As part of their Watermain Management Program and the Toronto-York Region “Joint Optimization Study,” Toronto Water determined that the existing cast iron watermain (Main 20) along Avenue Road should be replaced to increase security of supply, and improve system hydraulic performance. Associated Engineering was retained to design the replacement watermain, which consisted of approximately 3.5 km of 900 mm diameter and 2.1 km of 750 mm diameter pipe. The new watermain alignment is located predominantly along Avenue Road, starting at the City’s High Level Pumping Station located on Cottingham Street, and extending to the connection point located at Avenue Road and Caribou Road.
Associated Engineering provided project management, contract administration and inspection services throughout the 2.5-year construction period. The final design allowed the existing main to remain in operation until the appropriate connections to the new system could be made. Included were three trunk watermain and fifteen branch connections. The final design included 2.8 km of open cut installation and 2.8 km of tunnelling installation, requiring both pipejacking/hand mining and microtunnelling techniques.