Rock armour upgrades to Hengistbury Head Long Groyne has now been completed, protecting up to 6,000 homes within the Poole and Christchurch Bays.
The works, which began in April 2024, enable the groyne to continue to reduce the risk of coastal erosion over the next 100 years.
The beach around Hengistbury Head Long Groyne is now fully open to the public again, now that the upgrade is complete.
The Long Groyne remains at its original length of approximately 150 metres from the beach line but is 1.5m higher and almost double the width – 30m at its widest point.
This makes it more resilient to projected sea level rise and the increasing number of storm events predicted over the next century.
During construction, the original Long Groyne from 1939 was dismantled and the salvaged material was re-used to form the core of the upgraded Long Groyne.
Nearly 30,000 tonnes of new, highly durable rock was delivered by sea and transported along the beach to site. Each granite rock weighed between 6-10 tonnes and was carefully placed using one of three 110 tonne long-reach excavators.
The works have also seen important benefits for the natural environment. New and improved habitats have been provided around the Hengistbury Head nature reserve; including for the UK’s rarest amphibian, the Natterjack Toad.
In the sea, new habitats have been incorporated to attract and increase the number of species living under the water around the Long Groyne.
Councillor Andy Hadley, Portfolio for Climate Response, Environment and Energy, said:
“We are delighted that the upgrade of the Long Groyne, which plays a significant role in reducing the risks of coastal erosion from the Purbecks to Hurst Spit, has finished ahead of time and within budget.
“I’d like to thank everyone involved in the scheme who has worked so hard to ensure our coastline remains resilient to predicted sea level rise over the next 100 years, while the introduction of enhancements to boost biodiversity is welcomed and will allow marine and wildlife to continue to flourish in the area.
“I’d also like to thank the public for their vigilance and patience during construction. Now that our works have left the beach and safety checks have been made, the beach has returned to its natural beauty.”
Following completion of the Long Groyne works, and while machinery remains available, approximately 8,000 tonnes of the rock delivered to site is being used to adapt and upgrade a further two short groynes near Solent Beach car park. This involves removing 10 old wooden piles from the outer, seaward end of each groyne and replacing them with the same durable rock used on the Long Groyne.
This will ensure they continue to perform their coastal protection role effectively into the future, including protecting the seaward end of the historic Iron Age Double Dykes embankment. It is anticipated these works will finish by end of November 2024 (subject to weather and tides).
