Highways 3 and 4 near St Thomas will be getting significant upgrades soon.
The province has started an environmental assessment study to widen the Highway 3 bypass in St Thomas from 2 to 4 lanes between Centennial Avenue and Ron McNeil Line (near Wonderland Road). Additionally a new four-lane Highway 3 bypass will be constructed from Ron McNeil Line to Highway 4 which will bypass Talbotville
Highway 4 will also be widened from Clinton Line to the future Highway 3 bypass. This effectively means that there will be a 4-lane connection from the 401 to east St. Thomas.
Edited to add: In the coming months, there will be public information sessions which will reveal the specific design choices "including construction of new roundabouts or interchanges, culverts, and bridges".
Project Website:
www.highway3elgin.ca
Notice of Study Commencement:
https://highway3elgin.ca/resources/notice_study_commencement.pdf