Why Sign In? Subscribers, sign in to access exclusive content. Unlimited Members, sign in to enjoy sitewide access.
Home / News & Reviews / News Wire / Broken rail likely cause of 2020 UP derailment, fire, bridge collapse in Tempe, Ariz.
Report from NTSB says damage was made worse by lack of inner guard rail on bridge approach
Report from NTSB says damage was made worse by lack of inner guard rail on bridge approach
Get the newest photos, videos, stories and more.
TEMPE, Ariz. — A broken rail is the probable cause of a derailment of a Union Pacific train on a Tempe bridge in July 2020, which led to a fire, collapse of part of the bridge, and a release of hazardous material, according to a report released Thursday by the National Transportation Safety Board.
The severity of the accident reflected the lack of an inner guard rail on the wooden bridge, which allowed the equipment to move laterally into the steel bridge, causing the partial collapse, according to the report.
The broken rail was on a wooden trestle approach to the steel bridge over Temple Town Lake, and led to the derailment of 12 cars of the three-locomotive, 97-car train shortly after 6 a.m. on July 29, 2020. The train was moving at 23 mph at the time of the derailment. jOne of the derailed cars hit the bridge structure, leading a collapse of part of the bridge and sending railcars and the bridge onto Rio Salado Parkway below [see “No estimate for repair of UP bridge …,” Trains News Wire, July 30, 2020].
Among the cars which fell from the bridge were two DOT-111 tank cars carrying cyclohexanone, a flammable hazardous material used in the making of nylon; one of those cars leaked about 2,200 gallons of the liquid, but it did not ignite. The fire on the bridge involved flatcars of lumber. One firefighter was treated for smoke inhalation at the scene; there were no other injuries.
Union Pacific estimated overall damage from the accident to be almost $11 million: $10 million for the bridge, $485,000 to railroad equipment, and $435,000 to track and structures. The bridge was closed for about two weeks as a result [see “Union Pacific expects to reopen burned Arizona bridge …,” News Wire, Aug. 6, 2020].
The NTSB investigation found that the track on the bridge had been inspected just two days before the accident, and identified no track defects; examination of the lead locomotive’s front-facing camera showed no apparent anomalies. The investigation also found that an inner guard rail that had existed on the approach to the steel bridge had been removed for previous bridge work and had not been replaced; UP rebuilt the bridge with inner guard rails extending 50 feet to the north and south of the steel structure.
‘Tempe’ Town Lake (not ‘Temple’). I’ve ridden my bicycle under this bridge many times during my annual trek to escape February in Wisconsin. It’s very impressive that UP had trains running again in just two weeks. The precast concrete spans used in the replacement have date stamps going back as far as 2015 (if I recall correctly). No doubt they were gathering dust in a yard somewhere until the urgent need arose.
FRA releases new rule on fatigue management
Athearn HO scale Ford F-850 boom truck
Union Pacific sued over thefts from trains in Los Angeles
Pittsburgh introduces new name, color scheme for transit system
Members enjoy 15% off any purchase in our store. Join Today!
Don't miss this look at the history of America's most influential builder of locomotives.
Ensure a safe, slow approach from others with this railroad-themed logo mask!
Enjoy moving trains in breathtaking scenes across the country, all year long.
Classic Railroad Scenes: Railroads at Work
Get great snapshots of railroading history in Art Peterson’s newest book.
Get updates with the FREE Email Newsletter.