MTO completed the Preliminary Design and Class EA Study for the 26 km section of Highway 404 from 407 ETR to Green Lane, in the Regional Municipality of York from 2014 to 2016.
The objectives of the previously completed Preliminary Design study were to assess and identify rehabilitation, safety and operational improvements throughout the study corridor and develop a plan that includes contract staging and sequencing for future construction projects.
A Transportation Environmental Study Report (TESR) was prepared to document the potential environmental effects associated with the Recommended Plan, proposed mitigation measures and commitments to future work. The TESR was released for a 30-day public review in June 2016, and received environmental approval in August 2016.
The EA Approved Plan that will be further refined during this Detail Design Study includes:
- Widening Highway 404 to include the addition of one HOV lane (3.75 m) and associated buffer (1.25 m) in both the northbound and southbound directions from the end of the existing terminus to Stouffville Road. The proposed HOV lane expansion will occur within the existing median of Highway 404, between the existing northbound and southbound lanes;
- Recommendations for replacing or rehabilitating the existing structures (i.e., bridges and culverts) to extend the service life of the structures and/or accommodate the capacity / operational improvements to Highway 404;
- Additional illumination will be provided as required;
- Implementing stormwater management and drainage improvements; and
- The addition of the west-north and reconfiguration of the south-east / west, and east-north ramps at 16th Avenue. The design and construction of these ramps will occur under a separate Detail Design Study once the Buttonville Airport ceases operation.