Full Breakdown
White Horse Reservoir Plan Aims to Boost South-East Water Supply
By Drooid · · How we work
New Reservoir Proposal
Thames Water intends to submit a planning application for the White Horse Reservoir near Abingdon, Oxfordshire, before the end of the year. The scheme envisions a 150-billion-litre storage facility that would draw water from the River Thames during winter months when flow is high. The reservoir is projected to serve up to 15 million customers across the south-east by 2040.
Project Scope and Funding
The development is estimated to cost between £5.5 billion and £7.5 billion. Funding is expected to come from Thames Water’s capital programme, with the company positioning the reservoir as a long-term answer to regional water scarcity. The plan highlights the need to secure additional water sources as climate variability reduces reliable rainfall.
Water-Harvesting Strategy
According to the proposal, winter inflows from the Thames will fill the reservoir naturally. Because the Thames Valley has recorded only about 35 % of its average rainfall so far this month, the project also explores upstream catchment enhancements to capture extra water. These “natural ways” include land-based storage and managed aquifer recharge, though detailed engineering designs remain pending.
Potential Impact on the South East
If realised, the reservoir could alleviate pressure on existing supply networks, especially during dry spells that have become more frequent. By increasing storage capacity, Thames Water aims to reduce reliance on emergency water restrictions and improve resilience for millions of households and businesses.
Next Steps
Thames Water will seek planning permission by year-end, after which detailed environmental assessments and public consultations are expected. Assuming approval, construction could commence in the early 2020s, with the facility targeted for operational use by 2040.