Not sure if it's been discussed before, probably has. But I was thinking about "interlining" of subway lines (similar to the short-lived Yonge-Bloor-Danforth in the 60s), and thought how costly/complex it would be to interline Sheppard/Line 4 with Yonge. So basically the Sheppard stub would become
two lines: Line 1 and Line 4. The majority of Sheppard's service would be 6-car Line 1 trains (that bypass Sheppard-Yonge station), while the current 4-car Yonge-Don Mills shuttle would run similar to how it does today - albeit less frequently (e.g 15mins).
AFAIK the N/B Yonge track leads to Sheppard E/B. With ATC in a place and one or two new crossovers, I can't really see why this would be an extreme challenge or costly endeavour. As for wayfinding, the second interline on Sheppard could be shown as a branch of Line 1, or as another Line # sharing the majority of Line 1's route.
Has anything similar been officially considered by the TTC? Considering the majority of Sheppard's riders are headed S/B in the AM peak, would there be merits to this?
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