Over the past few months, Hydro-Québec has carried out technical and environmental studies and spoken with community representatives, environmental groups, Indigenous communities, property owners potentially affected by the project, and residents of the study area. Throughout the many discussions held, the project and the line routes under study were presented and concerns were taken into consideration. The public consultation process resulted in a better project and one that is tailored to the realities of the host communities.
The line route includes a 56.1-km (34.9 miles) underground segment and a 1.6-km (1 mile) underwater segment. For most of its route, the line is located in public rights-of-way. In total, eight municipalities are affected by the project: La Prairie, Saint-Philippe, Saint-Jacques-le-Mineur, Saint-Édouard, Saint-Patrice-de-Sherrington, Saint-Cyprien-de-Napierville, Saint-Bernard-de-Lacolle and Lacolle.
The route runs along Highway 15 for 24 km (15 miles) and along the rights-of-way of provincial and municipal roads for 29 km (18 miles). From Hertel substation in La Prairie, the route runs along Rang Saint-Raphaël, Rang Saint-Claude, Montée Signer, Rang Saint-Marc, Route Édouard-VII and Montée Saint-Jacques, in the municipalities of Saint-Philippe and Saint-Jacques-le-Mineur. It runs through Hydro-Québec property and farmland over a little more than 3 km (1.9 miles). The remainder of the line runs along the Ruisseau Fairbanks to the Rivière Richelieu, where the interconnection point with the U.S. power system is located.
In September 2021, New York State authorities selected the Champlain Hudson Power Express project and its connection to the Hertel–New York interconnection line to deliver hydropower into the heart of New York City. This 1,250-megawatt (MW) influx of clean power, enough to supply 1 million homes, will start displacing fossil generation as soon as 2025 in the NYC region, which is today over 85% reliant on fossil fuel-based electricity. The project will help reduce GHG emissions in northeastern North America by the equivalent of about 3.9 million tonnes of CO2 every year.
Once commissioned, the Québec line will operate as a partnership between Hydro-Québec and the Mohawk Council of Kahnawá:ke, which will thereby benefit from economic spinoffs for a 40-year period.