Hillblock Technology in Stolford
The coastal community of Stolford has become the first location in the UK to benefit from innovative flood defense technology pioneered in the Netherlands, Royal HaskoningDHV said in its latest release.
The solution to be implemented is known as Hillblock, a type of block revetment, that uses a series of specially-shaped concrete blocks positioned on the seaward side of an embankment.
Team Van Oord, a joint venture partnership between Van Oord, Kier Group, Mackley and Royal HaskoningDHV will be leading the project.
Today, 18 March, the project will be officially opened by the Environment Agency and the Dutch Ambassador Simon Smits.
“Overlooking the Bristol Channel, Stolford has a history of coastal erosion and is prone to flooding. In 1981 high tides overtopped sea defenses and flooded 660 hectares of land including 24 properties. Livestock also died. In 1990, a high tide and storms caused further flooding,” Royal HaskoningDHV said.
There are already coastal defenses between Stolford and Hinkley comprising of rock armor and an embankment wall. These defenses adjoin a shingle ridge that was prone to serious erosion.
Rising sea levels and more extreme weather conditions have made the ridge and embankment increasingly vulnerable to erosion and increased the risk of a breach. Conventional rock armor, also known as rock revement, would have been too costly and visually intrusive. In addition, the transportation of rock armor would have caused excessive disturbance from heavy lorries travelling in narrow lanes to a remote coastal location, Royal HaskoningDHV said.
It was decided that the best solution was a Dutch system known as Hillblock, a type of block revetment, that uses a series of specially-shaped concrete blocks positioned on the seaward side of an embankment. Storm waves flow over the structure and enter a network of cavities between the blocks that absorb wave energy.
Shaped like champagne corks, the blocks are made from high density concrete and held in place by steel piles and concrete kerbs. Although extremely heavy, each block is designed to move slightly, keeping the structure in place through friction.