I am surprised this country still has wood trestles. I know you can inject chemicals into them to greatly extend their life but I think railroads should have replaced them by now.
Don’t forget the Ice Ages that were a force in shaping the North American continent, were water in its solid form.
A lot of the damage that resulted from the eruption of Mt. Saint Helens was from the steam that resulted from the magma contacting the snow pack on the mountain.