Dredging projects in Tacoma and Seattle will keep the cargo gateway competitive

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Take a boat ride with Tony Warfield and you’ll glimpse the future. 

Warfield is a Senior Project Manager in the Port of Tacoma’s environmental department 

On a trip into the Blair Waterway, home to three international container terminals on property managed by The Northwest Seaport Alliance (NWSA), Warfield explained that across the industry, ships are being built bigger. 

“A ship calling here five years from now may well be 30 percent larger in terms of volume,” Warfield said. “They'll need another six feet.”  

Because larger ships require more water depth, the Port of Tacoma is working with the U.S. Army Corps of Engineers (USACE) to deepen the Blair Waterway from 51 to 57 feet. 

“A thriving working waterfront requires critical infrastructure investments,” said Port of Tacoma Commission President and NWSA Co-Chair Deanna Keller. “The ability to accommodate larger ships will help to keep our gateway competitive in the marine cargo business.” 

On December 12, the Port and the USACE signed a design agreement to deepen the Blair’s navigation channel. 

Earlier this year, the USACE and Port of Seattle signed a similar agreement to deepen the West Waterway. 

Together, the deepening programs in Tacoma and Seattle will ensure the entire gateway is big-ship ready. 

“This gateway deepening gives the ultra-large vessels that are now common at ports around the world unrestricted access to Terminal 5 and also ensures cargo and job opportunities remain strong in our harbor for decades to come,stated Port of Seattle Commission President and NWSA Co-Chair Sam Cho. 

Container ship capacity is measured in what are called twenty-foot equivalent units, or TEU’s. 

Previously, ships carried a few thousand containers. 

Now, ships calling in Tacoma and Seattle often have a capacity of 12,000-15,000 TEU’s.  

To remain competitive in the international container business, the NWSA must be able to handle Super-Post Panamax ships with a capacity of 18,000+ TEUs. 

It’s a pretty remarkable ratio. For every dollar spent on the deepening project, we anticipate $10 in economic benefit,” said USACE-Seattle District Commander Col. Kathryn Sanborn. 

On the Blair Waterway, the USACE and Port of Tacoma are beginning design work for dredging the navigation channel.  

The Port and NWSA are also starting to design deeper berth areas at the terminals in the Blair, which will involve extensive underwater reinforcement. 

Dredging is expected to begin in 2025 and take several years, as the project moves from north to south along the waterway. 

To protect fish, sediment removal will only happen between July and February when juvenile salmon are unlikely to be present. 

Working with the USACE, the Port is considering placing clean dredged material to create a site called the East Commencement Habitat Opportunity, or ECHO. 

Since the early 2000s, the Port has been looking to build a mitigation and salmon habitat restoration site in eastern Commencement Bay.  

This 20-plus acre site is one of the last best places in the bay for nearshore restoration.  

The project is just offshore from Marine View Drive and is also expected to mitigate erosion that threatens the long-term viability of the roadway. 

 “Put a berm here, break the energy from the fall storms,” Warfield explained on the boat tour. 

The Port of Tacoma hopes a deeper Blair Waterway can be a win for fish, and for the economic benefits from the big ships of the future.