Case study:Arnos Park - Pymmes Brook: Difference between revisions

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|Contact organisation=Environment Agency
|Contact organisation=Environment Agency
|Contact organisation url=www.gov.uk/government/organisations/environment-agency
|Contact organisation url=www.gov.uk/government/organisations/environment-agency
|Partner organisations=River Restoration Centre, London Borough of Enfield, London Wildlife Trust, Environment Agency, Greater London Authority,  
|Partner organisations=River Restoration Centre, London Borough of Enfield, London Wildlife Trust, Environment Agency, Greater London Authority,
|Multi-site=No
|Multi-site=No
|Project summary=To re-establish natural geomorphological features within the Pymmes Brook, including the creation of natural instream features, natural banks, wet berms, potentially wetland scrapes and wet grassland i.e. reconnecting the river with the surrounding habitats, its floodplain.
|Project summary=To re-establish natural geomorphological features within the Pymmes Brook, including the creation of natural instream features, natural banks, wet berms, potentially wetland scrapes and wet grassland i.e. reconnecting the river with the surrounding habitats, its floodplain. The first step would be to carry out a feasibility study of the Pymmes Brook though Arnos Park, including the surrounding landscape, defining the potential habitats which could be create and where. This would also give an idea of the cost and time scales involved. Depending on the outcomes of the feasibility study, a topography study of the area maybe needed if the its decide that wet scrapes and marshy areas should be created, thereby defining the works that would be needed to create these areas. An application has been made to the London Mayors Parks Programme (need to see if this project gets funding from this). Get partners together discuss desires for the park and constraints, design and estimate costs and estimate the finances available to the project.
 
Potential work:
The first step would be to carry out a feasibility study of the Pymmes though Arnos Park, including the surrounding landscape, defining the potential habitats which could be create and where. This would also give an idea of the cost and time scales involved. Depending on the outcomes of the feasibility study, a topography study of the area maybe needed if the its decide that wet scrapes and marshy areas should be created, thereby defining the works that would be needed to create these areas.  


The North East Thames River restoration document highlights this area as having potential for full river restoration. The works should include the removal of all impounding structures and artificial embankments. Once this has been completed there should be a low flow channel created which meanders its way along the natural course of the Pymmes (may not be the current course, decided by a topographical study). Outside, the low flow channel a peak flow course should be created, this should include wet berms and setback flood defences to allow the river to naturally flood. These areas should contain back waters, wet berms, natural erosional cliff faces and wetland scrapes, which would significantly improve the biodiversity value of the area and the amenity value to local residents.  
The North East Thames River restoration document highlights this area as having potential for full river restoration. The works should include the removal of all impounding structures and artificial embankments. Once this has been completed there should be a low flow channel created which meanders its way along the natural course of the Pymmes (may not be the current course, decided by a topographical study). Outside, the low flow channel a peak flow course should be created, this should include wet berms and setback flood defences to allow the river to naturally flood. These areas should contain back waters, wet berms, natural erosional cliff faces and wetland scrapes, which would significantly improve the biodiversity value of the area and the amenity value to local residents.  

Revision as of 08:39, 7 April 2014

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Location: 51° 37' 16.08" N, 0° 8' 8.59" W
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Project overview

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Status Planned
Project web site
Themes Fisheries, Flood risk management, Habitat and biodiversity, Hydromorphology, Social benefits, Urban
Country England
Main contact forename John
Main contact surname Bryden
Main contact user ID
Contact organisation Environment Agency
Contact organisation web site http://www.gov.uk/government/organisations/environment-agency
Partner organisations River Restoration Centre, London Borough of Enfield, London Wildlife Trust, Environment Agency, Greater London Authority
Parent multi-site project
This is a parent project
encompassing the following
projects
No
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Project summary

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To re-establish natural geomorphological features within the Pymmes Brook, including the creation of natural instream features, natural banks, wet berms, potentially wetland scrapes and wet grassland i.e. reconnecting the river with the surrounding habitats, its floodplain. The first step would be to carry out a feasibility study of the Pymmes Brook though Arnos Park, including the surrounding landscape, defining the potential habitats which could be create and where. This would also give an idea of the cost and time scales involved. Depending on the outcomes of the feasibility study, a topography study of the area maybe needed if the its decide that wet scrapes and marshy areas should be created, thereby defining the works that would be needed to create these areas. An application has been made to the London Mayors Parks Programme (need to see if this project gets funding from this). Get partners together discuss desires for the park and constraints, design and estimate costs and estimate the finances available to the project.

The North East Thames River restoration document highlights this area as having potential for full river restoration. The works should include the removal of all impounding structures and artificial embankments. Once this has been completed there should be a low flow channel created which meanders its way along the natural course of the Pymmes (may not be the current course, decided by a topographical study). Outside, the low flow channel a peak flow course should be created, this should include wet berms and setback flood defences to allow the river to naturally flood. These areas should contain back waters, wet berms, natural erosional cliff faces and wetland scrapes, which would significantly improve the biodiversity value of the area and the amenity value to local residents.

The Pymmes Brook is a clay-based river in a high-energy river catchment. Sections of the Pymmes Brook that resemble naturalised river forms exhibit characteristic features of a high-energy system, meanders, small meander cliffs, gravel bars and pool. The river through Arnos Park has been resectioned, constricted, has a concreted lining (in places) and contains a number of weirs which impound and stagnate the water, resulting in extremely poor water quality (GQA class E) as well as a lose of natural morphological features. Arnos Park has been designated as SINC Borough level 2 for it ancient woodland and damp grassland, the pymmes runs through the middle of the park and currently provides little ecological value, while the potential of the river remains huge. A Flood Risk Management project is being investigated for wider benefits and includes potential significant enhancements to this section of river.

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Catchment and subcatchment



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Project background

Reach length directly affected (m) 1000 m1 km <br />100,000 cm <br />
Project started 2008/01/01
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