Maintenance of the Lake
The lake was created between 1768 and 1771 by Lancelot Capability Brown and is classified as a SSSI (Site of Special Scientific Interest) most notably due to its suitability for over-wintering migrating wading birds, it is also very significant in the context of the Capability Brown landscape and the WHS listing. The lake was created by building a dam across the flow of the River Glyme.
We have noticed over the last 10 years a gradual, but accelerating, decline in the condition of the lake, particularly upstream of the Grand Bridge, which is now classified by Natural England as “unfavourable and declining”. This decline has been manifested in the build-up of silt, combined with nutrients and pollutants trapped in the silt resulting from historic practises within the catchment upstream. Our advice is that Queen Pool in particular is in a downwards spiral that nature will not be able to correct alone and that it will continue at an ever increasing rate without human constructive intervention. Failure to address this will ultimately result in harm to the landscape and parts of the lake reverting to wetland.
Statistics about the Lake:
- 70% of the lake upstream of the Grand Bridge has a water depth of 30cm or less (originally approx. 2.1m deep in Queen Pool)
- 75% of the volume of the lake upstream of the Grand Bridge is now silt.
- The lake silt increases by between 1cm and 2cm a year but can increase by as much as 20cm depending on the prevailing conditions.
The solution is a multi-faceted, multi-stakeholder one, primarily involving dredging, improved catchment management, and upgrading the Thames Water sewage plant. The project is planned to take place over the next 5 years, we anticipate dredging will start in 2 to 3 years’ time at a cost estimated to be in the region of £5m.
Estimated project cost: £5,000,000