- 6 km of 1650 mm diameter concrete-encased, cement mortar-lined welded steel pipe watermain along the Hydro Corridor (north of Finch Avenue) from Bayview Avenue to east of Pharmacy Avenue.
- 13 tunnel crossings including Highway 404 (120m) and CN Rail as well as the arterial roads (e.g. Bayview Avenue, Leslie Street, Victoria Park, Pharmacy Avenue etc) as well as other higher volume collector roads. The CN Rail tunnel was 2400 mm Concrete pipe.
- 32 valve chambers comprising 3 line valves, 9 drain valves, 10 air release valves and 10 access chambers.
As part of ongoing upgrades to the City’s water system, and specifically to meet the increased future water demands and supply to York Region, the route for this watermain was established in a previous Route Selection and Environmental Assessment Study prepared by CFA.
The Hydro Corridor route was strategically identified as being the most economical with mitigatable impacts.
A unique ‘open cut crossing’ of the Don River east branch included a comprehensive restoration strategy for the watercourse area and floodplain lands with native plantings.
CFA played a key role in negotiating permanent and temporary easements and crossing agreements along the Hydro Corridor (230 kv transmission lines) with Hydro One, Ontario Reality Corporation, CN Rail, and other secondary users of the Corridor such as Seneca College and some private churches.
Other approvals included MTO, MOE for dewatering and C of A and gas pipeline companies and the utility companies (hydro, bell, gas) for relocations and crossings.
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The City of Toronto retained Chisholm, Fleming and Associates (CFA) to provide full design and contract administration for the 1650 mm diameter watermain on along the Hydro Corridor (north of Finch Avenue) from Bayview Avenue to Brookshire Blvd., east of Pharmacy Avenue (6 km length) in the former Cities of North York and Scarborough . This project was commissioned as part of ongoing upgrades to the City’s water system, and specifically to meet the increased future water demands and supply to York Region.
The watermain route was established in a previous Route Selection and Environmental Assessment Study prepared by Chisholm, Fleming and Associates (CFA) for the City from Kennedy Road to Bayview Avenue. Although most watermain infrastructure are situated within the road allowances and public right-of-way, the route along the Hydro Corridor was strategically identified as being the most economical with mitigatable impacts.
Concrete encased, cement mortar lined welded steel pipe construction was used due to its high durability and construction qualities well suited to high density built-up, urban areas. The project included 32 valve chambers comprising 3 line valves, 9 drain valves, 10 air release valves and 10 access chambers.
Careful planning during design permitted construction along the Hydro Corridor amongst the 230kv overhead transmission lines/towers as well as the oil/gas pipelines situated along the Corridor. A corrosion assessment was also undertaken to ensure there were no negative impacts on the steel watermain plant given its proximity within the Hydro Corridor.
This project involved extensive tunneling comprising 13 tunnel crossings including Highway 404 (120m) and CN Rail as well as the arterial roads (e.g. Bayview Avenue, Leslie Street, Victoria Park, Pharmacy Avenue etc) as well as other higher volume collector roads.
A tunnel boring machine (TBM) was used for most crossings due to the extent of tunneling involved. However, the CN Rail tunnel was accomplished by pipe jacking (21400 mm Concrete pipe) and other shorter tunnel were constructed by conventional “hand mining” with steel liner plate.
CFA negotiated and develop the restorative strategies for an “open cut crossing” of the Don River east branch to secure TRCA and DFO approval due to the unsuitable ground conditions for tunneling,. A comprehensive restoration strategy was developed for the watercourse area and floodplain lands with native plantings.
Extensive liaison/co-ordination with various stakeholder groups and regulatory agencies were required for permits and approvals. CFA played a key role in negotiating permanent and temporary easements and crossing agreements along the Hydro Corridor with Hydro One, Ontario Reality Corporation, CN Rail, and other secondary users of the Corridor such as GO Transit (Old Cummer Station), Seneca College and some local businesses and a churches. Other approvals included MTO, MOE for dewatering and C of A and gas pipeline companies and the utility companies (hydro, bell, gas) for relocations and crossings.
Sub-surface Utility Engineering was utilized to accurately identify potential utility conflicts and to plan an effective utility accommodation and relocation strategy prior to construction.
Public meetings and community liaison with the local residents and businesses along the watermain route was undertaken by CFA. A Multi-use path was also incorporated into the overall restoration strategy for the project.