Around 7300 barrels (870 000 litres) of crude oil have spilled into the Little Rock River near Doon in Lyon County, Iowa, on Friday 23 June 2018. Fourteen of the thirty two tanker trucks that came off the rails are thought to have been breached, releasing their oil into the river; about half of this is thought to have been contained by a seres of booms placed downstream of the derailment site, but the remainder has been lost into the river ecosystem.
Oil tankers in the Little Rock River in Iowa following a train derailment near Doon on 23 June 2018. Tim Hynds/Sioux City Journal/AP
The precise cause of the derailment is unclear, but it occurred after several days of heavy rain which had caused the Little Rock (and several other rivers in Iowa) to burst its banks, making it possible that the tracks had been undermined by flooding, or had had material dumped upon them which had caused the derailment.
Aerial photograph of the scene of the 23 June 2018 Iowa derailment. Sioux County Sheriff's Office/AP.
Trains carrying crude oil have become an increasingly important part of the distribution system in North America as both production of and demand for oil has exceeded the capacity of the pipeline network. There have been a number of incidents involving derailments and oil spills, and concerns about the safety of the trains following an incident in Lac-Megantic, Quebec, in July 2013,when a 72 car oil train derailed and exploded, killing 47 people.
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