Background

The Dorset National Landscape Partnership have secured funding in principle for a project across the Brit catchment that will reduce flood risk in Beaminster, Netherbury and Bridport. The purpose of the project is to look at the effectiveness of Natural Flood Management, while also looking to see if we can reduce the management burden on Bridport’s flood defences and enhance nature.

The Natural Flood Management Programme is a Defra project, administered through the Environment Agency. Its aim is to reduce flood risk in high-risk communities, while learning about the effectiveness of natural flood management techniques.

The River Brit project is one of 40 nationally that have received a share of £45 million. You can find out more the gov.uk website. The list includes another Dorset success – a project on the Swan Brook in Purbeck, led by the National Trust.

The Brit Catchment

There has been a focus on managing flooding in the wider Brit catchment in recent years:

  • The Environment Agency operate a flood defence scheme in Bridport. These defences allow river water to be managed in times of high flow. From time to time, they require built-up sediment to be removed, which is an expensive operation.
  • In addition to flood risk from rivers, properties in Beaminster, Netherbury and Bridport are also at risk from surface water runoff, where saturated ground can no longer soak up rainwater, which in turn leads to significant overland flow and flooding.
  • Over the past two years, Dorset National Landscape has been working with the Environment Agency, an independent geomorphologist, and Dorset Wildlife Trust, to identify high-risk fields where runoff could cause problems. We have also been working with landowners to identify opportunities to work with nature to overcome these issues. The aim is to reduce local flooding issues and stop sediment entering the rivers and ending up behind the flood defences in Bridport.
  • Dorset Council’s Flood Risk Management Team and the Farming and Wildlife Advisory Group are also interested in the risk posed by flooding and have been working on a rural runoff project over the past three years, which aims to tackle flooding in high-risk communities.

The funding from the Natural Flood Management Programme will allow us to bring these elements together and allow more efficient delivery.

River Asker (c) Nick Gray

Project details

A partnership of Dorset National Landscape, West Dorset Wilding  and Dorset Wildlife Trust submitted a bid in November 2023. In February 2024, we found out that this bid had been successful, and we will now work towards developing a fully costed programme of works for submission in September 2024. Delivery will take place between October 2024 and March 2027.

Our bid included several methods of natural flood management that will be installed at strategic locations throughout the catchment. A significant element of the project is to monitor the effectiveness of these interventions, so that natural flood management can play an increasing role in managing flood risk into the future.

Our proposal includes a range of solutions:

  1. Four hectares of land use change that will support storage of excess rainfall in the field. This includes reversion of arable and intensively managed grassland to semi-natural grassland and wetlands.
  2. One hectare of in-field flood storage, through the creation of small bunds that will hold back water on high-risk overland flow routes.
  3. 12km of leaky dams to slow the flow of water through the catchment, trapping sediment along the way.
  4. Five hectares of floodplain reconnection, lowering riverbanks to allow more water onto the floodplain, and stored in wetland areas, scrapes, and ponds. This increases storage capacity of flood waters in time of need.

The total value of delivering these solutions is £280,000. Furthermore, £215,000 has been allocated to detailed monitoring and evaluation of the effectiveness of these measures. Staff time to design, secure permissions, and oversee delivery, as well as enable wider community engagement, come to a further £117,000. With a 10% contingency, the overall budget of the project is £673,000.

Natural Flood Management in the Brit Catchment

What next...

We now have to develop the details of the project and present a business case. We have until September 2024 to do this. This will involve more detailed planning with landowners, securing the required permissions and installing monitoring equipment. In September, our case will be reviewed, and we hope to be given the green light to begin delivery in earnest.

Should you have any questions, please contact Ian Rees, Countryside Project Officer.