Aquacast blocks for intertidal estuary defences at Aldeburgh Golf Club

Founded in 1884, Aldeburgh Golf Club is England’s second oldest maritime heathland course. The River Course, consisting of nine holes, overlooks a wide, sweeping reach of the River Alde, with wonderful views across the marshes. The course was protected from tidal flooding by earth banks, which had settled over the sixty years since they were last raised. In 2013 a tidal surge breached these defences flooding 120 Ha. of fresh water grazing marsh and the golf course on each spring tide. In 2014 a new defence was constructed along a shorter retreated line.

As a consequence of settlement over the last eight years, the new defences had settled by up to 0.5m.

As a result, overtopping was becoming a common occurrence on spring tides leading to parts of the course occasionally becoming unplayable.

Aquacast blocks were chosen as the preferred solution as the engineer (Hawes Associates) designing the maintenance works was keen to reduce the risk of further settlement which would eventually lead to the sinking of the defence walls. Over time defences can sink by up to a metre in this area which would then necessitate further remedial work.

Aquacast blocks provided a realistic option by providing sufficient strength whilst minimising the weight impact.

The alternative was to create earth banks but this has significant weight implications. A one metre run of an earth bank means 16 m3 of earth, weighing approximately 30,000 kgs, would be required. This compares to Aquacast where the weight would be between 300-400 kgs depending on the height of the wall.

Two other factors influenced the decision to choose Aquacast blocks over raising the earth bank, and that was the amount of damage that an earth bank would have created to the natural habitat (by the use of heavy machinery), and the budget for the scheme in the first place.