US flag Great Lakes St. Lawrence Seaway Development Corporation

Great Lakes St. Lawrence Seaway Development Corporation is a wholly owned government corporation created by statute May 13, 1954, to construct, operate and maintain that part of the St. Lawrence Seaway between the Port of Montreal and Lake Erie, within the territorial limits of the United States. Trade development functions aim to enhance Great Lakes/St. Lawrence Seaway System utilization without respect to territorial or geographic limits.

The mission of the Corporation is to serve the U.S. intermodal and international transportation system by improving the operation and maintenance of a safe, reliable, efficient, and environmentally responsible deep-draft waterway, in cooperation with its Canadian counterpart. The GLS also encourages the development of trade through the Great Lakes Seaway System, which contributes to the comprehensive economic and environmental development of the entire Great Lakes region.

The GLS headquarters staff offices are located in Washington, D.C. Operations are located at the two U.S. Seaway locks (Eisenhower and Snell) in Massena, N.Y.

Formerly the Saint Lawrence Seaway Development Corporation (SLSDC), the GLS was legally renamed as part of the 2021 Consolidated Appropriations Act (Section 512 of Division AA of P.L. 116-260), signed into law on December 27, 2020.

For more information, visit the GLS Web site at or visit the GLS Facebook page at Facebook

GSL Mission Statement

Our mission is to serve the marine transportation industries by providing a safe, secure, reliable, efficient, and competitive deep draft international waterway, in cooperation with the Canadian St. Lawrence Seaway Management Corporation.

Vision Statement

Great Lakes St. Lawrence Seaway Development Corporation will be a model federal agency, leading the Great Lakes Seaway System as the safest and most efficient, competitive, technologically advanced, and environmentally responsible marine transportation system in the world.

Organizational Core Values:

  • Service
  • Leadership
  • Stewardship
  • Dependability
  • Commitment

Annual Reports