For decades, unless there was a compelling reason to do so, Burlington Northern-Santa Fe Railroad train engineers have avoided blowing their horns as they head through Riverside late at night. 

The densely populated suburban areas around Chicago are designated quiet zones, and with all of the crossings controlled by lights and gates, railroad officials determined long ago that they’d give residents near the tracks a break during the late night hours.

But a month or so ago, the horns started blowing, loud and late. At 3 a.m. and 4 a.m. train horns would wake up residents in Riverside near the tracks, and for a while there seemed to be no explanation.

At first train officials believed that the horns were sounded because right around that time there was a welding crew working on the tracks near Riverside. But after the crew finished up, the horns continued.

But in response to complaints from both residents and Riverside officials, the BNSF launched an investigation and last week reported that the problem was related to a glitch in new federally required train safety technology that uses GPS information to prevent crashes involving trains carrying hazardous materials.

“It’s brand new technology, and these are the kinds of things you uncover,” said Andy Williams, regional director of public affairs for BNSF. “It’s what amounts to a database discrepancy.”

The new technology, called Positive Train Control, is a wireless information network that feeds information to train engineers, from speed limits to the locations of other trains, crossing information and switching information. 

For example, if a train is going too fast, the system will automatically brake the train to slow it down.

If there’s an uncontrolled rail crossing, the system will automatically sound the horn – two long blasts, a short blast and then a long blast through the crossing.

That, it turns out, was the glitch in the system for Riverside.

Village President Ben Sells said BNSF reported to him that Herbert Road appeared in the Positive Train Control database as an uncontrolled pedestrian crossing.

As a result, every time a train nears Herbert Road, the horns automatically sound.

“Positive Train Control is a great idea, but they have to work a couple bugs out of the system, and I feel sorry for the people who live over there getting their ears blown out every night,” said Sells, who met with BNSF officials on Monday. “They told us they’re working on it and that we’re not the only place in the country where it’s happening.”

Since Positive Train Control is overseen by the Federal Railroad Administration, it’s the federal database that needs to be fixed, and that could take some time.

In the meantime, said Williams, train engineers have been instructed to manually override the horns once they begin to sound going through Riverside. In the short term, there may be short blasts heard before engineers can react, they won’t be the full-throated wails of the past month.

“For whatever reason it showed this crossing [as uncontrolled],” Williams said. “Unfortunately it happened to be in that area, which is heavily populated.”