18.Anyway, after Simon has finished prepping the seabed, those caissons are transported over by tugboat and lowered, starting at the south side of the island.
19.Across all three sites, when it came to lowering the caissons, hydraulic dampers in each corner helped to absorb the force of these massive structures hitting the seabed.
20.The way the gates work may be clever, but it's the enormous housings, or caissons, that are perhaps most impressive from a construction point of view.