The Chesterfield Canal hit international headlines in 1978. While dredging the bottom of the canal to remove rubbish a maintenance team pulled up a large chain which had a wooden plug attached to it. Later that day, it was noticed that a whirlpool had formed and it became evident that the section of the canal between Whitsunday Pie Lock and Retford Town Lock was losing water. Investigation revealed that the plug was an original engineering feature of the canal, having been installed to allow sections to be drained for future maintenance purposes. The water drained (as designed) harmlessly into the nearby river Idle. The Retford event became a national and international story at the time, and was even recorded in Lloyd's List. However, these plugs were a common feature of English canals built at that time and other instances of sudden drainage (both purposeful and accidental) have since been recorded, including emptying of the Pontcysyllte Aqueduct on the Llangollen canal.