The pontoon bridge is a surprisingly old idea, dating back to at around 1000 BC, when it first saw use in ancient China. Simply put, a deck is laid across a series of boats – or ‘pontoons’ – set up to span a river, hence its alternative names of ‘floating’ or ‘boat’ bridge
A pontoon bridge is particularly useful where no existing bridge stands, or has been destroyed. As such it has been of most use for the military, but clearly it has a role to play in disaster relief when events like earthquakes or flooding have destroyed prior infrastructure, cutting off communities from outside aid.
Quick and economical to erect, pontoon bridges tend to be temporary structures, although there are cases, where crossings are reasonably sheltered from strong winds, when such a bridge makes more sense than a traditional design. Some pontoon bridges have lasted for hundreds of years.