Ministry of Public and Business Service Delivery
The TTC built the original Yonge subway in seven sections to ensure completion of the entire line at approximately the same time, and to minimize the impact on surrounding businesses and street traffic.
“Cut and cover” method was used to build much of the line. In this method, construction workers opened up the street, excavated material, and then temporarily covered the route so it could carry traffic while work continued underneath. Once the section was complete, crews covered the street permanently and installed new pavement.
The advantages of this method of construction included reduced construction cost and the ability to build the subway much closer to the surface to improve passenger accessibility.