Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, what guidance his Department has issued on using (a) nature-based solutions, (b) salt-marshes and (c) mussel-farming to help reduce pollution in estuaries.

Natural England (NE) has been working with partner organisations such as the Environment Agency (EA) on a range of projects using nature-based solutions to deliver restoration of our estuaries, coasts and inshore marine habitats, including developing guidance for how this could best be undertaken.

The Restoring Meadow, Marsh and Reef (ReMeMaRe) initiative led by the EA has published a range of useful guidance reports and restoration handbooks on restoring saltmarsh, seagrass and native oyster habitats in estuaries and coasts. The reports help explain the wider benefits that these nature-based approaches have both for nature recovery and healthy ecosystems. A recent report sets out our current knowledge on natural estuary and coastal flood management.

These guides are supported by maps showing potential locations for restoration. The guides describe the wider benefits to local communities from restoring these habitats, including helping improve water quality.

NE has also published evidence on where restoration would be possible for some of our most threatened and declining marine habitats through the Marine Restoration Potential (MaRePo) and MaRePo+ projects. In the Solent, we are aware of a project where oysters are being used as a nature-based solution to improve water quality. NE and Defra are part of a project which released 2000 oysters in 2024.

There are some studies overseas that look at the use of mussels to help improve marine water quality although we are not aware of published guidance for UK waters.

Defra published guidanceon how nature-based solutions may reduce flooding and provide the additional benefit of improving water quality.

The EA published guidance on innovative permitting to water companies to enourage them to trial innovative wastewater treatment schemes using nature-based solutions.