Pontoon bridge unprecedented 730-meter, fortified pontoon bridge across the Scheldt river at the Siege of Antwerp in 1584 to close off water access to the city. In the battle of Saraighat in 1671, the Ahoms spanned the river Brahmaputra at Saraighat over an improviso bridge of boats. In the 1670s, the French devised the copper pontoon; after this point, rivers and canals ceased to present significant obstacles. The early modern period in pontoon use was dominated by the wars of the 18th and 19th centuries during which the art and science of pontoon bridging barely changed. This however did not stop all
Pontoon bridge remain in place much longer. Hobart Bridge, a long pontoon bridge built 1943 in Hobart, was only replaced after 21 years. The fourth Galata Bridge that spans the Golden Horn in Istanbul, Turkey was built in 1912 and operated for 80 years. Provisional and lightweight pontoon bridge are easily damaged. The bridge can be dislodged or inundated when the load limit of the bridge is exceeded. The bridge can be induced to sway or oscillate in a hazardous manner from the swell, from a storm, a flood or a fast moving load. Ice or floating objects (flotsam) can accumulate on