Commuters travelling downtown this morning may need to look at alternative routes.

An “environmental spill” at College Station shut down the Yonge-University-Spadina line between Bloor and Union Stations shortly after 8:30 a.m., according to a press release from the Toronto Transit Commission this morning.

The TTC has dispatched 70 shuttle buses to run between Rosedale Station and St Andrew Station. The buses are bypassing Union Station.

TTC CEO, Andy Byford, said it may be a while before the situation is resolved.

“Our estimation is we probably need another two, maybe three hours to not only fix this, but clean up the mess,” Byford said at about 11 a.m. today.

According to Byford, the delay was caused by a gasoline or fuel-like substance leaking in College Station.

Byford said they were aware of the problem Monday night but didn’t realize the severity until early this morning. At first they thought it was water but later found out it came from an expansion joint.

— with files from Matt Green