The Haweswater Aqueduct Resilience Programme (HARP) has rapidly become one of the most consequential infrastructure schemes in the UK water sector—technically, financially, and politically. As the first Direct Procurement for Customers (DPC) concession to reach financial close, the £3bn upgrade programme is now widely viewed as the template for how major water infrastructure will be financed and delivered in the coming decades.

A New Model for Water Infrastructure Finance

HARP is the first UK water-sector project to adopt a direct-procurement-for-customers concession model, blending private‑sector delivery with a PPP‑style long‑term framework. The approach allows United Utilities to procure major capital works through a competitively appointed special‑purpose concessionaire—Cascade Infrastructure, a consortium of STRABAG UK, Equitix, and GLIL Infrastructure.

The model is designed to unlock large‑scale investment while protecting customer value, and regulators have already signalled that DPC will be rolled out across the sector for future mega‑projects.

A Critical Upgrade to a Nationally Significant Asset

The Haweswater Aqueduct is one of the UK’s most important water supply systems. Built between 1933 and 1955, the 110km gravity‑fed pipeline carries up to 570 million litres of water per day from the Lake District to 2.5 million people across Cumbria, Lancashire and Greater Manchester—nearly 5% of England’s population.

Following extensive investigations, United Utilities confirmed that all six tunnel sections require replacement to ensure long‑term resilience. Planning permissions across nine applications and seven local authorities have now been secured.

The upgrade includes 50km of new tunnels, with the largest drives located between Huncoat and Bury—one of the most urbanised sections of the route. United Utilities will continue to operate the aqueduct during and after construction.

Construction and Concession Structure

STRABAG has been awarded an eight‑year construction contract, delivering the new tunnel sections using its UK tunnelling capability. The concession, held by Cascade Infrastructure, covers the construction period plus 25 years of operational responsibility, although day‑to‑day aqueduct operations remain with United Utilities.

This hybrid structure ensures long‑term stewardship of the asset while maintaining operational continuity for a system that cannot be taken offline.

A Landmark £2.5bn Financing Package

To support the long‑term concession, HARP required a sophisticated financing structure—one that has drawn significant attention from global institutional investors.

Key features include:

National Wealth Fund First-Loss Protection

A £300m first-loss protection tranche from the UK’s National Wealth Fund acts as an unfunded mezzanine layer, enhancing the credit profile of the senior debt. The structure is comparable to the EIB’s historic project bond credit enhancement facility.

Dual-Tranche Senior Debt

The £2.5bn financing is split into:

•             10‑year bank capex loan, and

•             30‑year institutional debt, comprising both index‑linked and fixed‑rate tranches.

A Deep Bench of Lenders

The breadth of institutional appetite is striking. Funders include:

Allianz, Aviva, Barclays, BBVA, BlackRock, Crédit Agricole CIB, CaixaBank, Canada Life, DZ BANK AG, Erste Group, Helaba, KDB, KfW IPEX‑Bank, L&G Investment Management, M&G, MetLife, NatWest, Norinchukin, New York Life, PIC, PPR, Rothesay, Sabadell, Scottish Widows, Siemens, SMTB, Société Générale, and SunLife.

This level of participation underscores the market’s confidence in the DPC model and in the long‑term stability of regulated water infrastructure.

Advisory Bench

The deal was supported by a wide advisory ecosystem, including BCLP, Marsh, Alvarez & Marsal, AON, Herbert Smith Freehills, Kramer, Ashurst, Walkers, Arcadis, Crédit Agricole, Dalcour MacLaren, Gridlines, Fitch Ratings, and Equitix Management Services.

Sector Context: A Deal Closed Amid Turbulence

The timing of HARP’s financial close is notable. The UK water sector has faced intense scrutiny, with Thames Water dominating headlines. Against this backdrop, HARP’s successful close is seen as a vote of confidence in the sector’s long‑term regulatory framework and its ability to attract global capital.

Regulator Ofwat has been actively promoting the DPC route for major projects, and HARP’s success is expected to accelerate adoption across the industry.

A Blueprint for Future Water Infrastructure

With construction now progressing and financing secured, HARP stands as a landmark for UK infrastructure delivery. It demonstrates:

•             how large‑scale water assets can be renewed without overburdening customer bills,

•             how private capital can be mobilised through structured risk‑sharing, and

•             how the DPC model can reshape the future of water-sector investment.

As the UK faces increasing climate pressures, ageing assets, and rising demand, HARP is more than a single project—it is the prototype for a new generation of water infrastructure programmes.

1. Procurement (Tender) Timeline – DPC Model

• Procurement route: Direct Procurement for Customers (DPC) – first of its kind in UK water
• Client: United Utilities
• Structure: Competitively tendered concession (design–build–finance–maintain)

Key milestones

• Jan 2025 – Preferred bidder announced
• STRABAG–Equitix consortium selected as preferred bidder
• Competitive tender resulted in selection of a CAP (Competitively Appointed Provider) under Ofwat rules, bundling:
• Financing
• Design & construction
• Long-term maintenance (25 years)

This confirms the project was fully tendered and not directly awarded, with private finance competition at its core.

2. Contract Award (Latest Confirmed Position)

Financial close & full award: August 2025

• Winning entity:
  Cascade Infrastructure Ltd
  (STRABAG + Equitix + GLIL Infrastructure)
• Contracting client:
  United Utilities
• Contract scope:
• Finance, design, build, and maintain (DBFM-style concession)
• ~£3bn value
• 9-year construction + 25-year concession
• Lead contractor (delivery):
• STRABAG UK – design & construction lead
• Status:
• Financial close achieved
• Contract fully executed and awarded

3. Tunnelling Scope (Awarded Works)

• Replacement of 6 tunnel sections (~50 km total)
• Works predominantly underground using TBMs
• Construction start: expected 2026

4. Financing (Award Outcome Insight)

• Total financing ~£2.5bn–£3bn
• Includes:
• Commercial bank + institutional tranches
• £300m National Wealth Fund credit enhancement

This confirms the deal reached bankable close, not just award — a key distinction for major tunnelling PPP-style projects.

  5. Key Supply Chain / Advisory Appointments (Post-Award)

• Independent Technical Adviser: Turner & Townsend
• Strong expectation of:
• Regional civils, M&E, and tunnelling subcontract packages
• Significant supply chain engagement during 2025–2026 mobilisation

6. What’s “Latest” (as of now)

• No re-tendering or changes reported since:
• Preferred bidder → Jan 2025
• Financial close & award → Aug 2025
• Current phase:
• Pre-construction / mobilisation (2025–2026)
  Main works starting 2026

Key Takeaways for tunnelbuilder readers:-

• ✔ Fully awarded – no outstanding main contract tenders
• ✔ One of the largest tunnelling pipelines in UK water (~50 km)
• ✔ Procurement model (DPC) likely to be replicated across AMP8/AMP9
• ✔ Big opportunity now sits in supply chain packages, not top-tier contract

If you would like further information please contact sam@tunnelbuilder.com