@nomi I think "profitable" is less the benchmark than "the most effective use of the transit dollars". Where do you put a railroad that couldn't be more cheaply served by a bus route on existing infrastructure? Setting aside a lane for buses during rush hour, like we have on 670, gets you most of the benefits of a grade-separated railway.
Apart from the expense of buying up the right-of-way and constructing the tracks, bridges, etc., trains have a few inefficiencies relative to buses:
- They can't make temporary detours. If a storm damages the line (freezing rain on the catenaries, for instance), the trains are stuck until repairs are made.
- It's extremely expensive to permanently reroute the line when needed. The greyhound station was recently relocated a couple blocks over, and COTA just adapted the bus lines to the new transit centre. They couldn't have done that with trains.
- The space can't be used for anything else. On off-peak hours, the bus lane can be designated a carpool lane, emergency vehicles can bypass traffic to reach an accident, etc. Train tracks just sit empty.