Located on England’s North Norfolk coast, the Titchwell Marsh is a key piece of the North Norfolk Coast Special Protection Area (SPA) and Special Area of Conservation (SAC). This coastal wetland ecosystem includes freshwater and brackish habitats and is currently protected from the erosive power of waves by seawalls which are becoming increasingly weakened.
The Titchwell Marsh Coastal Change Project aims to protect vital freshwater habitats from both coastal erosion and sea level rise through managed realignment and seawall reinforcement, and mitigate and compensate for the loss of important brackish habitats.
The eastern coast of England is known to have an abundant amount of birdlife, which makes the environmental pressures of sea-level rise and coastal erosion even more concerning. In fact, much of the coast suffers from what is known as a “coastal squeeze” where sea walls and other infrastructure actually prevent the natural mobility of intertidal habitats. The managed realignment strategy at Titchwell Marsh, including seawall reinforcement and intentional breaching, is a response to this.
Through the project, the existing western wall was strengthened, a new wall was constructed, and a breach was made in one of the walls to connect the brackish marsh to the tidal salt marsh in the east, taking into consideration the flow direction and locations of creeks. The sea walls are expected to protect the freshwater ecosystems for the next half century.
The project was supported by several invaluable stakeholders who pushed for action and were critical in achieving all the necessary permits. These stakeholders include:
- Natural England (the UK government’s statutory nature conservation advisor)
- The Environment Agency (the public body responsible for coastal flood defence)
- Eastern Inshore Fisheries and Conservation Agency (the agency responsible for the management of inshore fisheries)
- The local community members and Titchwell Marsh supporters
Each of the stakeholder institutions participated throughout the duration of the project and to varying degrees. The local community had the opportunity to attend three consultation events held on separate days. Over 150 people attended these events. Additionally, a yearly newsletter was published to keep concerned local residents and visitors informed of the progress.
By creating a breach in the sea wall to connect existing salt marsh creeks, a chain of events can occur that result in significant ecosystem benefits. Seawater is able to enter the brackish marsh and flood it with the tide, turning it into a tidal salt marsh. This new habitat, along with new associated mudflats, is attractive to many coastal bird species, and also serves as a better natural defence against coastal erosion when combined with the sea wall.
However, the loss of brackish marsh can be negative for some species, such as avocet which use the habitat for nesting and breeding. In response to this, additional nesting islands were created in the Titchwell freshwater marshes and new avocet habitats were created at other nearby nature reserves.
A notable side benefit of the project has been the reedbed created in the area excavated for materials for the new sea wall. It is expected that within 10 years of project completion, a full reed bed will have grown in the 2.4ha excavation zone.
Understanding all aspects of the coastal erosion processes impacting Titchwell Marsh led to the design and successful implementation of the most appropriate solution. The decision to include an ecologically strategic breach in the sea wall resulted in several benefits and was an example of working with coastal processes rather than against them.
Time and energy spent involving the local community with consultation and education was also integral to the success of the project. It helped the project gain consent for the various planning requests necessary.
Undertaking construction and excavation work in an environmentally sensitive area is not a quick or easy task. At Titchwell, the wintering and breeding habits of bird species prevented such work from being done for most of the year. Construction was only permitted during August, September and October when disturbance could be minimised. This delayed the overall project and impacted some of the busiest weeks for visitors to the Marsh.