During a February thaw in 1831, an ice jam formed on the Clyde and wiped out 40 ships at the Broomielaw Bridge, killing several people and caused major floods, After the disaster the town widened the river significantly.
The 1831 flood caused the Clyde to rise 18ft (5.5m) above the normal high tide level. An earlier flood in 1782 peaked at just over 20ft (6.1m) above normal!
Maps from NLS Maps site (from 1807 and 1857).
