Why was this project necessary?
Prior to 1955, the river and pond were separate waterbodies. However, in 1955 the river was diverted to flow through Glassmill Pond with the aid of two weirs at the inflow and outflow points. This decision bought with it numerous challenges including flood risk, siltation, and created problems for wildlife, such as limitations on movement. In 2022 works started with the goal to separate the river and pond once more in order to solve these challenges.
Fast forward to today and Thames21, with the support of their partners, have been able to separate the water bodies once more. This collaborative project involved the separation of the mill pond from the main channel with a bund (barrier). The mill pond has now been desilted, allowing newly independent river channel to carry sediment down the river, slowing the rate of siltation on the pond and maintaining its depth for longer.
Miguel Sanabria, River Restoration Officer at Thames21, said: “We are super proud to have worked with our partners to complete this amazing river restoration project. The River Ravensbourne has now been allowed to flow freely. The more natural shape and size of the river channel should also kick-start natural river processes such as sedimentation in the margins and faster flows in the main channel which would help to create clean, spawning gravels.”
Alongside the separation, cobbles and gravel were installed on the riverbed to allow for easier fish movement, thereby creating a pool-riffle sequence. The team also raised the water level in the area surrounding the culvert, reducing the height fish must overcome when swimming upstream. The project has been outlined in Bromley Council’s Open Space Strategy, as part of its Heritage Conservation for the borough.
Belu is proud to support Thames21, with our co-CEO Charlotte Harrington saying: “We’re delighted to have invested in this project in partnership with Thames21. What a fantastic achievement. A great area for the local community to enjoy, as well as a safe home for wildlife. Belu’s purpose is to change the way the world sees water and this transformation of the River Ravensbourne and Glassmill Pond aligns perfectly. We’re excited to have helped make this project a reality.”
We look forward to seeing the final phase of the project. This will focus on planting, adding to diversity of the river features, managing vegetation, and seeding gravel in 2024.