PROJECT

Enriching Elmbridge Meadows

Transforming a section of the Hogsmill River into a space where nature can flourish and which people can enjoy is at the heart of a project in Kingston, run by the South East Rivers Trust and partners.

The Enriching Elmbridge Meadows project will re-naturalise this stretch of the Hogsmill as it passes through the popular green space. The area is enjoyed by nature lovers, dog walkers, families and residents exercising, who all benefit from peace along the riverside in the busy suburbs of London.

Alongside environmental improvements, we will run events such as guided walks, community days, practical volunteering and outdoor education sessions.

Enriching Elmbridge Meadows aims to:

Improve public awareness of the river environment, its wildlife and issues

Promote habitat and species diversity by restoring natural processes

Enhance the visual amenity and landscape character of the area

Remove invasive non-native species so natural ones can flourish

Provide a variety of volunteering and education opportunities for local people to engage with the river

Why does the river need improving?

The Hogsmill River’s industrial past and urban surroundings mean that this globally rare chalk stream has been heavily modified and is generally not in a healthy state. The wider river catchment and its wildlife face a huge range of pressures including pollution, inputs of sewage, low flows, fragmented, poor quality habitat and invasive non-native species. The stretch of river running through Elmbridge Meadows is no exception.

The area is a much treasured space by local residents, including dog walkers, ramblers, riverfly volunteers, schools and other education outlets.

The 1km water channel through the Local Nature Reserve is incredibly straight, over-wide and the banks are incised – steep and deep. The channel characteristics are the same through much of this stretch of river, with little variation in water depth, habitat structure or flow diversity – which is needed for wildlife to flourish.

The man-made steep banks inhibit movements of wildlife between land and water, reducing biodiversity.

The river channel is very straight and has many steep banks

Exciting chance to help wildlife thrive

The Enriching Elmbridge Meadows Project is an exciting opportunity to enhance a significant proportion of the Hogsmill River, bringing benefits for both wildlife and the community alike.

Our methods to improve the river for nature and bring it back to a more natural state will include regrading the steep banks, to create wider and richer marginal habitats.

We will also add woody materials, such as fallen trees or their branches, to create habitats along the banks, where aquatic invertebrates such as fish fry, eels and small mammals can thrive.  This will create variation in the river and provide areas of faster flowing water.

Narrowing the channel and adding wood will also help to cleanse the gravels which are largely buried between sand and silt. This will improve spawning areas for fish.

Other possible improvements include creating a backwater to improve habitat for wildlife and to provide storage for flood water. Meanwhile, adding native plants will help a wider range of wildlife flourish, in and next to the water.

The project is receiving funding in the form of a donation from Thames Water as a Voluntary Reparation after a pollution incident in 2016. A temporary loss of power to the Hogsmill Sewage Treatment Works led to a discharge of 79 million litres of sewage from a manhole onto a neighbouring playing field and subsequently into the river at the Green Lane Recreation Ground. Thames Water was fined £4 million in May 2021.

A uniform riverbed means a limited variety of wildlife can thrive

Tackling balsam in a new way for the area

The South East Rivers Trust, through the Hogsmill Catchment Partnership, is using a new, biological method to tackle Himalayan Balsam throughout Elmbridge Meadows.

Balsam, an invasive non-native species, was brought into the UK from India and Pakistan in the mid-1800s by Victorian plant hunters. Each plant can produce up to 800 seeds per year and it can spread prolifically.

Managing balsam requires a strategic approach. We are introducing a rust fungus to the balsam, which is widespread across the meadows. The biological agent has been devised by the Centre for Agriculture and Bioscience International.

When inspected in September of the same year, there was immediate evidence that the rust fungus had “taken” on the test plot of balsam, indicated by spots appearing on the underside of the leaves.

Further trials will be carried out in 2023. However, volunteers will still be needed for the foreseeable future for balsam bashing events, which will continue to be a major part of controlling this plant.

We have released spores of a virus on a stretch of the Hogsmill to try to tackle the balsam

How can the public learn more and get involved?

During 2023, the South East Rivers Trust will be hosting pop-up stalls in the local area, to engage with the local residents and find out how they enjoy the river and surrounding areas.

After river restoration work – due to take place in 2024 – is completed, interpretation boards will be put up to enhance understanding of the river, the issues it faces and describing the wildlife that visitors should hope to be able to see.

Community volunteering events, such as planting days, will take place to engage local residents with the project, fostering a sense of local stewardship.

The increased range of wildlife and new features in the river will make it an ideal venue for the South East Rivers Trust’s education programme for schools and youth groups.

The South East Rivers Trust regularly engages with communities through pop-up stalls and walks and talks

Thanks to our supporters

Thames Water