A MAJOR project is being planned to protect a massive employment site along the Severn Estuary from flooding and unlock its economic potential.

Proposals for the 1,800-hectare Avonmouth Severnside Enterprise Area include new flood defence walls and embankments, as well as the creation of new grassland habitats for migrating birds.

The work will stretch from the mouth of the River Avon to Aust cliffs.

A joint application from South Gloucestershire Council, Bristol City Council and the Environment Agency says: “The scheme is a key project for ensuring that the Avonmouth Severnside Enterprise Area can reach its full economic potential and protect existing communities by reducing flood risk in the area.

“Further development will ensure that the area expands its role as an internationally significant industrial location, able to attract business investment and provide increased employment for the local and wider population.

“While the area is currently protected from flooding by formal and informal flood defences as well as surface water drainage infrastructure, the ongoing development of the Avonmouth Severnside Enterprise Area is dependent on the improvement of tidal flood defences along the Severn Estuary and effective drainage of surface water from the development area.

“The proposed works to the tidal flood defences will lower flood risk to people, property, existing infrastructure and development land within the area.

“In addition, a key planning requirement for allowing further development within the Avonmouth Severnside Enterprise Area is the provision of mitigatory bird freshwater habitat, necessary to address the projected environmental impacts created by new industrial facilities that will be constructed in the coming years.”

The existing flood defences are sub-standard and do not meet Environment Agency recommendations.

The proposals include new flood defence walls, embankments and flood gates, improvements to existing defences to protect the area from a one in 200-year flood.

A 42-hectare seasonal wetland habitat will be created at Northwick and there will be another covering 97 hectares at Hallen Marsh.

There will also be 14.5 hectares of permanent open water in the form of ponds. 

The plans say: “These habitats will attract important bird species, including gadwall, teal, mallard, shoveller, pochard, tufted duck, lapwing, curlew and common snipe.

“Creating this amount of appropriate new habitat will enable the Avonmouth Severnside Enterprise Area to fulfil its economic potential without impacting the internationally recognised wildlife of the Severn Estuary.”

The measures will trap rainwater but are being designed to ensure they do not increase the flood risk to homes, businesses or other infrastructure. 

The site sits partly in the green belt but the proposals say the defences will be sympathetic to the setting and the new habitats will “enrich biodiversity and landscape character and protect these areas from potential future development or deep plough agriculture”.

The application says: “Although the scheme will change the landscape in this area and will reduce visibility of the Severn Estuary and the foreshore, it will help to improve access, and retained and raised views from other locations on top of the new defences.”

The schemes cross the boundary of South Gloucestershire Council and Bristol City Council so applications will be considered by both authorities.