The River Ash in Ashford has been re-naturalised for the benefit of wildlife and people, learn more here about how these improvements are bedding in.
The Colne Valley Regional Park has worked with Spelthorne Council, The Environment Agency and Spelthorne Natural History Society to successfully re-naturalise the River Ash adjacent to Bronzefield Prison in Ashford. The project was designed and constructed by Five Rivers, a specialist river restoration contractor, in October 2020 which was the wettest October on record.
The project has enhanced over 0.5km of the river’s habitat for a range of aquatic wildlife, transforming the site to provide new habitats for fish, amphibians, invertebrates and waterfowl to thrive. Additionally, the River Ash was poorly connected to its natural floodplain which prevented it from expanding naturally at times when water levels rose. To reconnect the river and to restore some of the natural functions of the floodplain, we have installed two backwaters and a series of offline ponds.
A recently installed backwater, an important recruitment habitat and refuge for wetland species.
We have regularly visited the site following the completion of the project and have observed some surprising changes that we have been working with Spelthorne Council staff to address. Most notably, the pond to the south west of the HMP Bronzefield has continually dropped in level, to the extent that it almost dried out completely. The pond is fed via a pumped pipe and receives water arising from the HMP Bronzefield site. The pump had accidentally been turned off by the prison, meaning that the pond’s inlet was cut off, resulting in the wetland drying out. This also coincided with anti-social behaviour occurring, where the reeds surrounding the pond were set on fire in an act of vandalism. Fortunately, in collaboration with Spelthorne Council, the prison was contacted and issue has been identified. The council and will continue to resolve this issue with the prison so inflow of water to the pond can be restored. We will continue to support Spelthorne Council in monitoring this issue, to ensure the pond recovers and the same issues do not reoccur.
The issue with the pond also coincides with high water levels on the floodplain to the south of the River Ash. The enhancement works completed in 2020 involved reconnecting the river to its floodplain via the creation of a series of ponds and backwaters, which all functioned efficiently at the time the project was completed. It is unusual that high water levels have persisted at the site following a reduction in rainfall and river levels. We are currently trying to deduce whether this issue is related to HMP Bronzefield’s pump being shut off, which may have resulted in the water destined for the pond pooling elsewhere on site. We will monitor the floodplain to see if water levels reduce following the reinstatement of the pump and will continue to provide updates as this issue is addressed.
The other river improvement works completed on site are unaffected and the enhancements to the river channel have established well, helping to create a naturally flowing river system with a range of flow types and water depths, providing great habitat for coarse fish, river flies and aquatic plant species. The areas disturbed by the construction of the project are also starting to become green with spring vegetation and with the fence line removed from the banks of the Ash, the river has now become a focal feature of the site.
On Sunday 16th May 2021 we will be hosting a volunteer planting day to install marginal plants and create dead hedges around the ponds and backwaters to reduce footfall to these features and help the backwater and ponds establish further. If you are interested in joining us to help enhance the site further, please contact [email protected]
Berm and gravel riffle installation re-naturalising the rivers while also providing a range of flow types and water depths .
This is part of the River Enhancement Project, just one of the 19 projects that form the Lottery Landscape Project funded by the National Lottery Heritage Fund.
