Slippery Rail, How It Affects Your Commute, And What We Are Doing To Combat It

In autumns past, you may have heard our train crews mention "slip-slide" to explain minor service delays. This condition is created by a slimy substance left by crushed leaves on our rails that gets even more slippery after it rains.

When a train attempts to speed up or slow down, this gelatinous "slime" can cause the wheels to slip or slide along the rails. In severe cases the train will automatically make an emergency stop, because the on-board computer system perceives "slip-sliding" as excessive speed. And this slip-sliding and braking can also create flat spots on the train's wheels, forcing us to take much-needed equipment out of service for repairs.

Over the past several years, we have taken a very proactive approach to combating this problem, and you've been experiencing slippery rail less and less frequently.

Changes we have enacted include:

• Instructing our engineers to report slippery conditions immediately to our Operations Control Center. (We have also provided additional training in how to operate through these "slippery" areas.)
• Enhancing our computerized train-tracking system to allow for automatic reporting of slip-slide incidents and conditions, enabling us to take corrective action more quickly.
• Installing a Wheel Impact Load Detector (WILD) across all four tracks in the Park Avenue Tunnel. This monitors for wheel flats that may have developed during operation and allows us to identify and prioritize wheels for repair.
• Installing a tandem Wheel Truing Lathe in Harmon Shop. We built a state-of-the-art wheel true facility in Harmon that can cut both wheels on a truck simultaneously. This allows for proper wheel diameter matching and also helps us return cars to service more quickly so we have enough cars available for our customers. CDOT is currently building a second identical facility in New Haven to support our new M8 Fleet. This new addition is scheduled to be completed for the Fall of 2013.

Many of you may notice that under extreme conditions, we now reduce speeds through problem areas. While this may result in a slight delay to your service, it ensures safe operation of our trains and also prevents a greater delay because of wheel damage. And no flat spots on train wheels also means we can operate at regular speeds in non-problem areas, and we don't need to take the equipment out of service to maintain it.

We have also stepped up our efforts to keep our right of way as "leaf free" as possible. (This is no small feat given the number of trees that line our tracks.) We use rail washers and scrubbers more frequently to remove dead leaves from the tracks. And on-board "sanders" on our trains automatically drop sand on our tracks to help improve traction and reduce wheel slippage when it begins to occur.

We please ask that you keep in mind that while we can reduce the incidents of slippery rail, we cannot eliminate them. We will continue our efforts to try to minimize any delays and inconvenience slippery rail may create for you this autumn. And, as always, we appreciate your patience.