How much snow is too much?

Just had a question from a friend of mine that I just didn't have an answer for. He ask how much snow is to much for a train to make it through. I know that a lot of the problems come from down wires and trees etc, but how much snow does it take to actually keep trains from running?

Thanks

Depends to a large extent on motive power, and if you're talking passenger or freight.

Diesel passenger runs can generally operate in heavier snow conditions than overhead electric-powered, and overhead-electric powered runs can generally operate in heavier snow conditions than third-rail powered, which are the first to suffer (maybe 8-10" of snow is too much for them).

With freight operations, you've also certainly got to consider the number of cars, weight of consist, grades, etc.

Also, don't forget the affects snow can have on electrics as well ... either into traction motors or ingested into air intakes for equipment and motors ...

Case in point, look at the shutdown of the Channel Tunnel a few weeks back, which was caused by snow ingestion into the electrical cabinets of the electric locomotives ...

- litz