewater Treatment Works (£225m)

At Salford Wastewater Treatment Works (£225m), the priority is maintaining operational continuity. The plant cannot simply be switched off. Five existing trickling filters will be demolished to free up land, requiring a phased construction approach that keeps the legacy assets running until the new streams are commissioned.

The site will transition from passive filtration to active BioP ASP (biological phosphorus removal activated sludge plant) technology. This shift is essential to strip out ammonia and phosphorus without heavy reliance on chemical dosing.

However, BioP introduces significant complexity. The bacteria required for the process are temperamental and require precise environmental control. Engineers will also need to navigate deep industrial contamination and potential unexploded ordnance (UXO) from the Second World War, all while managing heavy logistics next to a live railway line and the Manchester Ship Canal.

Eccles Wastewater Treatment Works (£302m)

Eccles Wastewater Treatment Works will see a larger £302m investment. The central feature is a 60,000 cubic metre underground storage tank which is large enough to hold 24 Olympic-sized swimming pools.

Designed to capture excess rainfall and prevent hydraulic overload, this tank is a response to increasingly intense storm events driven by climate change. Constructing such a massive subterranean structure near the M60 motorway presents a major civil engineering challenge.

The works will likely require deep shaft sinking or diaphragm walling techniques to retain the ground in high-water table conditions. Extensive groundwater dewatering and precise temporary works design will be critical to prevent subsidence that could affect the region's transport infrastructure.

The enterprise model: a shift in delivery

Perhaps the most significant change is the commercial model. United Utilities has adopted an enterprise model for delivery which aligns with Project 13 principles.

In traditional contracting, clients would bid out isolated packages of work (e.g. build a tank). In this model, partners are integrated into a single team from day one.

• Jacobs brings digital twin and process design expertise.

• Murphy and Kier offer heavy civil and tunnelling capability.

• MMB provides agile design-and-build experience.

• VolkerStevin adds specialist marine and civil interface knowledge.

This allows for early contractor involvement (ECI), where constructability issues—such as how to move heavy plant machinery across a constrained site—are resolved during the design phase, not during construction.

The talent critical path

The scale of the works comes as the industry faces a documented deficit of 43,700 workers to meet AMP8 targets. The Salford and Eccles projects will create immediate demand for specific technical disciplines:

• MEICA project managers: The interface between new BioP technology and legacy mechanical systems is the highest risk point. Managers who can oversee complex fluid integration and SCADA telemetry upgrades will be essential.

• Process scientists: Commissioning a BioP plant is not a plug and play exercise. It requires scientists who understand sludge kinetics to cultivate and stabilise the biological biomass.

• Civil specialists: Engineers with experience in deep excavations, brownfield remediation, and temporary works design will be heavily recruited to manage the ground risks at Eccles.

For the region's workforce, this investment represents a career-defining opportunity. This is not short-term contract work; it is a five-year programme delivering the environmental backbone of the North West.