Essex Rivers Hub

River Chelmer - Great Easton to River Can Pressures

The table below shows the current pressures that this waterbody faces and the solutions that could be put in place to solve these problems. You can learn more about some of these pressures and solutions on the Environment Agency Catchment Data Explorer or you can contact us to find out more.

PRESSURES

SOLUTIONS

Signal Crayfish have been most recently recorded on this water body in 2010. Signal Crayfish cause changes to the natural bankside habitat and also out compete our native crayfish. They are fierce predators and can completely change fish and invertebrate communities so that they are no longer in their natural state.

There is currently no known solution to the invasion of Signal Crayfish, regular monitoring is needed to ensure a strategic approach when a solution has been identified.

Giant Hogweed has been most recently recorded on this water body in 2014. This plant has been in the news a lot more recently due to the horrific burns that its sap can give the skin. This invasive plant is so large that it is able to shade out other native plants.

Giant Hogweed MUST be removed by a professional ONLY. The plant is sprayed off and then removed in a safe manner. If this plant has already been removed from this waterbody then please let us know, if it is spreading further then get in touch.

American Mink have been most recently recorded on this water body in 2009. American Mink cause a wide range of problems on a river, including playing a large part in the local extinction of many natural species such as water voles and kingfishers.

In order to eradicate mink, they must be trapped and dispatched. Trapping must be done catchment wide as mink can travel large distances. It is important that there are enough people involved in a trapping project to ensure that the traps can be checked regularly. Monitoring mink, water vole and otter presence on your river can also help us when planning eradication programmes.

Fish populations have decreased since 2009 which means that this water body is failing for fish. Specific reasons for this have not been identified although the low levels of dissolved oxygen and redundant structures (preventing fish migration) are likely to be contributing to the reduced populations.

Redundant structures should be removed.

In channel vegetation and habitat should be increased to allow improved habitat for fish.

This water body has developed problems with phosphate, and dissolved oxygen levels which both contribute to its overall rating as moderate. Unfortunately there is no data to suggest where these problems are originating from, although point source from local sewage treatment works is suspected. Reduced oxygen levels are often common in summer months because of reduced river flows, higher water temperatures, increased oxygen demand due to increased biological activity and higher effluent proportions in watercourses.

Carry out further investigation in order to determine the source of pollutants and take the action required to solve the problem.

This water body has developed problems with phosphate, and dissolved oxygen levels which both contribute to its overall rating as moderate. Unfortunately there is no data to suggest where these problems are originating from, although diffuse agricultural pollution is suspected. Reduced oxygen levels are often common in summer months because of reduced river flows, higher water temperatures, increased oxygen demand due to increased biological activity and higher effluent proportions in watercourses.

Carry out further investigation in order to determine the source of pollutants and take the action required to solve the problem.

  

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