Coastal erosion is the natural process of sediment removed by waves over time. The continuous removal of sediment by waves causes shorelines to recede further inland, jeopardizing beaches and the safety of seaside communities. Manson participates in efforts to revitalize shorelines through a process called beach nourishment.
Beach nourishment is a process that involves the transportation of sand and the filling and replacement of lost material along shorelines. The benefits of beach nourishment directly affect the beach, local economy, and most importantly, provide safety to coastal properties and infrastructure.
These projects start with coastal engineers, who spend months--and sometimes years--on the design and planning phase. These experts understand the complexity of coastlines, recognizing the different characteristics each site presents. This phase of work can be challenging for engineers as the topography of each beach varies. Engineers also have to consider the unpredictability of wave and storm conditions. They use computer-generated models to calculate the behavior of a beach and the types of storms that might affect the area. Once these experts understand the patterns of a beach, they work with a third party to search for a borrow site. Borrow sites are locations that are used to source replacement material for marine projects.
Sourcing material at a borrow site takes time and extensive research to ensure the quantity requirement and sand are suitable for eroded shores. The replacement sand should resemble the previous material in terms of size, color, and texture. Engineering teams recognize this as an important feature for the nourishment process and for the performance of the project.
Engineers must take several important factors into account during this project stage, including cost, removal, transportation, and grade of material. Borrow sites can be a good resource for multiple beach nourishment projects, but material in that area can diminish over time. When this happens, engineers explore other sites to collect material from. The location of a borrow site can vary from harbors, channels, offshore deposits, or dry land.
Once the borrow source is identified, engineers transition from the design and planning phase to finding a contractor with proven experience in beach nourishment as well as the necessary equipment to complete the job.
Earlier this summer, Manson was selected by the U.S. Army Corps of Engineers (USACE) as the primary contractor for the Galveston Harbor and Channel, HSC, Galveston Entrance and Bolivar to Redfish Hopper Dredging project which included the nourishment of Babe’s Beach in Galveston, Texas.
A popular beachfront attraction for both locals and tourists, Babe’s Beach is visited by thousands of people daily. Due to aggressive coastal erosion of the area, Babe’s Beach undergoes maintenance every couple of years. The beach is a driving factor for Galveston’s local economy, with a collection of restaurants and shops within miles of the recreational front. In a collaborative effort, the USACE, City of Galveston, Texas General Land Office, and the Gulf RESTORE Act generated $12 million dollars of funding to maintain and protect Babe’s Beach.
With much of the project’s design and planning sections completed by the USACE, Manson was brought on for the dredging and construction phase. Manson mobilized the hopper dredge BAYPORT, derrick barges, and rented tugboats for the offshore work. Shore equipment included bull dozers, a loader, and beach pipeline connected to the floating and submerged pipelines.
“With the site and material specifications already set by the USACE, our crews and equipment are brought in to do the heavy lifting,” says Madeline Brisson, Manson Field Engineer.
About 7,000 ft. of submerged, floating, and beach pipeline is being used to pump and fill Babe’s Beach. Dredge crews are dredging 2.8 miles out on the Houston-Galveston Ship Channel, taking the BAYPORT two hours to sail to and from the borrow site where the pumping takes place. With shore crews working round the clock to grade material throughout the area, 950,000 cubic yards of sand will be pumped onto the beach.
Three months into the nourishment of Babe’s Beach, the project is on pace to be completed next month. Crews are dredging the last sections of the ship channel and pumping the last of the material to shore, where teams are waiting to spread the sand. Manson will deliver the project just in time for visitors to enjoy Babe’s Beach before temperatures drop for the winter.
“It’s been really cool seeing the positive impact this job has had on the community and bringing back the beach for residents and tourists,” Madeline explains. “Most dredging jobs aren’t seen by the public, but, with this job, it’s nice to know we can show the public that we are making a difference.”
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