Most Important Northbrook Intersection May Be One You Can't Drive Through

They carry commuters. They carry automobiles. They carry interstate vacationers, flammable liquids, chemicals, coal and agricultural products. 

They’re the trains that pass through Northbrook every day—and most cross over a pair of switches known to those responsible for them as “A-20.”

Located just west of the , in southwest Northbrook, the switches lie about 100 yards north of Techny Road, where they’re easy to spot, bookended by a pair of rail signal towers. 

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If you’ve passed by the area before, you may have already seen Metra maintenance crews hovering over them, welding equipment in hand, while one or more of the agency’s white trucks stand nearby, amplifying the radio communications of rail dispatchers. It’s Metra’s responsibility to keep A-20 in working order. 

On a typical weekday, 61 Metra, 16 Amtrak and 20 Canadian Pacific (CP) Rail freight trains pass through Northbrook’s Metra North line tracks, according to Metra spokesperson Michael Gillis. The switches, of course, play a vital role in keeping them going in the right direction. 

If it’s a CP Rail freight, CP dispatchers control the switch in order to lead the trains into or out of the cutoff that connects Metra’s Milwaukee North Line tracks in Northbrook to those of the Union Pacific in Glenview. (The cutoff straddles both Glenview and Northbrook.)

According to CP Rail spokesperson Ed Greenberg, CP freights are usually going to, or headed from, his company’s freight facility in Bensenville. The switches on the opposite end of the cutoff, or the “Shermer interlocking” in railroad parlance, are maintained by Union Pacific crews, while the tracks of the cutoff itself are maintained by CP Rail.  

The frequency with which Metra crews are seen near A-20 reveals the importance of the cutoff to Chicago area rail traffic, and how much maintenance its switches require as nearly 100 trains–and thousands of rail cars–cross every 24 hours. 

Though they are operated remotely now, the switches used to be controlled manually by crews of the Metra’s Milwaukee North Line’s former owners, The Milwaukee Road, whose switching crews worked out of a long-gone tower located nearby (see accompanying photos), according to Gillis. The tower was one of the now-defunct railroad’s “A” towers, which is why the A remains in A-20. In addition to the tower, the Milwaukee Road also once operated a passenger station just north of Techny Road, and south of the switches. The station, along with a Milwaukee Road train bound for Milwaukee (a service now provided by Amtrak), can be seen heading into Northbrook on what are now Metra rails at 0:54 in a clip that appears to date to the 1960s: http://www.youtube.com/watch?v=0w-FS03NUkk&feature=related

According to Greenberg, CP Rail uses an approximately 14-mile stretch of the Milwaukee North line, from Northbrook due north to Roundout, IL. After that, Metra’s tracks continue west to Fox Lake and CP Rail’s tracks continue north. 

CP Rail pays Metra for usage of the tracks.

“In general, products we move for our customers include just about everything residents would use in their daily personal and business lives, ranging from household products and automobiles to fertilizers and lumber,” Greenberg said. Asked what hazardous materials, in particular, the rail line carries, Greenberg said he was not able to disclose specifics for security reasons.

“Regulated commodities make up about five per cent of everything CP moves across the United States and Canada,” he said—and local law enforcement officials are given information on the particulars of any hazardous materials.

Today, a large part of what Metra’s crews do in Northbrook is maintain A-20’s switches. According to welder and local railroad enthusiast Jim Dearborn, such crews give special attention part of each switch called a frog—the point in the switch where the two rails cross.

“It kind of looks like a frog from the right perspective, hence the name,” Dearborn said. If not maintained properly, a frog can cause a train to derail.

“Welders build up where the train wheels hit, or hammer down, in the frog area of a switch,” Dearborn explained.

Next time you spot a Metra crew on the tracks near Techny Road, you can guess they might be working on the “frog”—protecting the thousands of trains that pass through the town day in, day out, 24 hours a day.