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Tacoma Harbor Navigation Improvement Study


The purpose of the Tacoma Harbor Navigation Improvement study is to investigate potential navigation improvements to the Blair and Sitcum Waterways in the Port of Tacoma to provide transportation cost savings (increased economic efficiencies) for larger vessels calling at the Port.

Deepening these waterways may result in cost and time savings, potentially lowering project operations and maintenance costs, as well as potentially allowing for the removal of draft restrictions for certain vessels.

The Port of Tacoma is a rapidly expanding major port, ranking as the 28th largest U.S. port in terms of total tonnage, and the 4th largest container gateway when combined with the Port of Seattle. In the past decade, ships calling at the Port of Tacoma have increased in size and draft at a dramatic pace. The Blair Waterway is currently authorized to -51 feet. The Sitcum Waterway is not a federally authorized channel. The larger vessels have draft requirements deeper than -51 feet when fully laden, and therefore face tidal delays and other transportation inefficiencies when arriving and departing the waterways.

The General Investigation Study will analyze alternatives associated with opportunities for channel deepening. Opportunities may exist to increase safety while improving efficiency of vessels transiting Tacoma Harbor’s Blair and Sitcum Waterways. By being able to more fully load vessels, transportation costs will potentially decrease, ultimately leading to more cost-efficient transportation system as well as improved capacity for increased trade and lower priced goods.

The feasibility study will determine whether there is a federal interest in participating in a cost-shared modification of the existing Tacoma Harbor project in the interest of navigation improvements and water resource development opportunities.


The U.S. Army Corps of Engineers and The Northwest Seaport Alliance signed a feasibility cost-share study agreement August 21, 2018, that will allow for a deepening study of the Port of Tacoma waterways.