Tunneling

Scope

The McOrmond Drive sewer trunks project will service the new developments on the East side of the rapidly expanding city of Saskatoon, an area close to 2,533 hectares. The parallel tunnels both run a length of 1500 metres at a below ground depth of approximately 14 metres.

The project consists of sanitary and storm sewer trunks with inside diameters of 1200 millimetres and 2400 millimetres respectively as well as large soldier pile and lagging launch and reception shafts. Three smaller intermediate manhole shafts of varying sizes were also installed with circular ring steel and lagging. Both tunnels are a two-pass system with rib and board as the external support and centrifugally-cast fibreglass reinforced polymer mortar (CCFRPM) for the inner liner (Hobas pipe) Excavation was completed using an Earth Pressure Balance Tunnel Boring Machine (EPBTBM).