Montreal South Bypass (AutoRoute 30)

What to See & Do on the Montreal South Bypass?

To quickly get either east of or west of Montreal, without going through Montreal and getting stuck in the traffic or in construction (2023-2025). This toll-route is a great time-saver.

You get to see Montreal’s vibrant South Shore communities, but the highlight of this route is TWO bridge crossings over the St Lawrence River and Sta Lawrence, plus a tunnel underneath a canal just to the north

Quebec Itinerary - Montreal South Bypass

Route Access

From the West

  1. from AutoRoute 40 (a continuation of Ontario’s 417 south from Ottawa) at Exit 32 to Sorel-Tracy / Toronto, (about at km 150 of that itinerary) OR
  2. from AutoRoute 20 (a continuation of Ontario’s 401 from Toronto) take exit 29 to Sorel-Tracy Ottawa/Gatineau (about km 239 of that Itinerary). After exiting A-20, stay in the RIGHT LANE.

 From the East

Access this route from the east on AutoRoute 20 from Quebec City/Levis at Exit 98 (at km 215 of that itinerary)

Highway 30 toll plaza-closeup
Highway 30 toll plaza-closeup

AutoRoute 30 Description

North St Lawrence (Ontario Access)

Accessing this Montreal South Bypass from the west, you either catch if from the A40 (from Ontario 417) before the Île aux Tourtes Bridge into Montreal or from the A20 (from Ontario 401) before the Galipeault Bridge crossing the Lake of Two Mountains or Lac deux Montagnesinto Montreal (see Montreal Bridges article). From these interchanges, the highway heads south across a mix of farmland and Montreal suburb to the toll booths (in both directions).

South of the toll plaza, you cross the St Lawrence TWICE. The two crossings over the St. Lawrence required the Canadian Parliament to pass laws approving their construction.

Crossing the St Lawrence

The north channel has significant dams and rapids, and is crossed by the 2.5 kilometres long Madeleine-Parent Bridge, which crosses the Soulanges Canal of the seaway on the north side and then one channel of the St Lawrence River. there are dams and rapids on both sides of the highway.

Les Cedres Tunnel under C anal de Soulanges on 30 South
Les Cedres Tunnel under C anal de Soulanges on 30 South

Montreal South Shore Communities

After the Autoroute bends east, it crosses the south the Beauharnois Bridge across the St Lawrence Seaway (the Beauharnois Canal is on the north side) and then the St Lawrence River. The Beauharnois Bridge is a 2.5-kilometres long structure, clearing the navigation channel by 38.5 metres. The Beauharnois Dam is east of the bridge is was built as part of the St Lawrence Seaway project in the late 1950s. The Beauharnois Dam is 24 m (60 ft) high and has 36 turbines generating 1.9 megawatts of power for the Montreal area. Tours of the dam are available

After passing the community of Beauharnois, you see the Îles de la Paix National Wildlife Area on islands in the middle of the St Lawrence. Then you pass the South Shor bedroom communities of Chateauguay, Candiac (and a junction with A-15 to the US border), and Brossard (and a junction with A-10 from Montreal to the Eastern Townships).

Finally, at Boucherville, you reconnect to the A-20 Trans-Canada Highway east to Quebec City (you join that itinerary at km 36).


Route History

Autoroute 30 (A-30) is also known as the Autoroute de l’Acier (which translated into English is “Steel Freeway”).  The planning and construction of the A-30 goes back to the early days of autoroute construction boom in the 1960s.

It was originally called Highway 3,  and was designed to replace Route 132 (which is a relaxed 2-lane road that connects small towns and villages along St Lawrence to — and around — the Gaspe Peninsula) as the main artery for communities along the Montreal South Shore of the St. Lawrence River.

The A-30 was originally intended to begin at the U.S. border at Dundee and end at Saint-Pierre-les-Becquets (in Centre-du-Québec).[4] In the late 1970s an eight-year moratorium on new autoroute construction in favour of public transport by the Parti Québécois prevented implementation of that plan.

The first completed section of Autoroute 30 in 1968, started at Sorel-Tracy south to Route 116 (which was then called Highway 9). The A-30 was extended further south to an interchange with Autoroute 10 in Brossard by 1985 (to coonnect Montreal to the Eastern Townships)  and to Autoroute 15 in Candiac by 1996  (which connected Monteral to the US border, and I-87 to Plattsburg and Albany, New York).

By 2006, the growing road congestion in and around Montreal led to the announcement of a federal-provincial partnership to complete A-30 as southwestern bypass ring road.

The initial expection was the Châteauguay to Vaudreuil-Dorion section was to be tolled, though in 2009 it was decided to collect tolls on a new bridge built over the  St. Lawrence west of Beauharnois. A-30 was extended north of the St. Lawrence River with interchanges with A-20 (connecting Ontario’s 401 to Montreal)  and with A-40 (connecting to Ontario’s 417 to/from Ottawa).

The full Autoroute 30 was opened to traffic  in late 2012, enabling motorists travelling the Quebec City–Windsor Corridor to bypass the island of Montreal’s  traffic and congestion (saving 45 minutes in travel time, more in rush hours).

Search Listings along this Itinerary

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Highway 30 - Pont Serge-Marcil over the St Lawrence
Highway 30 - Pont Serge-Marcil over the St Lawrence

Autoroute 30 Montreal South Bypass Itinerary Segment Map