The Pevensey Bay Beach Replenishment

ProjectSuffolk Coast South England

Using Soft Engineering Coastal Protection techniques to Hold the Line on a coast under threat.

Coasts : Coastal Protection / Soft Engineering Case-Study – Pevensey Bay 25

Reasons behind the Beach Replenishment scheme at PevenseyReason 1 : Almost all of the 150 wooden Groynes had deteriorated and either needed repair or replacement. Both would be very expensive and use a lot of hardwood – which isn’t a sustainable solution. They were removed in 2007.

Reason 2 : The beach environment has many valuable plant species and these needed to be protected and encouraged to thrive.

Reason 3 : There are many coastal homes looking out over the beach – and their protection, but also their views needed preserving.

Removing the old groynes

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Technique 1 : Beach Replenishment

Sand and gravel is hoovered up by a dredger ship off the coast, and sprayed onto the lower beach at high tide.

At low tide, bulldozers push the material up the beach to raise the height of the beach

This takes place 3 times a year – in early Autumn after the holiday season, in January before the main winter storms, and at Easter just before the holiday season and to correct winter storm damage to the beach.

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Technique 2 : Beach Recycling

There is strong Longshore Drift from West to East along the bay

Bulldozers dig up the accumulated sand at the eastern end of the bay and transfer it to trucks.

Trucks take the beach material back along the beach to the western end – so that Longshore Drift can distribute it along the length of the beach over the year.

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Technique 3 : Beach Re-profiling

This means changing the gradient of the beach to the best one for absorbing the wave energy.

Winter storms remove lots of the lower beach with their strong backwash.

Bulldozers spread the sand evenly across the beach in Spring to create a more even profile – which is better at absorbing wave energy.

Before

Re-profiling

After

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