The River Ravensbourne and its tributaries, the River Quaggy, River Pool and Honor Oak Stream (Chudleigh Brook), pass through the heart of the London Borough of Lewisham.
Flooding from the River Ravensbourne has been recorded in the Lewisham and Catford area since 1809. The last major flood was in September 1968 where heavy rainfall caused the river to overtopped the banks, flooding several hundred homes and businesses. Less severe river flooding has also been recorded, including in 1977, 1992 and 1993.
There are approximately 4,000 homes and businesses located within the floodplain of the River Ravensbourne and Honor Oak Stream between Catford, Lewisham and its confluence with the Thames at Deptford. Of those properties identified, 420 homes and 90 businesses are at a ‘high’ or ‘medium’ risk of flood water entering their property.
If the defences aren’t maintained, these figures could increase to approximately 7,500 being within the floodplain, with 990 homes and 240 businesses at a ‘high’ or ‘medium’ risk of flood water entering their property. Climate change is also expected to increase the number of properties at risk.
The Environment Agency is proposing a £17.7million flood alleviation scheme to help manage the risk of flooding to approximately 990 homes. The scheme is being delivered in partnership with Lewisham Council to ensure that the flood alleviation proposals in the eastern half of Beckenham Place Park form part of a joined up plan to rejuvenate the whole of the park. This will create a new space for the community to relax and play amongst nature and local heritage. The scheme is a combination of 3 elements.
Flood storage at Beckenham Place Park
As one of the largest open riverside spaces in the area, the park provides an opportunity to temporarily store water in times of flood, keeping it away from homes and businesses. To do this, the Environment Agency will need to re-landscape the park to the east of the railway line to include raised earth embankments. These would hold water safely within the park for a short period during times of flood.
This work would also provide an opportunity to enhance this side of the park for existing users and new visitors. The park would continue to be public green space, but with more diverse habitat and improved recreational facilities for the local community to enjoy. These attractions will include a new BMX track, an enhanced skatepark, a playground, a refreshment kiosk and improved walking, running and cycling routes.
The plan includes making the river a key focal point on this side of the park, similar to sites such as Sutcliffe Park in Kidbrooke and Ladywell Fields in Ladywell. Opportunities identified include reinstating an historical wetland habitat within part of the park. This could be similar to the successfully recreated wetland at Sutcliffe Park. Other opportunities include new paths and play facilities.
Works on the Honor Oak Stream in Ladywell
Following feedback from public consultation in 2014, the Environment Agency is proposing to temporarily store floodwater at Ladywell Green to reduce the risk of flooding from the Honor Oak Stream/Chudleigh Ditch.
To do this, they would need to lower the park by up to 1.5m and re-landscape it so that it will stay as usable park space. The Environment Agency has updated the concept drawing for the park, using feedback received, particularly the footpath routes.
Localised works to existing river walls
Even with the proposed flood storage at Beckenham Place Park, the Environment Agency’s river investigations have shown that there are 9 low points in the defences downstream which will need to be raised to hold more water within the river channel. Concept drawings are being developed for these sites.
Once the scheme is complete, the Environment Agency will continue to work with local landowners to ensure they are aware of their responsibilities to maintain their part of the river so that water flows freely.
Benefits of the scheme
The Environment Agency estimates that by doing these works and continuing the Environment Agency’s regular maintenance programme, a total of £270 million worth of flood damages could be avoided over the next 50 years. Approximately 990 homes and 240 businesses will benefit from a reduced risk of flooding. More than 6,000 further properties will have a reduced risk of flooding to their gardens and open space. Key community facilities will also benefit, including part of University Hospital Lewisham, Lewisham Police Station, 41 electrical substations, Deptford pumping station, critical roads, the Docklands Light Railway and National Rail lines.
Heritage Lottery funding
The Environment Agency received a grant from the Heritage Lottery Fund which helps the flood alleviation scheme in the eastern half of the park form part of a joined up plan to rejuvenate the whole area.
Having completed an outline design and business case, the Environment Agency are now working on the detailed design. They expect to start construction in 2018, with the scheme being operational by 2020. The detailed design stage will include:
- further engagement with the community, land owners and user groups to seek views
- investigation works on site
- submitting a planning application in 2017
As well as helping to inform the final proposal, these activities may mean the Environment Agency will need to change the estimated start date for construction.
For more information about the Lewisham and Catford flood alleviation scheme, please contact Mike Wilkinson at the Environment Agency on 03708 506 506 or email firstname.lastname@example.org.