We’ve started our latest restoration project in Richmond Park, working to enhance the Beverley Brook in partnership with The Royal Parks, The Environment Agency, the Friends of Richmond Park and the Beverley Brook Catchment Partnership.
Richmond Park is well known for its deer and its nationally important terrestrial habitats, e.g. acid grassland. Given this high status you would be forgiven for thinking that the river was also in good shape. However, it’s actually not and its wildlife is relatively impoverished.
About 14% of the length of the Beverley Brook runs through the Richmond Park and so restoring the river through the park, presents an excellent opportunity to make a real difference to the whole river ecosystem.
Why is restoration needed?
The Beverley Brook, like many of London’s rivers, has been heavily modified in the past leaving a highly uniform river channel lacking in habitat diversity. The river channel has been over-widened and in places deepened along most of its length with all natural woody material and instream features being routinely removed from the channel for decades. Due to these reasons there is little variation in flow and depth and subsequently there is little habitat diversity for fish and aquatic invertebrates.
In addition to this the banks are very steep and the river is incised (if you stand on the top of the bank the river is quite a long way down!) and the banks have been subject to increased erosion due to the intense grazing of deer. The deer enjoy eating the succulent river bank plants. This means there is little vegetation left and there are no root structures to hold the soil on the river bank in place and so it washes into the river. You may have seen a sandy bottom on the river bed: this isn’t actually what it’s meant to look like and is a result of the soil washing in and smothering the natural gravels on the river bed. This is a problem for the river ecosystem as many of the plants and animals that would naturally live in the Beverley Brook need the gravelly river bed habitats to survive.
A natural river system has the ability to self-regulate but when it becomes modified, the processes can get out of kilter and we may need to intervene to kick start them again. All of the modifications to the Beverley Brook have left the river with little power, taking away the opportunity for the channel to naturally fix itself with geomorphological processes.
A large river restoration project in the Park has been developed and funded in partnership with the South East Rivers Trust, the Royal Parks, the Friends of Richmond Park, the Environment Agency and the Beverley Brook Catchment Partnership. The aim of this project is to naturalise 600 m of the Beverley Brook through the park using a number of simple restoration techniques. These include:
- Adding Large Woody Material to increase flow variation and provide a greater complexity of habitats for aquatic wildlife.
- Re-profiling the incised and steep banks to enhance marginal habitats.
- Narrowing and remeandering the channel to create a diversity of different flow patterns and produce marginal wetland berms.
- Erecting fencing and river gates to temporarily exclude the deer to allow the banks to stabilise and for vegetation to recover.
- Creating slower flowing areas as refuge for animals during the high flows which are typical of urban rivers such as the Beverley Brook. This is particularly important to help fish establish and not be washed downstream (and possibly right out of the river) in heavy rains.
- Address the contaminated road run-off input into the river from the A3 by creating a siltation pond and wetland to trap and clean the silt from the road.
So it is going to be a busy couple of months on site and we are all excited about the results this project will bring!
You can read more about the project and how Richmond Park access will be affected during works on the Royal Parks website here.