Public Notice

Ottawa River Outfalls Rehabilitation Project – John Street Outfall (OUT04455) – Public Comments Invited

August 8, 2024 – The authorities must determine whether the proposed Ottawa River Outfalls Rehabilitation Project, located in Ottawa, Ontario is likely to cause significant adverse environmental effects.

To help inform this determination, the authorities are inviting comments from the public respecting that determination. All comments received will be considered public and may be posted online.

Written comments must be submitted by September 8, 2024 to:

Environment, Health and Safety

Public Services and Procurement Canada

11 Laurier St, Portage III, Place du Portage
Gatineau, QC  K1A 0S5

Email: TPSGC.RCNLVEEListedeControle-NCRECMPChecklist.PWGSC@tpsgc-pwgsc.gc.ca

 

The Proposed Project

The City of Ottawa is proposing the replacement of existing City owned twin outfall pipes that are partially on Federal Lands owned and administered by Public Services and Procurement Canada (PSPC), and lands under the jurisdiction of the Province of Ontario, located behind the French Embassy at 42 Sussex Drive, Ottawa, Ontario (See figure below). The existing outfall is a twin 1,500 millimeter (mm) diameter (dia) storm sewer that discharges stormwater from upstream urban lands to the Ottawa River; the outfall pipe extends approximately 100 meters (m) into the river. Previous condition assessments have determined that the existing pipes are in very poor condition and have been recommended for replacement. The City proposes to install a new single 2,100 mm dia outfall pipe to be located on and within the bed of the Ottawa River, perpendicular to the shoreline and immediately upstream of the existing outfall pipes. The new pipe is proposed to extend approximately 120 m into the river. The existing pipes will be removed to accommodate the proposed single pipe. At the shoreline, a new manhole drop structure will be installed adjacent to an existing manhole, where the new pipe will be connected. Ice-scour protection for the proposed outfall will be provided through an Articulated Concrete Block Mattress (ACBM) system, placed on top of the proposed pipe. Dredging of the river bottom from a barge within a turbidity curtain area will be required for the new pipe installation (and removal of the existing pipe), as well as excavation of the shoreline to enable the installation of a new manhole drop structure. A cofferdam will be required at the manhole location to isolate the work area.  Construction access to the site will occur via an existing access, located behind the French Embassy; the application of granular material and some vegetation removal is expected to prepare the access. Two additional granular pads will be constructed adjacent to the existing manhole structure and shoreline to provide a working area for equipment. A temporary dock at the shoreline, constructed using pre-cast concrete blocks and filled with clean granular material is anticipated to enable barge access. Areas disturbed by construction will be reinstated.

Incidental to the Project, the use of the existing National Capital Commission (NCC) Blair Road Boat Launch and associated gravel parking area, located approximately 6.5 kilometers (km) downstream of the John Street Outfall site will be required for temporary staging to prepare the new pipe for installation. Once prepared, the proposed pipe will be floated upstream with the aid of barges and sunk into place at the John Street Outfall site. While no physical modifications to the existing Blair Road Boat Launch site are required, the NCC will issue a land access permit and a federal approval under the National Capital Act to enable the project to proceed. Pedestrians using the existing Ottawa River Pathway that crosses the boat launch will be detoured through the use of signage.  Use of the launch will be off limits to the public for a period of 3 – 4 weeks in September 2025.  In addition to PSPC and the NCC, the Department of Fisheries and Oceans Canada and Transport Canada also have a trigger to make a section 82 determination under the Impact Assessment Act for this project stemming from a permit under the Species at Risk Act and an authorization under the Canadian Navigable Waters Act, respectively.

The detailed design is being finalized for the Project. Construction is expected to commence in the summer of 2025 (dependent on available City funding), with a duration of approximately 5-6 months.