TEMPE, Ariz. — It's been one year since a Union Pacific train derailed on a bridge over Tempe Town Lake, causing the bridge to collapse and erupt in flames. At least two of the derailed cars spilled out hazardous, flammable materials.
But after one year, investigators still don't know what caused the crash.
On the one-year anniversary of the incident, the National Transportation Safety Board released a 1,300-page preliminary report outlining its findings thus far but not yet giving a cause.
On the same day, 12 News obtained new video from Valley Metro showing a new perspective of the incident from light rail cars passing by the scene.
One video shows the derailment happening. Rail cars are seen leaning off the track as they start to pass through over the Tempe bridge, which was built in 1912.
Then, the video shows a spark on the tracks and soon after, the Valley Metro video shows rail cars start to collapse with the bridge.
Another video shows a light rail train going right through the apocalyptic scene as the fallen rail cars and collapsed bridge burst into flames.
According to the preliminary NTSB report, federal investigators have interviewed several Union Pacific employees.
According to interviews with the conductor and engineer on board the train, they were at the front and had already crossed over the bridge. They were beginning to round a corner when the emergency braking system of the train kicked on. They noted it felt smooth. They saw smoke but did not even realize it was coming from the same train they were on because the derailment happened 49 cars back.
Other Union Pacific employees interviewed include those who inspected the bridge just one month prior, on June 26, when another train derailed in the same spot.
Records show a wide gauge caused that derailment.
Additional records indicate there were defects on the track that were scheduled to be fixed after the bridge collapsed.
In all, the incident resulted in $10 million in damage and an additional $500,000 going back to the City of Tempe.
Thankfully, nobody was hurt in the incident. One emergency responder was treated for smoke inhalation but was released from the hospital soon after.
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