The Coastal Squeeze

© Steve Page

How can we protect ourselves without harming wildlife?

There are a steady flow of proposals to upgrade sea defences around our coast. There is currently an application on Portsea Island which is looking to increase the height of the sea wall.

Such investment is timely given the combined effects of relative sea level rise and climate change leading to more extreme events. The priority for sea defences is understandably life and then property, however well-designed coast defences need not harm wildlife. The Portsea Island defences are carefully designed to avoid expanding out into the wetlands of the harbours.

Our coastline is changing. The same sea level rise and extreme weather which prompts sea defences also drives our saltmarshes and mudflats to migrate inland.

There are some places along the coast where this happens naturally such as the Lower Test Nature Reserve. Long term monitoring here has shown us saltmarsh communities are migrating upstream at an average rate of over a metre a month. Within the dynamic habitats of a large nature reserve such change is readily accommodated.

Lower Test by Mark Heighes

Lower Test by Mark Heighes

The problem with sea walls is such migration cannot occur and so intertidal habitats are being squeezed up against sea walls. The international importance of the habitats, and the vast flocks of bird which depend on them, means a solution has to be found to habitat loss through coastal squeeze.

Sharing ideas and solutions

Earlier this month the Wildlife Trust’s planners met with their colleagues in Sussex Wildlife Trust and the RSPB at Medmerry near Selsey in Sussex. It is here the Environment Agency has found a solution to the squeeze. Low lying land, including part of an RSPB nature reserve, has been re-engineered so that a small intertidal harbour is forming.

The new coastline not only provides an answer to coastal squeeze but also greatly improves the coast defences for the community at Selsey.

The engineering works are inspirational. Everything is new and raw but full of promise. Work elsewhere in Britain gives confidence that the newly made marshes will rapidly colonise. Before being re-engineered the land was grazed with cattle and that is to continue.

Now that the heavy work is done the RSPB are looking to cattle and the tides will guide nature in reasserting itself. This philosophy matches our own and it is exhilarating to see change being delivered on such a scale.

The ultimate test of success is what the changes mean for wildlife. A problem on the Hampshire coast is being solved in neighbouring Sussex. Wildlife does not recognise political boundaries nor the organisations who are providing the habitats.

Working in the world of planning is hard and getting harder. Working together across political and organisational boundaries is a refreshingly positive response to an increasingly difficult world.