Rehabilitating Windermere’s reed beds (Phragmites australis)
Water pollution can come from various sources. Some from a single ‘point source’, like chemical spill, factory or drainage system. Diffuse pollution however is generally dispersed and varied as agriculture, forestry, mining, construction and urban life can cause it. There has been considerable research into mitigation methods of diffuse pollution and it has been found that ‘soft engineering’ approaches, for example wetlands and reed beds have the potential to limit both diffuse and point source pollution and thus effective in improving water quality.
Natural wetlands take many forms including reedbeds, grazing marshes, fens and lowland raised bogs. They are functioning systems that can clean water by a mix of physical and biological mechanisms, including: plant uptake, adsorption, sediment deposition/retention etc.
Although all systems may regulate water quality to some degree, it is the ‘reedbed systems that are seen as having the greatest potential to act as a treatment system’ according to the review of ‘soft engineering’ techniques for on-farm bioremediation of diffuse and point sources of pollution; defra (2005).
Of course many things can effect their ability to clean pollutants, including wetland size, wetland design and the nature, quantity and timing of pollution inputs.
South Cumbria Rivers Trust was the lead partner in the ‘Restore the Shore’ project. The project was one of 19 which fell within the wider Windermere Reflections programme. Windermere Reflections was a 3 year Heritage Lottery funded programme which aimed to increase understanding of environmental issues within Windermere’s Catchment.
Historically, Windermere had substantial beds and swamps of Phragmites australis fringing the majority of the lakes shores and littoral areas. In recent years, these habitats have become threatened through the destructive effects of wave wash from boat bow waves, damage resulting from boat and canoe launching, nutrient enrichment and from grazing (e.g. Canada Geese, ducks and farm animals).
Examples of sites where extensive reed beds have been lost (or almost lost) include;
- Lazy Bay
- Grassholme Island
- Mitchell Wyke Bay
- Borrans Park
- Beeholme Island
The Restore the Shore project had several phases which aimed to deliver the following;
- Produce a current and historic electronic map of the habitat range of Phragmites australis in Windermere.
- Plant young reeds to facilitate a rehabilitation of reed bed and swamp habitats.
- Protect the existing reed beds with fences and wave barriers
We have recently been successful in our bid for reed bed restoration/creation around Windermere, through the United Utilities Catchment Systems Thinking fund (CaST). We will be restoring 800sqm of reed beds over four sites and engaging with the public about water quality. You can find out more information about the project here.