Heath Lake SSSI restoration
We’re improving the environment at Heath Lake near Crowthorne. Our work is focused on:
- Heath Lake and surrounding areas
- The settlement basin (pond)
- Nearby drainage networks
- New Wokingham Road and connecting surface water systems
All work is carefully planned to protect and enhance this unique ecosystem.
When and where we’ll be working
We started work in December 2025. The main construction work is expected to take place between March 2026 to October 2026.
Project completion including monitoring is expected by December 2027. This monitoring phase is part of our regulatory commitment under WINEP and will not involve significant construction activity.
Due to access constraints on New Wokingham Road, our working hours are Monday to Friday 8am to 6pm. If needed, we may also need to work over the weekend. This will be Saturday and Sunday 9am to 2pm.
What we're doing
Our environmental improvements will focus on three areas.
Installing silt capture units
We'll be installing six 'Downstream Defender' units. They will capture silt, oil and pollutants from road runoff before they reach the lake.
Removing built-up silt
We'll be removing 500–1,000 cubic metres of silt. This will be from Heath Lake, the settlement basin and the surrounding drainage network.
Tree and habitat management
We'll be carrying out a range of selective tree works to:
- Reduce shading
- Minimise leaf litter entering the lake
- Improve conditions for native plants and wildlife
All ecological and tree works have been agreed with Natural England and Wokingham Borough Council.
Project progress and timeline
- Tree works: Complete
- Lake desilting: Completed (March to October 2026 programme; silt drying ongoing)
- Silt defenders (Units 1 - 3): Installed (March to June 2026)
- Silt defenders (Units 4 - 6): May to August 2026
How this may affect you
We’ll do everything we can to minimise disruption. During the main works (March to October 2026), you may notice:
- Traffic management and delays on New Wokingham Road between 29 June and 28 August. You can view roadworks during this time online
- Full road closure between Saturday 11 and Sunday 12 July 8am to 5pm. You can view roadworks during this time online. Diversion routes include:
- Nine Mile Ride to Lower Wokingham Road to Dukes Ride
- Nine Mile Ride to Old Wokingham Road to Dukes Ride
- Increased construction traffic and activity
- Noise from desilting and construction works (kept within standard limits)
- Temporary footpath closures around the lake, with signed alternative routes
Most disruption will occur between March and October 2026. After this, only low-level monitoring visits will take place.
Get in touch
If you have any questions, please call us on 0800 316 9800 or you can email us. Please quote reference: BB01002858. If you need extra support, you can register for Priority Services.
Our delivery partner is M Group (Morrison Water Services). Site teams will wear Thames Water-branded clothing for easy identification.
We’ll keep this page updated with the latest information.