The Sospan Dau, a specialist dredger, will transport around 30,000 tonnes of shingle from offshore near Littlehampton and spray it onto the shoreline near Sovereign Harbour in a rainbow-like arc.
The replenishment work, worth £1 million, is part of the Pevensey Bay to Eastbourne Coastal Management Scheme and is timed to coincide with high tides over several weeks.
Once deposited, the shingle will be naturally redistributed along the coastline through longshore drift.
Paul Levitt, Environment Agency beach manager at Pevensey Bay, said: “This annual shingle replenishment is essential for maintaining the flood defences that protect our coastal communities.
“By carrying out this work in September, we’re ensuring the beach is in the best possible condition to withstand winter storms and high tides.”
The shingle beach at Pevensey Bay acts as a critical flood barrier, absorbing wave energy and reducing the impact of storm surges—especially during winter, when high tides and storms pose the greatest threat.
Natural coastal processes continuously move shingle along the shore, making regular replenishment necessary to maintain effective protection.
The Pevensey Bay to Eastbourne Coastal Management Scheme is one of the largest flood risk projects in the UK, aiming to protect up to 18,000 properties from coastal flooding and erosion over the next century.
The current phase, launched in June, focuses on managing the 8.5km Pevensey Bay frontage and safeguarding more than 3,000 homes and businesses.
Contractor VolkerStevin is leading the beach operations, including the movement of thousands of tonnes of shingle.
The Sospan Dau, built in 1978, is a trailing suction dredger designed for shallow waters.
It will extract sediment from Owers Bank, about six miles south of Littlehampton, and deliver up to 820 cubic metres of shingle per high tide.
This is equivalent to five and a half double-decker buses.
The full delivery is expected to take two to three weeks, depending on sea conditions.
Residents in flood-risk areas are encouraged to check their flood risk, sign up for free flood warnings, and stay updated via the Environment Agency’s website at gov.uk/check-flood-risk, by calling Floodline on 0345 988 1188, or following @EnvAgencySW on X.
The Environment Agency is also seeking public feedback to help shape the long-term coastal management plan.
Residents can complete the survey to share their views at pevenseyandeastbournecoast.co.uk.
This feedback, combined with insights from Eastbourne Borough Council’s Seafront Strategy Survey, will help develop a 100-year plan starting in 2037 to ensure the coastline remains resilient, sustainable and valued for generations to come.
Nick Gray, flood and coastal risk manager for the Environment Agency in Sussex, said: “Sea levels are projected to rise by more than one metre in southern England over this century, and with more frequent powerful storms also predicted, the risk of increased coastal erosion and flooding is likely.
“Early preparation is key to keeping communities safe.”