Kennedy Road Water Main Installation
Project Highlights
Role: General Contractor
Project Delivery: Design-Bid-Build With design-build VECP
Tunnel Equipment: 2.6m & 2.7m EPB TBMs
Primary Support: Gasketed steel segments, welded steel casings, AWWA C200 pipe
Ground Conditions: Soft ground & mixed face, artesian hydrostatic pressures
Project Description
The Kennedy Road project required the installation of 3300 meters of a1500mm diameter watermain by tunneling and open-cut methods along with valve chambers and appurtenances, connections to existing watermains and restoration of all areas. The project included various crossings including tunnelling under Hwy 407, CN Railway, GO Transit railway, Rouge River, York Durham Sanitary Sewer (YDSS), numerous local roads, and various subsurface utilities. Crossings under Hwy 407, CN Railway, and GO Transit required strict compliance with each of the authorities’ requirements and permit stipulations. All crossings were completed accordingly with all applicable securities, work plans, and methodology submittals completed to the satisfaction of each authority.
The 1500mm diameter watermain was installed in a busy urban environment located in Markham, Ontario. Excavation took place from Milliken Pumping Station on 14th avenue and along Kennedy road from 14th avenue to connect to an existing 1500 mm diameter watermain near the GO Transit Railway tracks and along Highway 7. Watermain installation on the project also involved approximately 300 meters of 1500mm diameter C301 via open cut.
Work areas, construction traffic, and various surface activities (such as settlement monitoring, open cut installation, connections, and etc.) were carefully planned and executed to comply with the project requirements, road occupancy permits, and to minimize impact to local traffic and the neighboring transit hubs.
The project utilized 2.7 meter and 2.4 meter, EPP TBM and included the installation of a 2700mm and 2400mm steel segmental, gasketed tunnel liner as primary support. Multiple runs were constructed at 210 meters, 1510 meter and 1052 meters. The segmental steel liners were installed behind the two TBMs to combat the extremely soft, wet and artesian ground conditions which had water pressure of up to 14 psi. Tunneling in EPB mode was required in order to deal with the varying ground conditions encountered throughout the project and also to counteract the artesian ground water conditions.
Owner: The Municipality of York
Drive Length: 2850 meters
Diameter: 2.4m & 2.6 m
Consultants: MMM Group Limited
Contract Amount: $42,478,497
Ground Conditions
Subsurface conditions along the tunnel alignment generally comprised of surficial fill and topsoil overlying sand and silt till deposits which was underlain by a silty sand. Thin layers of discontinuous cohesive soils of clayey silt and silty clay were present. Extreme rock content (300x the GBR baseline in one section), i.e. cobbles and boulders, was encountered during tunnelling. The fill along the tunnel alignment was generally heterogeneous, its thickness was variable and very often mixed with organic matter and topsoil and debris.
The project utilized in-house fabricated steel waterproof gasketed tunnel liner plate as primary support behind the two EPB Tunnel Boring Machines for extremely wet and artesian ground conditions with water pressures of up to 1 bar (14psi). 1800mm steel casing was installed for secondary support underneath the Rouge River crossing. Work on this project was completed within a busy central area of the City of Markham.
