Kenwith Valley flood scheme
Updated 22 January 2025
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Background
More than 250 properties were flooded along Kenwith Stream, with flood depths reaching 1.5 metres in some locations in 1979. This led to the construction of the Kenwith Flood Storage Reservoir by Torridge District Council in 1983, as part of the flood defence scheme. This was adopted by the National Rivers Authority (now Environment Agency) in 1989.
The reservoir overtopped in June 1993, following 26 hours of heavy rain and high tides. This flooded a significant number of residential properties in Bideford. The scheme was then reviewed and improved by raising the reservoir embankment to create more storage capacity.
Reservoir inspections
Under the Reservoirs Act of 1975, reservoirs above 25,000m3 capacity undergo a statutory 10-year inspection. The purpose of the inspection is to identify any requirements needed to maintain and improve the resilience of the structure. The latest inspection resulted in 7 mandatory and 5 non-mandatory requirements which the Environment Agency will deliver. These actions are being delivered under one project, split into three phases.
Latest news
A section of path along the crest of the dam will be closed from 18 November 2024 to March 2025 to enable crest widening and edging kerbs works to the dam. These works will better define the crest access track and make it easier and safer to maintain in the future.
The red area will be closed for about four weeks, followed by the yellow section for about nine weeks. Only one area will be closed at any time. The blue area shows an alternative footpath to bypass the works.
Credit: Google, Imagery @2025 Airbus, Maxar Technologies, Map data @2025
These dates are estimated and are liable to change. Alternative access points to the valley park will not be affected.
Phase 1: 2021 – 2023
Completed in 2023, phase 1 included culvert joint replacement, site investigations and crest extension works. These investigations fed into phase 2 works.
Phase 2: 2024 - 2026
This phase involves the design and construction of improvement measures to the inlet structure, site drainage and dam controls as well as maintenance around the reservoir structures.
Some preparation work is needed in autumn 2024, including:
- Tree and vegetation clearance
- Site compound set up
- Widening site access point on Northam Road
- Creating a storage area for materials
During phase 2 construction:
We may need to restrict parking on Northam Road throughout the construction works to allow access to the site. Access to houses will be permitted.
We propose temporarily closing Northam Road for 3 months in spring 2026 while the new culvert works are underway.
- Red line: Potential closure section on Northam Road (Spring 2026). Access to First Raleigh and Marsh Farm will be maintained.
- Blue line: Diversion route during road closure
- Orange line: Proposed no parking section throughout the construction works: Summer 2024 to Spring 2027.
Phase 3: 2026 - TBC
The final phase will include an appraisal of options and outline design for the secondary storage area. Further details to follow.
Ecological considerations and mitigation measures
Measures have been taken to ensure the protection of the wildlife in the working areas.
Ecological surveys have been carried out of the nature reserve area, both up and downstream of the dam. This has identified the potential for dormice, bats and otters at the site. The mandatory maintenance works will be carried out under a precautionary method of working, following relevant guidance to carry these works out at the most appropriate time of year.
Further surveys will be carried out prior to the works to identify the presence of these and other species, with our contractors working under the guidance of ecologists and the agreed precautionary methods of working.
Mitigation measures:
- Installation of new artificial otter holt away from the works areas.
- Where trees are removed, it is the Environment Agency’s policy to replace 5 for every 1 removed to ensure these establish. Replacement planting will be on site where possible or at a nearby offsite location.
- The project has an aim for 10% biodiversity net gain. To achieve this, we are working with our consultants and Torridge District Council to help develop an environmental management plan for the future of the site to help improve the biodiversity of the nature reserve.
Timeline
- 2021 – S10 Inspection
- Summer 2023 – Phase 1 onsite works
- Winter 2023/24 – Phase appraisal and outline design
- July 2024 – Public information event
- Summer 2024 – Phase 2 compound set up
- Autumn 2024 – Tree and vegetation management
- Autumn 2024 – anticipated start of phase 2 construction
- Winter 2026 – anticipated start of phase 3 construction and potential estuary outfall
- Summer 2027 – anticipated phase 2 completion
- TBC – Phase 3 completion
Please note that all dates on the timeline are subject to change
Once all the phases of works are completed, the compound and storage areas will be removed and the site returned to its previous state. All construction waste will be removed and the work area returned to its normal condition.
The Environment Agency will continue to operate and maintain the flood storage reservoir, working with Torridge District Council to improve the site wherever possible for ecology.
If you have any questions about this scheme, please contact DCISEnquiries@environment-agency.gov.uk.