Posted on January 13, 2025
MOBILE, Ala. – Since 2020, the U.S. Army Corps of Engineers, Mobile District Mobile Harbor Project, and its partners have sought to deepen and widen the Mobile Harbor Channel by five feet from the Gulf of Mexico through Mobile Bay and into Mobile Harbor. The entrance channel through the Gulf is being deepened from 45 feet to 50 feet.
Additionally, the southern portion of the Bay channel is being widened by 100 feet for three miles to accommodate two-way traffic. Two bends are being eased to facilitate more efficient navigation from the Gulf into Mobile Bay.
The process of deepening and widening requires dredging. Thus, the question becomes what is done with the dredged material from Mobile Bay and Mobile Harbor.
USACE regularly collaborates with federal partners, the National Oceanic and Atmospheric Administration and the U.S. Fish and Wildlife Service, to protect the environment, fish habitats, and species.
The District actively monitors dredging to ensure compliance and continues to work with jurisdictional agencies to protect Bay resources. Multiple methods are employed during dredging operations to ensure compliance with environmental laws and regulations.
For example, turbidity measurements are taken daily per contract specifications and submitted to the Corps. In accordance with the Alabama Department of Environmental Management 401 Water Quality Certification, if the turbidity threshold is exceeded (i.e. if the discharge in the mixing zone is greater than 50 Nephelometric Turbidity units above the background), the contractor is required to adjust operations.
The Mobile Harbor Project remains in compliance with all applicable federal and state regulations.
The District completed the NEPA process in 2019 and 2023 for the Mobile Harbor deepening project and in 2014 for the maintenance material’s in-bay placement, commonly referred to as thin layer placement.
The environmental and dredging industries widely accept thin-layer placement as a best practice. This method re-introduces sediment to the natural sediment transport system instead of removing it.
Thin layer placement in Mobile Bay was specifically studied by collecting data during and after an emergency placement operation. This data was used to develop and calibrate models predicting how Mobile Bay’s sediment behaves. These model results were shared with environmental and resource agencies for review and consultation as part of the NEPA process.
The Mobile Harbor Project is being constructed in seven phases. Three phases are already complete, three are currently under construction, and the final phase was awarded in late summer 2024.
Construction is projected to be completed in the summer of 2025, and it is currently on schedule and within budget.
For updates and additional information about the project, visit the website: https://www.sam.usace.army.mil/Missions/Program-and-Project-Management/Civil-Projects/Mobile-Harbor-Project/
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With an area of operation across Alabama, Mississippi, Georgia, and northern Florida, and a vast military region that includes operations across Central and South America, the Mobile District’s award- winning teams of engineering, construction, regulatory and emergency management professionals are nationally recognized for their leadership in delivery of the U.S. Army Corps of Engineers’ civil works and military programs missions to the Nation.
