VolkerGround Engineering was contracted to install new sheet pile walls for Reaches One and Two, along the East Bank of the River Arun as part of the Littlehampton Arun East Bank flood risk management scheme.The scheme, completed by parent company VolkerStevin, is a partnership between the Environment Agency, Arun District Council, West Sussex County Council and Littlehampton Harbour Board.
VolkerGround Engineering installed 113 meters of HZ 1180 M king post sections, 23m–26m in length, with intervening AZ 26 steel sheet piles, which now provides a rigid retaining structure from the harbour entrance northwards towards the town.
The new sheet pile wall was installed using crane mounted plant working from the river mouth. The piles were driven into the underlying chalk bedrock using vibratory and impact hammer techniques suspended from 160 tonne capacity cranes located on the existing waterfront area.
One of the most challenging aspects of the project was to provide substantial temporary piling frames into the river from the bankside, in order to ensure the verticality and location of subsequently installed piles. These structures were designed by engineer Tony Gee and Partners on behalf of VolkerGround Engineering.
This £14.5million partnership scheme includes building a new tidal flood wall to protect 2,500 residential properties and businesses against 100 years of projected sea level rise. The project will also improve the walkway along the riverside from the town to the beach. Work to the flood wall will be complemented by design work which will raise the promenade, enhancing the views across the river. Careful planning has also gone into ensuring that the new promenade has wide visual appeal through the use of improved lighting, tree planting and attractive seating areas. The materials have been carefully chosen to preserve the coastal identity of Littlehampton whilst being robust enough to endure the exposed conditions.