Using optimization strategies to prioritize and schedule dredging operations

U.S. Army Engineer Research and Development Center
Published July 19, 2022
A mechanical dredge moves dredged material from Charleston Harbor to a barge.

A mechanical dredge moves dredged material from Charleston Harbor to a barge. Research at the U.S. Army Engineer Research and Development Center is applying the power of artificial intelligence to development more efficient patterns for dredging operations within the United States.

Researchers with the U.S. Army Corps of Engineers (USACE) have developed dredging optimization models using artificial intelligence and operations research methods to help prioritize and schedule dredging operations across the enterprise.


Dredging is the largest individual item in the USACE civil works budget, and traditionally there has not been a rigorously quantitative nor repeatable process for determining the most efficient and effective way to conduct maintenance dredging across hundreds of projects nationwide. However, two separate models, the Dredge Project Selection Optimization model and the Dredge Fleet Scheduling Optimization model aim to change all that. 


“These models are not about dredging operations,” Dr. Ned Mitchell, a research civil engineer with the U.S. Army Engineer Research and Development Center, said. “This is not about how to dredge. It is more about how to manage the dredging program, both from a budgetary standpoint and a scheduling standpoint.”


The USACE spends around $1.5 billion each year on dredging in hundreds of navigation projects across the country. A typical dredging project goes through several phases, including project planning, bidding, contract award, dredging, placement, inspection and project completion.


“These models can give us the ability to answer which locations are most critical from a nationwide perspective,” Mitchell said. “How extensively do we need to dredge them and how frequently? What is the sequencing of the work, and what is the best regionalization of contracts to increase the number of competitive bids?”


The USACE is responsible for maintaining and improving nearly 12,000 miles of shallow-draft inland and intracoastal waterways, 13,000 miles of deep-draft coastal channels and 400 ports, harbors and turning basins throughout the U.S. In recent years, more than 200 million cubic meters of material were dredged from federally constructed and maintained navigation channels.


“Adoption of these strategies will allow for a more cost-effective mission delivery and a more resilient execution strategy,” Mitchell said. “By saving $100 million or more per year through the solutions that these models produce, we can apply needed resources to smaller projects that historically haven’t been able to get funded. We’re able to do more with the same amount of money and reduce the longstanding maintenance backlog. It also gives us the ability to adjust and adapt to the unexpected through more efficient use of the industry dredging fleet.”


Additionally, USACE can reduce the mobilization, or travel cost, that dredges incur between projects. “If the dredge can now travel 50 miles between project sites instead of 200 miles because we’ve been smart with how we’ve coordinated and sequenced the groupings, then we are being more cost-effective with taxpayer dollars,” Mitchell said.


With the increase in size of container ships and growth in shipping, it is expected that dredging amounts will continue to be a necessary measure to facilitate navigation at American ports, harbors and waterways.


“Our objectives are to operationalize these capabilities,” Mitchell said. “To move them out of the research and development space and into a cloud-based computing environment living at a district operations center where anyone in USACE can access them on demand. On the R&D side, we will continue to make refinements, pushing for improvements and next generation enhancements, but these baseline capabilities can be realized now.”