GO operates trains on its 65 Barrie line along the Newmarket Subdivison. GO and Metrolinx are already looking at ways to improve the southern end of this line, closer to Union Station, as part of the Georgetown South Corridor study.

In its strategic plan, GO 2020 (.pdf), GO sets out plans to expand service on this line. It hopes to operate trains all day, every day in both directions between Bradford and Union Station. But CP operates many freight trains along the North Toronto Subdivision and those trains would often block GO’s commuter trains — unless it can work with CN to remove the bottleneck at the Davenport Diamond.

Although the double-track North Toronto Sub does not yet carry GO trains, in June, 2007, Ontario Premier Dalton McGuinty identified a midtown GO service between Weston Road and the Don Valley as the 13th priority of his list of MoveOntario 2020 projects.

Metrolinx’ Regional Transportation Plan, “The Big Move” also prioritizes a rush-hour commuter rail service along the North Toronto Subdivision within the next 15 years. GO would likely operate some of its 21 Milton line trains over this crosstown line to help alleviate rush-hour crowds at Union Station.

GO recently consulted the nearby community to present options for redesigning the Newmarket Subdivision between Bloor Street West and Rogers Road.

GO presented three concepts.

• The first concept proposed lowering the tracks from north of Wallace Avenue to south of Rogers Road, so that trains passed beneath new bridges at Dupont Street, the CP North Toronto Subdivision, Davenport Road and St. Clair Avenue West. This model recommended a double-track Newmarket Subdivision, with one track for CN freight trains and the other for GO trains.
• The second concept proposed raising the tracks onto a concrete structure from south of Bloor Street West to Davenport Road. In this proposal, GO and CN would raise the current bridges at Bloor, Dupont and Davenport and build new bridges to cross Wallace Avenue and the CP tracks. This model recommended a double-track Newmarket Sub, with one track for CN freight trains and the other for GO trains.
• Similarly, the third concept also proposed raising the tracks onto a retaining wall, this time from just south of Wallace to just south of Davenport. This proposal required raising the current bridge over Dupont Street and building a new bridge across the CP tracks. This proposal might require the City to permanently close Wallace Avenue to pedestrians and vehicles.

GO expects to proceed with the formal environmental assessment of these three proposals later this year.

You can find out more about the project here. (.pdf)

GO recently finished two other grade separation projects at two other diamond crossings.

In June, 2007, on the same line, it finished a 17-month project to eliminate the Snider Diamond. During that project GO and CN raised the same line, the Newmarket Subdivision, so that trains could cross CP’s busy York Subdivision, just north of Steeles Avenue West in Vaughan.

For the Hagerman Diamond, GO and CN lowered Uxbridge Subdivision tracks — route of GO’s 71 Stouffville service — to eliminate the rail intersection with CP’s York Sub near 14th Avenue in Markham.

More recently, it announced a plan to separate CN’s Weston Subdivision from CP’s North Toronto Sub at the West Toronto Diamond — also part of the Georgetown South rail corridor project. And the provincial and federal governments recently funded a project to build a grade separation at Hamilton Junction, just west of that city near the Desjardins Canal.