It’s that time of the year again – leaves are falling and the rainy season starts, leading to a lot of wet leaf buildup on the rails – a well-known problem in the rail industry. You’ll hear a lot of sand being dumped in this kind of weather to help give the trains traction. It’s especially problematic downtown, where city workers use their leafblowers to blow the leaves from the sidewalk (good!) into the right of way (bad!), probably not realizing the hazards that can cause. Remember that the rail downtown is girder rail:
That grooved area gets filled with the leaf debris which is dangerous. The train wheels need a clear area to pass through there while maintaining contact with the rail at all times – it is possible for leaf debris to insulate the electrical circuit between the train and the rails, and also possible for the train wheels to leave the rail if that groove is filled with enough debris. Around switches, the leaf debris can prevent the switches from being fully set (and the extra sand being dumped for traction doesn’t help either). You’ll see track maintenance people keeping the rail cleared to mitigate these problems.
Overall TriMet passengers aren’t generally affected by delays due to leaf buildup, but be careful when walking across pedestrian crosswalks over the rails and please do not blow, dump, rake, or otherwise deposit leaves in the right of way.