What is Hwy H2O?

Hwy H2O is a 3,700-kilometre (2,400 mile) marine corridor between Canada and the United States. Comprised of the St. Lawrence River, St. Lawrence Seaway and the Great Lakes, Hwy H2O is a vital transportation artery that enables domestic and international trade, and offers unique access directly into North America’s commercial, industrial and agricultural heartland.

The unfettered movement of vessels along the waterway ensures that cargo arrives reliably at its destination on time.

In addition to its crucial transportation function, the waterway is a popular recreational area enjoyed by millions and a natural resource that must be protected. Hwy H2O partners understand that the waterway is a shared resource that must continue to serve all of its distinct roles in perpetuity.

Hwy H2O by the numbers

the value of the more than 3 billion tonnes of cargo carried along the St. Lawrence Seaway since its opening
the number of direct and indirect jobs related to the waterway
saved by cargo shippers in transportation costs each year
the longest navigation season on record, set in 2017

1 – the number of litres of fuel required to move one tonne of freight 240 kilometres by ship

Who is behind Hwy H2O?

Hwy H2O is an alliance of transportation stakeholders, actively promoting marine transportation on the Great Lakes / Seaway System. The St. Lawrence Seaway Management Corporation and the Great Lakes St. Lawrence Seaway Development Corporation are sponsors of the program. Port Partners and Members include commercial entities such as ports and transportation associated enterprises, like stevedores, carriers and municipalities.

What are the Hwy H2O objectives?

Initiated in 2003, Hwy H2O works to identify and promote key opportunities for the marine mode on the Great Lakes St. Lawrence Seaway System. The St. Lawrence Seaway offers unparalleled capacity to increase cargo volumes within its existing infrastructure. Hwy H2O is committed to raising awareness of the Seaway’s untapped potential for meeting current and future transportation challenges in an economically sound and environmentally responsible manner.

What is short sea shipping and how does it work?

Short sea shipping refers to the movement of cargo by water between points situated within relatively close proximity to one another. This may include domestic as well as international maritime transport along coastlines or within lakes and inland water systems.

The application of short sea shipping along Hwy H2O is based on the reality that most container vessels are too large to fit into the Seaway. Container vessels currently under construction are even larger yet, bringing about a future where only a limited number of coastal hub ports will be able to accommodate these enormous ships.

Accordingly, part of our vision for short sea shipping along Hwy H2O sees large ocean-going container vessels docking at coastal hob ports, such as Halifax, Nova Scotia where they would transfer their cargo to smaller “feeder” vessels, which would deliver the containers to a Seaway / Great Lakes port near their final destination.

It is important to note, “feedering” presents the added environmental benefit of further mitigating the risk of introducing exotic or invasive species to the Great Lakes St. Lawrence Seaway System. Since feeder vessels would only transit routes within the waters of our own continental boundaries, they will not be carrying ballast water from overseas destinations. This approach can mitigate the potential introduction of aquatic invasive species to the Great Lakes / Seaway System via ballast water.

Other important benefits associated with short sea shipping along Hwy H2O include the alleviation of congested road and rail arteries and the reduction of greenhouse gas emissions.

What are the benefits of moving cargo by the marine mode along the Seaway?

Highway H2O allows cargo to bypass border bottlenecks on railways and roads. The waterway’s available capacity and unrestricted movement of cargo, in combination with the marine models unmatched safety and fuel efficiency make moving cargo along Hwy H2O attractive to shippers, their customers and the businesses and communities who depend on the reliable delivery of their cargo.

What is being done to ensure that the issue of aquatic invasive species does not escalate?

Hwy H2O partners are committed to ensuring the waterway is maintained and developed in a manner that is environmentally and ecologically responsible.

For an update on the latest initiatives, please consult the St. Lawrence Seaway’s ballast water page at:

Are there environmental benefits associated with utilizing marine transport?

Transporting goods by water delivers substantial environmental benefits, including:

  • Energy efficiency – On a single litre (about a 1/4 U.S. gallon) of fuel, one tonne of freight can travel 240 km by ship, compared with less than 100 km by train and less than 30 km by truck
  • Reduced emissions –  Ships only emit one tenth the greenhouse gas emissions that trucks produce and half that of trains
  • Increased safety – The marine mode is the safest mode of domestic and international freight transportation, thus reducing the likelihood of environmental harm caused by accidents and spills
  • Minimal noise – Marine transportation generates very little noise, when compared to other forms of transport
  • Mitigated need for future highway and rail line infrastructure investment – Utilizing Hwy H2O decreases the need for new roadways and rail lines, the creation of which negatively impact quality of life, communities and the ecosystem

Every mode of transportation creates an environmental footprint, and it’s important to note that the elimination of one maximum size Seaway vessel would require the addition of 963 truckloads on our highways, or the addition of 301 railcars to the rail system. Any addition of trucks or rail cars to our roads and railways would only serve to exacerbate current issues of congestion faced by those modes of transport and associated environmental effects.