BOUNDARY COUNTY, Idaho — Wednesday’s train derailment in Boundary County marked at least the third such derailment in the county since the mid-1970s.

Since Wednesday evening, authorities have been working to remove a Burlington Northern Santa Fe engine that derailed and crashed into the Kootenai River roughly 10 miles east of Bonners Ferry.

On Friday, BNSF officially announced that the derailment was caused by a rock slide that blocked the tracks. Two BNSF crew members were aboard a partially submerged engine and subsequently had to be rescued via boat.

The railroad was expecting to remove all but one of the engines from the area by Friday, according to a BNSF spokesman. A timeline to remove the submerged engine had yet to be determined, the company said.

Of at least three previous notable derailments in Boundary County, two have occurred in the last five years.

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According to data from the Federal Railroad Administration, two derailments have taken place on Union Pacific Lines in the county since 1976. 

No one was injured in either of the derailments, one of which was human caused. 

The other derailment was due to “other” causes according to FRA data. Both derailments accounted for roughly $468,000 in damages. 

The agency’s data only accounts for “reportable derailments,” according to an FRA spokesman.

One of the Union Pacific derailments occurred in March 2017 when a train carrying grain derailed due to a mudslide on a line four miles North of Highway 2.

Officials at the time said the train was crossing the slide area when a vibration of the train caused the area to “let go.” Four railcars with grain slid down the hill close to a river and another six to eight cars were on their side within the rail line area. No injuries were immediately reported.

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The FRA data, however, doesn’t appear to account for a May 2014 derailment that occurred on the same BNSF line as Wednesday’s accident.

In that incident, a BNSF freight train derailed near the Kootenai River five miles East of Bonners Ferry. Nothing was spilled into the water and no hazardous materials were involved, according to wire reports. 

Up to 19 cars derailed and some “rock product” spilled. The Bonners Ferry Herald reported at the time that the accident took place less than a week after a smaller derailment on the same stretch of track. A cause of the derailment wasn’t immediately determined at the time.

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