The Warm Springs Sub is virtually a stub line between Niles and Warm Springs; from Warm Springs north, the line sees several trains, including autoracks, locals, and a BNSF turn from Richmond. As I understand it, the UP agreed with the city of San Jose to limit traffic on the southern portion of the line to one round trip a day because of traffic congestion and the myriad of grade crossings on the line. UP used to run a yard job from San Jose up there midday, but now that the San Jose yard is gone, I suppose it comes from Warm Springs.