TTC riders are being told to prepare themselves for major downtown service disruptions beginning this weekend and moving through to the end of August.

Between 9 a.m. and noon on Sunday, shuttle buses will be running between St. George and Pape subway stations on the Bloor-Danforth line as the TTC conducts track work on the Bloor Viaduct. Wheel-Trans buses will be available for passengers requiring accessible service.

Subway service will resume as normal at noon.

On Monday, major construction begins at the intersection of Dundas Street West and Spadina Avenue as the city replaces an aging watermain and the TTC makes necessary track and switch repairs.

Starting Monday, the 505 Dundas streetcar will reroute in both directions via Bathurst Street, College St., and McCaul Street, and the 510 Spadina streetcar will be replaced with buses.

Riders can expect at least seven weeks of service changes and delays on and around Spadina Avenue as the TTC readies the route for a brand new fleet of air-conditioned, wheel-chair accessible streetcars on August 31.