The Columbia River, which partially establishes the natural border between the states of Washington and Oregon, is a vital waterway that serves as passage for ships hauling 50 million tons of cargo worth $21 billion annually and supports hydroelectric dams, the local fishing industry, and irrigation for farming. Because of severe shoaling, the Lower Columbia River (LCR) and Mouth of the Columbia River (MCR) require annual maintenance dredging to maintain water depth.
In 2023, Manson was awarded the FY23 West Coast Hopper Maintenance Dredging project to clear sediment in the LCR and MCR for the United States Army Corps of Engineers (USACE) Portland District.
“USACE relies on Manson to bolster their navigation mission with our dredges to remove material out of the river,” says Project Manager Alex Merlo. “The project is short but requires a competent contractor to complete the work with knowledge and efficiency.”
Dredging the Columbia is familiar territory for Manson, which has successfully completed West Coast Hopper Maintenance Dredging five times since 2014. This year, the contract also included the potential for optional beach renourishment work in addition to dredging the Columbia River—options that USACE decided to exercise this season.
“The project also included beach nourishment work at San Clemente, Solana, and Encinitas beaches near San Diego, CA,” explains Lead Engineer Taylor McRae, “which was important work for Manson, USACE, and the beachside communities in Southern California.”
Sailing to the Columbia River Finishing several months of dredging and beach nourishment on the Fort Pierce Shore Protection and Jacksonville Harbor Maintenance projects in Florida, the hopper dredge BAYPORT made its way to Manson’s Jacksonville yard to prepare the vessel for the long voyage to the Pacific Northwest.
“The BAYPORT crew conducted preparatory work to get the BAYPORT ready to sail through the Panama Canal,” Alex says. “Getting the dredge together for a project is one thing, but traveling through the canal takes a coordinated effort between the crew, project staff, and shipping agents who help guide us through the waterway.”
A critical passageway for global maritime transportation, the Panama Canal links the Atlantic and Pacific Oceans. It is navigated by more than 13,000 ships a year, according to the Council on Foreign Relations.
Traversing the Panama Canal can be challenging, with dozens of ships waiting to move along, but the project team was one step ahead in avoiding the traffic jam in June 2023.
“We communicated with Panama Canal agents to fast-track the voyage and received priority,” says Dredging Project Engineer Ben Herbay. “It took about a month for the BAYPORT to sail around Florida, down through the canal, temporarily stopping in San Diego to meet customs requirements, and finally reaching the LCR near Longview, WA.”
Dredging at the LCR
Due to a heavy shoaling season, USACE modified the dredging contract, requesting the BAYPORT to arrive in July 2023, a month ahead of schedule.
The shoaling season for the Columbia River typically occurs in the summertime, after the snow melts —introducing an intense flow of water up and down the river. The seasonal water flow presents draft restrictions for larger ships traveling the waterway, which can cause serious economic impacts on domestic and international communities.
“Dredge work on the river can get busy because our main objective on this project is to keep the shipping traffic productive and remove material from identified hotspots,” Ben says. “It can be challenging to navigate the dredge to the different hotspots because of their scattered locations, but consistent communication between the project team and BAYPORT crew has produced successful results.”
Over the summer months, the BAYPORT crew dredged approximately 1.3 million cubic yards of material from the LCR, placing the material at designated disposal sites.
“The disposal capacity aspect of this job was challenging because the crew had to be precise with dredging because of the limited disposal areas in the river,” Ben explains. “The crew had to manage channel cleanup without overfilling the disposal sites and not digging up extra material. This is difficult to do, but the BAYPORT crew are experts.
Dredging at the MCR
After completing dredging in the LCR, the project team and BAYPORT quickly mobilized to the MCR, several miles down the waterway.
Due to the depth of the river, the MCR is a unique environment to dredge. To adapt to the challenge, the team added extensions to increase the reach of the hopper’s drag arms. Dredging on the MCR takes strategic communication and planning to move material to acceptable sites approved by USACE, which provides information to the project team regarding disposal training and how to repurpose the material to improve the waterway and support the existing jetties on the waterway—specifically the North Jetty near East Sand Island, OR. Disposal training is the art of disposing dredged material in a location such that the water’s natural flow will push the sediment to the desired location. By strategically placing the material in a specific location, via opening up the hopper to dispose of the material, that material helps the nearby jetties because it naturally migrates to those particular parts of the river. This is one of the many forms that beneficial reuse of material can take.
“The disposal training from USACE explains the process of dredging the mouth of the Columbia and reinforces the purpose of the project,” Ben says.
With the information given, the project team identified open-water disposal sites and developed a cohesive plan to complete the work.
The BAYPORT dredged approximately 1.3 million cubic yards of material, placing it at the sandbar Peacock Spit. The river’s natural flow migrates the material toward the North Jetty to help restore erosion in many parts of the MCR.
By accelerating the construction schedule, the BAYPORT crew wrapped up dredge operations at the MCR in October 2023. The BAYPORT then sailed toward Coos Bay, OR, where it underwent maintenance and preparations for additional beach renourishment in Southern California.
Restoring SoCal Beaches
Due to severe storms and coastal erosion, the San Clemente beachfront has decreased drastically over time, causing a significant impact on the beachside community and a lack of protection from waves. The beach nourishment project produced a new 50-ftwide sand berm, which supports the City of San Clemente’s Sand Nourishment Cycle every six years—the first replenishment project in the city’s history.
Starting in December 2023, the BAYPORT crew dredged and transported 24,000 cubic yards of material via pipeline from a borrow site south of San Clemente, but the project team halted operations when they realized the material being pumped was unacceptable.
“The material from the borrow site was more rock and shell than sand,” Taylor says. “What we were pumping on the beach was the opposite of beach renourishment.”
Weighing on a decision that would change the project schedule at San Clemente, Manson and the City of San Clemente decided to temporarily suspend operations until a new borrow site could be determined.
While USACE shifted its attention to finding a new borrow site, the BAYPORT pulled anchors and headed 40 miles south to Solana Beach to jumpstart the next phase of beach renourishment in January 2024.
With the help of Manson’s beachside personnel, the BAYPORT pumped more than 700,000 cubic yards of material onto Solana Beach. Led by Beach Foremen Freddie Harriel and Barry Jones, the dozer and excavator team spread the fresh material to widen the beachfront to 150 ft in just two months.
After opening Solana Beach to locals and tourists in mid-March 2024, Manson continued beach nourishment five miles north at Encinitas Beach.
The geography at Encinitas was very different from that of Solana, as the rock-infested area proved dangerous for residents and people looking to enjoy the natural recreational space. “Encinitas was more challenging because there was very little beach to work with,” Ben says. The beachside had a very narrow berm (a flat portion of land), which gave our landside crew less room to work and store equipment.”
Freddie, Chuck, and Barry’s experience and knowledge helped the beach crew work efficiently within the unique site conditions. Crews spread 340,000 cubic yards of material pumped from the BAYPORT and opened the beach, now 50 ft wider, by mid-April.
With two phases of beach renourishment completed, USACE informed the BAYPORT crew they could head back to San Clemente to finish the work they started. Given a new borrow site to work with, the BAYPORT delivered the first load of sand in late April. Crews are working around the clock, seven days a week, to place sand and replenish San Clemente by May 2024.
The local communities are glad for their improved coastlines and for an end to the inevitable noise and busy activity that comes with building out the new beachfront.
“Our funny quote to each other is, ‘Hate us while we are here but love us when we are gone,’” Ben jokes. “Nobody likes having their beach time interrupted, but we receive this huge surge of support whenever we finish. We’ve had multiple people tell us about how Manson’s work is great for the community.”
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