United Utilities (UU) owns approximately 70 hectares of land along the upper reaches of the River Ehen in Ennerdale. The land is managed in partnership with Natural England and the Environment Agency and also falls within the remit of the Wild Ennerdale Partnership.

The management aim of the land is to provide a healthy natural environment that supports the sustainable recruitment of the freshwater mussel (Margaritifera margaritifera) and Atlantic salmon (Salmo salar) in the River Ehen.

Freshwater mussels are declining rapidly internationally and are listed as critically endangered, equivalent to the risk of extinction of the Orang-utan and Gorilla. In the last 90 years, they have declined globally by 62% and by 87% in Europe; the importance of the River Ehen mussel population can therefore not be overstated.

The River Ehen in West Cumbria supports the largest population of mussels in England and as a result it is designated as a Special Area of Conservation (SAC) and Site of Special Scientific Interest (SSSI). Atlantic salmon is also a qualifying feature of the SAC. The SSSI has been assessed by Natural England as being in “unfavourable declining” condition due to insufficient freshwater mussel recruitment, making the current population unsustainable. Some juvenile mussels are present, but the current demography of the population is not likely to support long-term sustainability. Assessment of Atlantic salmon egg deposition in the River Ehen by the Environment Agenc (2018) indicates that the salmon stock is “probably at risk” and is likely to continue to be for the next five years. Some of the reasons for the decline of both species include habitat degradation from nutrient run-off, excess silt covering the riverbed and an unfavourable flow regime.

To ensure that the River Ehen is a healthy river system, the land surrounding it must be managed sensitively to minimise inputs of sediment and nutrients, which can damage this sensitive habitat and the species that live within it. A low-intensity land management approach is being delivered, with support from West Cumbria Rivers Trust, through a package of work known as the “Compensatory Measures” project. In line with Wild Ennerdale aspirations for the wider valley, the intention is to restore natural ecosystem processes, which means supporting nature to provide functioning water and mineral cycles, increased species diversity, and maximising the use of the sun’s energy to drive all these processes, locking up carbon in healthy soils.

These processes are essential for rich, healthy and functioning land but often get broken down where there is intensive land management and this as a result can lead to sediment and nutrients entering the river. The compensatory measures project is an opportunity to help restore these natural processes and some initial physical works will be required to achieve this. Works will include: the installation of natural willow leaky dams to capture silt and nutrient run-off; encouraging natural regeneration of scrub and woodland to help restore healthy complex soils; planting of appropriate native trees to help the water cycle recover by allowing more water to infiltrate the soil rather than run-off the land, trees also provide added habitat and food for lots of species; and the removal of redundant infrastructure such as broken down riverside fencing to prevent it falling into the river damaging the habitat and causing blockages. This low-intensity management also means that the land will not be used for food or timber production and as such, no additional nutrient application or grazing will be required.

The compensatory measures package is a legal agreement between United Utilities, Natural England and The Environment Agency and has been agreed by Defra.The package must be ‘over and above’ what can be delivered through other schemes e.g. agri-environment schemes.

The Wild Ennerdale partnership is delivering some of the management needed (working with a dedicated River Ehen Project Officer) and using its experience in low intensity land management and its volunteer group to sensitively manage these parts of the Ehen catchment.


Wild Ennerdale Stewardship Plan:



Name Type Size
Wild Ennerdale Ownership Map pdf 378.48 KB
286 B