SIOUX CITY | BNSF Railway has more than doubled the number of big oil trains it sends through Sioux City.
An estimated 20-30 trains hauling at least 1 million gallons of Bakken crude oil are now passing through Iowa's fourth largest city each week, up from around a dozen in mid-February, according to a report the Journal obtained from the Iowa Homeland Security and Emergency Management Department.
That's the largest number since the U.S. Department of Transportation in May ordered railroads to provide states with regular county-specific estimates about the number of trains with 1 million gallons of crude or more. About 35 tank cars are required to haul that much, but many trains haul far more cars.
The new disclosure raises fears about a possible derailment of trains carrying the highly volatile material. The increase in traffic also raises the potential for more frequent waits for local motorists at rail crossings.
BNSF, which is owned by Omaha-based Berkshire Hathaway Inc., hauls much of the oil extracted from the Bakken shale formation in western North Dakota and eastern Montana.
From South Dakota's Minnehaha County, the BNSF oil trains enter Northwest Iowa in Lyon County and head south through Sioux, Plymouth and Woodbury counties. In the Sioux City limits, the track runs roughly parallel to Lewis Boulevard. The oil trains run through the mid-city rail yards before crossing the Missouri River into Nebraska.
At South Sioux City, the BNSF route continues south through Dakota and Thurston counties, according to the Nebraska Emergency Management Agency. At Ashland, most of the trains carrying oil through the state head east through Cass County and back across the Missouri River into Iowa, the NEMA said. From there, the crude continues south to refineries.
The number of big oil trains moving through the region has grown sharply in the past year. In the first state report in July, BNSF estimated three trains per week in the four Northwest Iowa counties.
The disclosure of volatile crude moving through the region has environmentalists and others worried about the potential environmental impact that train derailments and the spills and fires that result from them could have. Derailments of big oil trains in several states in recent years have led to fires and explosions.
Local officials said Friday they are monitoring the latest increase in BNSF trains moving through the city. Gary Brown, Woodbury County emergency services director, said the trains run at much slower speeds through the city, compared to the countryside.
Brown said BNSF and other rail carriers continue to look to improve the safety of the shipments, through increased maintenance of the tracks and reinforcement of the tank cars.
BNSF said Monday it has added safety measures for crude oil shipments because of four recent high-profile derailments in the U.S. and Canada.
Like other rail carriers, BNSF does not comment on traffic volume, routes and customers' cargo.
The Lincoln Journal Star's Richard Piersol contributed to this report.