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Project

Exceptional performance on Thames Water’s Mains Renewal Framework

Location:

Greater London and the Thames Valley

Client:

Thames Water

Contract value:

£25.9 million

Scope of works:

Clean Water Mains Renewal

Delivering a resilient water network for Greater London and the Thames Valley

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Project Overview

Browne was appointed by Thames Water to deliver the £52.9 million Tranche 0 and Batch 4B Mains Renewal Programme, replacing over 41km of aging cast iron mains with HDPE pipes across Greater London and the Thames Valley.

Part of Thames Water’s wider Mains Renewal Programme, the project improves network resilience and reduces leakage. Upgrading the infrastructure lowers the risk of bursts and service disruptions, ensuring a reliable supply. Careful planning and collaboration were key to minimising disruption in the urban environment.

Key Achievements

0 km

of mains replaced, strengthening the resilience of the water network

0 +

days of road occupation saved through efficient project planning

400+ 0

days of road occupation and potential customer disruption mitigated through efficient project planning

Key Challenges & Solutions

Urban Delivery Challenges

Working in high-traffic areas, we coordinated with local authorities, TfL, and utility providers to manage limited space, underground services, and maintain public access while minimising disruption.

Community Engagement

Affecting over 100,000 people, our team used proactive communication, letters, SMS, and emails to keep stakeholders informed, resulting in no written complaints for seven months.

Efficient Road Use

By sequencing works and refining methods, we reduced road occupation by over 400 days, minimising disruption to customers, businesses and commuters.

Key Outcomes

  • Through a combination of technical expertise, early engagement and efficient delivery, Browne continues to support Thames Water in achieving its long-term network goals — delivering multiple projects each year to a consistently high standard of safety, quality and service.
  • These upgrades contribute directly to Thames Water’s 20.4% leakage reduction target by 2025 and strengthen the resilience of critical infrastructure.
  • The work we have done on this programme epitomises Browne’s proven capability in delivering complex urban infrastructure improvements at scale, with a focus on delivering on time or ahead of schedule.

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