Originally Posted by
BuildingMyBento
Segmented lines refer to ones not yet in operation...though I didn't realize the website lacked that info. Still, it's good about providing sources, and detailing what (and where) future lines are in store.
Urbanrail map is also very good and yes it makes it obvious what is under construction. It's a great site overall. The future line info is also very good but I'm completely biased in stating that......