This is us coming back up the lift with the trip boat in the other caisson going down, they take two narrow boats each or one wide beam trip boat. They weigh 250 tonnes each which includes 160tonnes of water held in each one. It takes about 10 minutes to travel the 50ft between the Trent & Mersey canal and the River Weaver below.. There is a hydraulic ram for each one that goes into a 50ft shaft driven into the soil beneath the caisson.When the shafts were dug in the 1870s they used compressed air to keep out the river water and many of the workers got the bends.
9 hours ago