Slippery Rail Season

Fall brings stunning displays of colorful foliage along many Metra lines, but it’s also responsible for a much less enjoyable seasonal phenomenon: slippery rail.

What is slippery rail?

Leaves fall and land on train tracks where they are then crushed by passing trains, creating a slick, oily residue on the rails. This residue decreases the friction between rails and train wheels, creating slippery rail conditions that make it difficult for trains to gain the proper traction to start, stop and maintain speed. These conditions can result in unfortunate delays and other inconveniences for riders.

In recent years, the implementation of the Positive Train Control (PTC) safety system has also been a factor in these delays. PTC is designed to stop speeding trains. When a train’s wheels slip, the onboard computer system incorrectly interprets the wheels spinning on the slippery rails as the train traveling faster than allowed, causing the system to stop the train. The system must then be reset for movement to resume. PTC system software has been updated to try to address these recent issues.

What does Metra do to prevent slippery rail?

Metra takes a proactive approach to mitigating slippery rail delays every year. Crews use two machines with a wire brush that runs along the top of the rail to remove leaves and residue. These machines are towed behind a hi-rail truck (a pickup truck that can operate on train tracks and a road) throughout the fall, with special attention paid to problem areas with lots of trees or hills such as the Milwaukee District North Line and the Beverly Branch of the Rock Island Line. This effectively removes leaf residue, but slick conditions can still occur between brushings.

How will I know if slippery rail is affecting my train?

As we do with all service disruptions, Metra uses all communication resources at our disposal to keep customers informed when slippery rail conditions cause any delays or disruptions. This includes service alerts posted on this website and on Twitter, email alerts, and announcements at stations and on trains.