The Waterfront West LRT line would run for 11km, estimated to account for 21 million trips in 2021. The western terminus of the line would be built at the Long Branch GO Station in Etobicoke. The line would use an exclusive right of way along Lakeshore Boulevard West, and follow the existing right of way used by routes 501 and 508 through Humber loop, and along the Queensway. A new right of way would parallel King Street West east of Roncesvalles Avenue, and follow the rail corridor to the existing Exhibition loop facility. From there, the preferred route to Union station would run under the Gardiner Expressway through the southern edge of Fort York and enter a right of way on Fort York Boulevard just west of Bathurst street. The line would tunnel under the Air Canada Centre in order to reach the existing Bay Street streetcar tunnel and terminate at nearby Union Station.
The TTC has predicted an average daily ridership of over 40 000 on the segment that would serve the developing Liberty Village and CityPlace neighbourhoods, as opposed to approximately 2 200 per peak hour on the western segment of the line. Based on these numbers, there is concern over the capacity of certain intersections. This is the main reason why the proposed LRT will likely not use the existing right of way along Queens Quay West, as the intersection at Lakeshore Boulevard and Bathurst has prohibitively long light cycles.