SHOSHONE — Stay long enough for coffee at the Manhattan Cafe, and you’ll be greeted with a familiar tune.

It’s not a scheduled performance, but about once every hour, the rolling hum of a locomotive stops traffic.

This railroad routine is a norm for many Shoshone residents. However, in years to come, this historical little town’s railroad — the same railroad that crosses the rest of southern Idaho, including Kuna, Nampa and Caldwell in the Treasure Valley — could find itself in the middle of a debate over increased coal exports to China.

If this issue doesn’t sound familiar, you’re not alone. It’s a conflict that’s not expected to hit towns along the coal’s possible route for several years. But it’s important for many city leaders and commuters to begin discussing the issue now to prepare for increased traffic delays and potential environmental impacts from coal exports.

It starts with six proposed coal export terminals sprinkled along the Oregon and Washington state coasts. The proposed terminals would allow coal companies to ship coal to China, a nation with a hungry appetite for coal and loose environmental regulations regarding the energy source — unlike the United States.

Coal mines in the mountains of Wyoming and Montana would feed the Asian nation. Coal companies could ship the coal by train, which would require going through northern or southern Idaho.

The Union Pacific Railroad goes through Shoshone. Sometimes 40 or more trains a day pass through. At the moment, no coal trains pass through the town, says Aaron Hunt, spokesman for the railroad. If that does change, it won’t be for several years, he says.

But just how many railcars may go through Shoshone once the coal terminals open is still unknown, Hunt says.

“It depends on where they open and what our clients decide to do,” he says. “Everything is kind of up in the air at this point.”

Environmentalists and government officials in the Pacific Northwest have criticized the proposed terminals. The terminals must go through federal and state environmental reviews before they can be built, and the projects are already facing resistance.

Several anti-coal organizations have begun estimating how many railcars could pass through Idaho. According to one report from the Western Organization of Resource Councils, Idaho’s railroads could see as many as 60 cars a day.

In the meantime, city officials are preparing long-term projects to help mitigate current and potential traffic congestion.

On average, 7,560 vehicles pass through Shoshone’s main intersection each day, according to Nathan Jerke, spokesman for the Idaho Transportation Department. The average wait time for vehicles when a train passes through the intersection is close to five minutes.

Other smaller towns may not be as affected as Shoshone. For example, in the Magic Valley, the Union Pacific railroad snakes past Dietrich, Gooding, Bliss and Minidoka but not necessarily through any major intersection.

In Minidoka, the railroad winds along the city limits, says Mayor Becky Ziebach. “If there was an increase in railcars, it really wouldn’t affect us,” she says.

However, the number of railcars passing through Shoshone already has its officials worried, says Mayor David Wendell.

As a bedroom community, the town’s residents rely on the roads around the tracks to commute to Twin Falls or Sun Valley for work or recreation, he says.

For now, Wendell says he’s waiting to learn more about the possible railcar increase.

“If it were to increase, it would greatly slow down traffic and that could be a problem,” Wendell says. “We would also be very concerned of any hazardous materials on the trains going through the town.”

The Idaho Statesman contributed.