The City of Windsor is warning of potential delays that could impact regular tunnel bus service should job action be taken by 9,000 Public Service Alliance of Canada (PSAC) members who work for the Canada Border Services Agency (CBSA).
If a deal is not reached, job action could begin at 4 p.m. Friday.
The city states Transit Windsor's service to Detroit will remain in operation as normal, and the situation will be monitored for any changes.
"Our Tunnel Bus is just like any personal or professional vehicle crossing our border," said Transit Executive Director Tyson Cragg. "We're not immune to delays, so we just want to ensure riders know we could all face delays when returning to Canada."