Lemieux Island Water Purification Plant Intake Improvements

The City of Ottawa is proposing the construction and operation of a new raw water intake pipe in the Ottawa River for the Lemieux Island Water Purification Plant (WPP) located in Ottawa, Ontario. Over the past few years the existing water intake pipe has been vulnerable to the buildup of frazil ice (i.e., slush and ice) in the winter, which restricts raw water intake and affects the supply of potable water to the east end of the City, which includes the downtown core. To mitigate against frazil ice, the proposed intake pipe will extend further offshore, in a deeper part of the Ottawa River, with a water depth between 15 and 17 m.

The construction of a temporary dock and temporary staging area are required to support the in-water works associated with construction of the new intake pipe. This temporary dock and temporary staging area will take place on leased National Capital Commission (NCC) land, along the shore of the Ottawa River, west of Vimy Place and the LeBreton Flats. The dock footprint will be at most 175 m2 and the temporary construction easement will be 261 m2. The staging area will be on land, adjacent to the dock, and will have an area of approximately 5500 m2.

Since this project involves NCC federal land, the project requires an approval under the National Capital Act. This project also involves Transport Canada, as the new pipe and temporary dock require an authorization under the Canadian Navigable Waters Act.

The project will take place over 2 years with a potential start in 2024. In-water works are permitted by Fisheries and Oceans Canada (DFO) from July 15  to March 31  and will occur in two (2) phases to comply with this requirement. Other mitigation measures to safeguard the local environment and socio-economic conditions will be implemented as determined by the environmental review of the project and applicable laws and regulations applicable to the project.


Latest update

May 4, 2023 – The public comment period on the project is closed. The National Capital Commission is considering comments received to help inform its determination on whether the carrying out of the project is likely to cause significant adverse environmental effects.


Key documents

Key documents
Document Number Document Title File Date
1 Notice of Intent to Make a Determination - Start of Public Comment Period - April 4, 2023


National Capital Commission
Environmental Assessment
40 Elgin Street
Ottawa, Ontario K1P 5A8
Email: IA-EI@ncc-ccn.ca

  • Location

    • Lemieux Island Water Purification Plant (Ontario)
  • Nature of Activity

    • Water Management
  • Assessment Status

    In progress
  • Start Date

  • Proponent

    National Capital Commission
  • Authorities

    • National Capital Commission
    • Transport Canada
  • Assessment Type

    Project on federal lands
  • Reference Number


This map is for illustrative purposes. The markers represent the approximate locations based on available data. More than one marker may be identified for a given assessment.


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...within 200 kilometres
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