10 tonne first reef section is concertinaed

After days of waiting patiently for the high winds to drop, and despite blustery winds and miserable weather, ASR Ltd completed a highly visual part of the land-based reef construction process yesterday (5th August). Huge cranes folded the first section of the reef, measuring approx 50m by 40m, which makes up one fifth of the total volume, several times into a concertina. This was to enable ASR Ltd to move the reef section onto a barge. The reef section which normally weighs approximately 5 tonnes and makes up a third of the base layer of the reef, weighed 10 tonnes after getting water-logged after heavy rainfall.

What happened yesterday?
Shackles and extra straps were added to each third of the reef section.

Two giant cranes lifted two 30m spreader beams. Each beam weighed 3 tonnes.

The straps attached to the reef section were then attached to various points of the spreader bars.

The cranes then lifted the first third of the reef section and folded it.

A second lot of straps, along the next third of the reef section were then attached to the spreader bars and the reef section lifted. This process was repeated until the reef was concertinaed up. The cranes then moved the reef section onto the barge. When weather conditions are absolutely flat and perfect (there is no swell or wind), the barge will be brought to Boscombe.

The reef was concertinaed up to enable one end of the reef to be attached to anchors on Boscombe seabed. The barge will then be pulled out from under the reef, so that the section lays on the sea’s surface. It will then sink and be pulled taut into place with accuracy.

Meanwhile, what’s going on in Boscombe?
Sand is being refined before it will be pumped at high-speed into the bags. This has been collated into a huge mound. The 260 metre-long flexible pipe used to pipe sand from Boscombe beach out to the reef section when it is in place is being bolted together. Pumping and diving machinery is being prepared.

It will take up to 4 hours to fill each bag. 55 bags in total will make up the entire reef.

Information, videos and updates on the surf reef construction can be found at www.bournemouth.co.uk