Portlands Flood Protection 33.6 – Polson Slip Wet Excavation and Finishes | Projecs

Overview

QM Environmental was awarded the RFP 33.6 Subcontract as part of the Portlands Flood Protection and Enabling Infrastructure project in Toronto.

The scope of work involved:

Demolition of a historic dockwall
Dry and wet excavation, including dredging
Management and tracking of excavated material
Underwater placement of marine geotextile
Underwater placement of a subaqueous barrier layer comprised of granular activated carbon
Placement of river finishes

QM Environmental conducted this work using conventional and long-reach excavators from land and a floating barge section. All work was undertaken in a turbidity curtain to prevent turbidity from entering the Toronto harbour.

QM Environmental Services:

Dry excavation of over 3000 m3 of material
Wet excavation/dredging of over 13,000 m3 of material
Demolition of over 65m of dockwall
Placement of approximately 3300m2 of marine geotextile underwater
Placement of 3300m2 of a subaqueous barrier layer (granular activated carbon)
Placement of over 2000MT of river finishes, including rip-rap, armour stone and habitat boulders
State-of-the-art survey using grade control and bathymetric survey techniques to document underwater conditions
State-of-the-art soil tracking and data management using proprietary software
Removal of historical, unknown underwater structures such as timber piles, walers, etc.
Monitoring of dockwall for vibration during periods of active construction work.