# Thames Water infrastructure and resource management

> Live situation record from CLSTR: https://clstr.news/situations/thames-water-infrastructure-and-resource-management
> Updated: 2026-08-19T14:00:00.000Z. Sources: 5. Developments: 2.

Thames Water is undertaking various infrastructure projects to manage water resources and services in the United Kingdom. The company has awarded a £150 million contract to Costain for wastewater treatment upgrades across 15 sites in the Thames Valley. This work is part of the Wastewater Asset Assurance Programme, which aims to modernize sewers and sewage treatment works.

Simultaneously, the company faces significant delays regarding a proposed £6.6 billion reservoir near Abingdon, Oxfordshire. Originally intended for completion by 2026, the project is now estimated to be at least 14 years away. The reservoir is designed to address water demand driven by population growth and dry summers, but it faces opposition from the Group Against Reservoir Development (GARD) due to concerns over environmental impact, flood risks, and community disruption.

## Timeline

### 2026-08-19: Thames Water faces delays in building UK reservoir

Thames Water faces ongoing delays in building a £6.6bn reservoir near Abingdon, a project intended to combat water scarcity in South East England amid local opposition.

2 sources. https://clstr.news/cluster/thames-water-faces-delays-in-building-uk-reservoir

### 2026-08-17: Costain awarded £150m Thames Water wastewater upgrade contract

Costain has secured a £150 million contract from Thames Water to upgrade wastewater treatment assets at 15 sites across the Thames Valley between 2025 and 2030.

3 sources. https://clstr.news/cluster/costain-awarded-150m-thames-water-wastewater-upgrade-contract

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Cite as: Thames Water infrastructure and resource management. CLSTR, https://clstr.news/situations/thames-water-infrastructure-and-resource-management