Study area

Before determining the line routes and location of the substation, Hydro-Québec surveyed a study area of some 40 km2 to better understand the host environment.

Map of the study area for the Patriotes project [PDF 37 Ko]

Consult the project map to see the location of the planned substation and line routes on Google Earth.

Biophysical and human environment

The biophysical and human environment map below shows the elements that could be impacted by the project.

Biophysical and human environment map for Patriotes project (in French only) [PDF 1 Mb]

Project components

Hydro-Québec plans to build the new Patriotes substation in Saint-Eustache’s industrial sector. In the first phase, the substation will include three high-to-medium-voltage transformers (315/25 kV) in order to meet customers’ needs. Another transformer may eventually be added to respond to changes to development in the regional county municipality of Deux-Montagnes.

Visual simulation of the proposed Patriotes substation

A new 315-Kv supply line will connect the planned substation to the existing 315-kV line located north of Boulevard Arthur-Sauvé. The new support structures will be four-legged lattice towers or reduced-footprint lattice towers, which reduce the line’s impact on farmland.

Standard tower types and right-of-way widths of a 315-kV transmission line

Hydro-Québec then set out line routes and locations for the substations based on the following criteria.

Substation and line

  • Avoid the most environmentally sensitive areas: the built environment and residential developments, sugar bushes, land reserved for horticulture and specialized crops, wetlands and erosion zones.


  • Build the substation as close to the load centre as possible.
  • Avoid protected agricultural land.


  • Trace routes that do not require the relocation of homes or important farm buildings.
  • Determine the shortest possible route to reduce construction costs and the number of elements and spaces that may be affected by the project.
  • Limit landscape impacts.
  • Respect property and lot boundaries whenever possible.
  • Limit the number of landowners affected by the project.

Selected substation site and line route

Map of the selected substation site and line route for the Patriotes project

Selected substation site

Hydro-Québec plans to build the new Patriotes substation on Boulevard Albert-Mondou, in Saint-Eustache’s industrial area, an environment compatible with this type of equipment.

The selected site is located near the ADESA Montreal corporation premises and south of the right-of-way for the Réseau de transport métropolitain (RTM) railway.

Initially, the substation will be equipped with three transformers that will lower the voltage from 315 to 25 kV and supply 19 25-kV distribution feeder bays. As demand grows, another transformer could be added to supply a total of 28 distribution feeder bays.

Plantings and an architectural fence are planned in front of the substation to help integrate the facility into its environment.

Selected line route

Optimization of route B

Hydro-Québec conducted studies to optimize route B in response to the concerns expressed by the community during the consultation phase. A number of improvements were made to the initial route.

To replace an existing tower rather than add one, Hydro-Québec moved the connection point for variant B west of the Autodrome Saint-Eustache. This change also reduces the clearing of deciduous forest by 50% compared to the initial route B.

Hydro-Québec will be purchasing two properties on Boulevard Arthur-Sauvé and Chemin de la Rivière Nord to keep the future line far from neighboring homes and ensure that the route is as linear as possible. An increased proportion of reduced-footprint towers will be used so that the line will better integrate into the landscape.

Improvements to the alignment and distribution of towers will be made to help reduce the visual impact of the line for residents living on the roads that run along the Rivière du Chêne. In addition, selective clearing will be carried out in the ecological corridor of the Rivière du Chêne to preserve as much vegetation as possible.

Selected route

The selected route is 5-km long and located entirely within the boundaries of Saint-Eustache’s agricultural zone. It runs along the west side of the Autodrome Saint-Eustache for over 1 km and through large-scale crop fields for 4.1 km. It crosses a maple stand for 270 m and another forest for 210 m.

Project schedule

Public participation process Fall 2015 – summer 2017
Filing of environmental impact statement Fall 2017
Permitting Fall 2017 – winter 2018-2019
Substation construction Spring 2019 – summer 2020
Line construction Fall 2019 – summer 2020
Commissioning Summer 2020

Before construction begins, a project news bulletin will be published for the local community with detailed information on the project.

We will see to it that surrounding spaces and roads are protected during construction work and restored after the project is finished. During construction work, measures will be taken to reduce nuisances such as noise and heavy vehicle traffic.