The possibility of converting the Scarborough RT to true LRT when its current fleet reaches the end of its life, instead of conversion to ICTS Mark-II, is still being considered by the TTC.
In the supplementary agenda for the October 23 TTC meeting, the status update on Transit City includes a section on the planned upgrading and extensions of the Scarborough RT. The following paragraph appears in the document:
The project team is currently re-visiting the option of converting the Scarborough RT from its current vehicle technology to light rail technology, when the current fleet of vehicles reaches the end of its service life. Such a conversion is being investigated as a means of providing more routing flexibility, and in order to take advantage of possible benefits of a vehicle technology which would be common to the other Transit City lines. In support of this option, a structural analysis is underway of the existing Scarborough RT infrastructure. The project team is continuing its work on the development of conceptual designs for a new maintenance facility.
In my opinion, this conversion would be a wise choice. When looking at converting the existing SRT to either ICTS Mark-II or LRT, the LRT option is slightly more expensive. However, when one considers extending the line, the cost per kilometre is significantly less for the LRT option. Furthermore, the benefits of using the same technology as the rest of the Transit City network is immense.
Though actual use traffic patterns will dictate what routes will operate, I strongly suspect that at least during rush hours it will be convenient to have split operations on both the Sheppard route and the SRT route. What I mean by this is that the Sheppard route could see some running all the way along Sheppard to Meadowvale while some would branch to Malvern Town Centre, and also the SRT could run with these two same destinations in the northeast. This would provide no transfer service from Malvern Town Centre to Scarborough Town Centre and Kennedy as well as to points west along Sheppard and the same thing from points east along Sheppard.
In actual use, if the first LRT arriving was not the one you need for a transfer-less journey, you could either wait for the one you want, or you could take it to the transfer point. It is very likely that you might get to your destination earlier by opting for the transfer choice. I have experienced this very type of service as it currently exists in Denver. Take a look at my Denver page to get an idea of how the routes work with this sort of interlining. There are five routes forming an “X” between the southwest suburbs, southeast suburbs, and western and eastern downtown areas. They all interline for three stations where one can transfer if the train they are on is not going to their destination. There is a similar interlining arrangement in the southeast suburbs where a branch provides routes to downtown and a suburb-to-suburb route.