South Cumbria Rivers Trust (SCRT) completed an exciting urban Natural Flood Management (NFM) project in the heart of Kendal, South Cumbria in Summer 2020.
We had been scoping and developing the project for over two years, as part of the Environment Agency, DEFRA funded, Cumbria NFM programme. With all permissions in place, practical interventions began in August 2020. The site was been offered by South Lakeland District Council (SLDC), the landowners, as a candidate site for the research, development and demonstration of NFM techniques. The proposals were developed by SCRT and supported by The Friends of Nobles Rest, Environment Agency (EA), SLDC, Catchment Designs Ltd and R.G. Parkins & Partners Ltd.
The Kendal Town View Fields project is a fantastic demonstration site of NFM techniques in a townscape setting. To compliment the work we also plan to deliver interpretation and education activities to show how NFM techniques can deliver multiple benefits, such as restoring natural hydrological processes and biodiversity.
What has been done?
Map of the site
The site is being used to test how effective NFM techniques are in urban areas. We have completed a number of rural NFM works, which you can view here.
The project opened up approx. 90 metres of culverted watercourse running through the site.
Existing culvert at Town View Fields
A meandering stream was created, running into bunded wetland areas with stormwater attenuation capacity. Attenuation capacity refers to the storing of storm water in high flows to allow for the slow release of water through the ground or by other means. In this example, it then reconnects to the culvert downstream.
We also installed two Leaky Dams to demonstrate their design to store and slowly release flood water onto during flood events. Again, we have a number of examples of different Leaky dams we have used in past NFM projects.
Example; Leaky Dam
Finally, conservation grass seed mixes were planted to improve amenity, aesthetic and biodiversity benefits. Friends of Nobles Rest have secured funding for the planting of native tree species on site in the near future that will further improve site biodiversity.
NFM Interventions
- De-culverting and de-commission of the existing stone-walled culvert through the site,
- Creation of a new open channel through the site, with reduced slope in comparison with current culverted reach,
- Creation of bunds and leaky dams using natural materials (earth and timber), to temporarily store and attenuate peak flows from the watercourse during storm events,
- Protection of the new channel bed and banks with erosion control measures,
- Construction of a formal headwall to collect and convey flows back into the existing culvert downstream of the site,
- Construction of an impermeable bund to reduce the likelihood of exceedance flow entering neighbouring land,
- Plant trees and encourage grass land habitats through planting conservation grass seed mixes
These works will serve multiple purposes; restoration of a watercourse, researching the effectiveness of NFM techniques, testing the viability of using NFM techniques in urban areas, reducing the peak flow during targeted storm events and providing a public demonstration of NFM.
Catchment Designs Ltd were the contractors that carried out the works on our behalf.