Proposed new reservoir in Oxfordshire

We're proposing a new reservoir in Oxfordshire. The reservoir will help protect public water supplies during periods of drought.

The new reservoir would be filled with water from the River Thames in winter, when there’s plenty of water. We'll release water if river levels drop or demand for water increases.

Reservoirs are valuable because they provide a reliable source of water. They can also offer recreational opportunities, support wildlife habitats, and manage flooding.

Project update

We’ve launched a statutory public consultation on our reservoir proposals. This is a major milestone and your opportunity to:

• View our proposals and consultation materials
• Provide feedback
• Help shape the future of water in your area

The consultation runs from 28 October 2025 until 11:59pm on 13 January 2026. You can find more information on the consultation and upcoming events on our website.

Our indicative master plan

An illustration of our proposed new reservoir.

Map key

1. Reservoir
2. River Thames intake / outfall structures
3. River tunnel
4. Tunnel shaft
5. Pumping station
6. Reservoir tunnels and towers
7. Southern Water - Water treatment works
8. Watercourse diversions
9. Main access road
10. Stevenson to East Hanney road realignment
11. Location of temporary rail sidings for construction
12. Car parks
13. Visitor centre 
14. Café on the crest
15. Water sports centre
16. Nature education centre
17. Recreational lakes
18. Crest walkway
19. Floating islands
20. Lagoons
21. Woodlands
22. Project priority areas for biodiversity
23. Water channel 
24. Replacement solar farm
25. Floating solar

Gate 3