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2 years agoopen3

How do we best go about preventing river bank erosion, to deepen rivers and prevent water overheating

3 responses to “Deepening rivers – is it compatible with the Riverwoods approach?

  1. Deepening rivers is not something we want to be associated with Riverwoods.
    These are potentially damaging activities and are regulated by SEPA in Scotland.

  2. The River Woods Science Group has reviewed evidence of how river woods help manage sediment in rivers. We found the following:
    There is a very strong understanding of the natural hydromorphological processes which are involved in reducing coarse sediment delivery and siltation of channels by riparian vegetation which helps to maintain watercourse capacity and reduce flooding. Riparian woodlands can reduce sediment from the main stem and tributaries by adjusting natural rates of erosion on the banks, controlling sediment supply in-channel (log jams) and reducing water energy by increasing bank roughness. For example in a single study in the Upper Wharfe catchment in the Yorkshire Dales National Park, modelling work has shown an 80% reduction in coarse sediment loading from strategically planting 5.2% of the catchment in areas of high risk of slope failure and along source flow pathways . The results indicate that it is possible to achieve significant reductions in sediment yield through source control using woodland measures. Similar reductions have been found in other catchments.

  3. Deepening rivers causes a significant adverse impact on habitat, biodiversity, floodplain connectivity and many other river processes. This activity is associated with historic diversion and straightened of river channels for land gain, and subsequent recurrent need for dredging of the channel to prevent local flooding. Mitigating over-deepened rivers is difficult and requires time and space, a good start is to promote a more active two-stage channel with a more dynamic low flow channel that can increase the specific stream power within the inset floodplain. Large woody material can help developing river features and build up.
    Deepening rivers is not an aim for Riverwoods, rather the opposite, Riverwoods can help reducing the need to dredge channels by storing fine sediments and strategically reduce flood risk in different location within the catchment. Also, Riverwoods is a key component to mitigate those high impact realignment pressures in Scotland as part of wider river restoration projects.

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