A little while back, Spacing Ottawa published an op/ed piece by Dwight Williams with a suggested way to link the City of Ottawa's two biggest public construction projects: the redevelopment of Lansdowne Park, which is currently not served by rapid transit, with the construction of an east-west LRT line with a tunnel under downtown. Williams' suggestion? A light-rail transit line that tunnels underneath Bank Street at some points, and parallel to at others.
The system map presented above (which you can click to enlarge, and was made with information from Spacing's image) is a rough (and not nearly to scale, I realize) estimation of what this integrated system could look like. The blue line is the current O-Train, the red line is Ottawa's current east-west line, and the green line is Williams' proposed Bank Street line, which I've made the executive decision to connect to the Downtown East station (which would likely be between Metcalfe and O'Connor streets downtown). It does connect the "red line" with the "green line" quite nicely, bringing people from downtown to Lansdowne--as well as Billings Bridge, the Glebe, and other destinations--comfortably and quickly. The inclusion of a Sunnyside Station, which would actually be fairly close to the O-Train's Carleton University station, also brings those lines together.
As it stands right now, there is nothing of significance, public transit-wise, for Bank Street. In the city's Transportation Master Plan update released in 2008 (.PDF, network map on page 1), a small portion runs along Bank Street near Greenboro Station, but other than that, Bank is reserved for local bus routes, personal automobiles, and human-powered forms of transportation.
So, can we have light rail on Bank Street? Well, we probably could, and it would certainly go a long way in solving the transportation problems around the Lansdowne Park redevelopment. But it wouldn't be cheap, and it wouldn't be easy. The cost of tunneling where necessary, and to join up with the Downtown East station, immediately raises questions of cost. Actually building the line would be hard, given that Bank Street is pretty much always busy as it is. And finding the political will to push for this kind of project won't be easy: Since Bank Street isn't really identified as a target zone for rapid transit currently, changing the master plan to put a priority on it would take some real negotiating and gesturing--especially since doing so would likely delay the expansion of light rail further east, west, or south into suburbs like Orleans, Kanata, Barrhaven, and Riverside South.
A terrific idea which would most certainly connect Lansdowne to our current and future public transit systems, but not one without significant hurdles to get over.