The MacMillan Yard is the largest rail classification yard in Canada. It is operated by Canadian National Railway (CN) and is located 20 kilometers north of downtown Toronto in Vaughan, Ontario. It is named after former CN president Norman John MacMillan.
MacMillan Yard is located at the junction of the CN York Subdivision and CN Halton Subdivision. The yard measures 4 miles in length and 1 mile in width with a north-south orientation. The property is bordered by four main roads:
- Highway 7 (York Regional Road 7) to the south
- Keele Street to the east
- Route 73 (Rutherford Road) to the north
- Creditstone Road to the west
There are five road entrances into the yard which are designated as: S Yard, Jane Street, CargoFlo, Bowes, and Administration.
Much of the yard is composed of side-by-side track, switches, humps, and control tower buildings. The yard is designed to take incoming trains and reorganize and rejoin the individual cars based on destination to create new departing trains. The yard operates 24 hours a day and handles over 1 million cars (loads and empties) per year. It has flat switching capability as well as both dual and single humps. In addition to car handling, other yard facilities include locomotive repair, car washing, and car repair. In one part of the yard, a CargoFlo terminal is used for transferring flowable bulk, dry bulk (plastics) commodities between rail cars to tanker trucks, as well as a small intermodal and RoadRailer operation.
The yard was developed in the late 1950s as part of CN's redesign of its Toronto trackage network. At the time of construction, Vaughan was a largely rural community, however, subsequent development on adjacent properties has created an industrial area surrounded by a variety of industrial consignors, distributors, and suppliers. Some commercial establishments (e.g., restaurants, retail and wholesale outlets) are located along the perimeter of the yard.
The closest residential population to a track that carries dangerous goods is located approximately 150 meters from the northernmost extension of the yard near Jane Street. At the southern end of the yard, where several rail lines merge, Highway 7 provides a road bridge. Toll Highway 407 also bridges the southern entry point to MacMillan Yard; all trains enter and exit by way of southern end.
On July 29, 2015, 91 freight cars ran away in the CN MacMillan Yard after they separated from a switching locomotive. Nine of those freight cars derailed and two freight cars on an adjacent track were damaged when the runaway cars collided at low speed with other cars that were a part of an incoming train in the yard. No injuries were reported. The Transportation Safety Board sent two inspectors to the site to investigate the incident.