- Management of project objectives, staffing and costing, and scheduling
- Direction of the design team
- High level technical/design assistance and guidance
- Implementation of quality control and management of project delivery
- Engineer of record
- Client, public, stakeholder, and sub-consultant liaison
In 2015, the City of Toronto initiated design and construction of a 1,050 mm (42 inch) diameter watermain from the Scarborough Pumping Station (SPS) to the intersection of St. Clair Avenue and Midland Avenue. The section of watermain along Claremore Avenue included a 150 mm watermain replacement. The 3.0 km (9,842 ft) trunk watermain will improve system hydraulics and augment supply in the City’s Pressure District 4. Approximately 670 m (2,200 ft) of the watermain is to be built by trenchless technology and the remainder by a combination of open-cut and cut-and-cover methods. The tunneling portions of the watermain will cross underneath highly congested utility corridors, vital telecommunication infrastructure, and major arterial roads. The Scarborough Trunk Watermain (STWM) project is one of the first undertaken by the City after releasing its Standard Specification TS 7.80 for Large Diameter Watermains. Construction started in the fall of 2018.
As a subconsultant to the prime consultant (Hatch), CFA completed the design and provided inspection and contract-administration assistance for approximately 2 km of 1,050 mm watermain as well as the 150 mm local water through a fully built-out residential neighborhood. Open-cut construction was used as the more cost-effective construction method, with construction staged to continuously maintain local traffic through the project site.
An approximate 900 m (2,950 ft) long section of the watermain currently being installed along Claremore Avenue was initially planned to be in the east boulevard, but on further evaluation it was located onto the paved road to avoid removing 54 mature trees and having an impact on residents’ front yards. This revised alignment left the design team with the challenge of placing the pipe in a limited and busy corridor. To add to the complexity of the route selection, there is an existing 60-plus-year-old 150 mm (6 inches) cast-iron local-distribution main adjacent to the east curb. The need to replace the aged main was identified and added as a part of the project scope.
Two alignment options for the replacement of the existing local main were evaluated. Both options had the watermains being installed in a trench to accommodate corridor constraints. While both options were found technically feasible, the team opted for the alignment that had a lesser impact on the existing curb, sidewalk, and mature trees.