Miami Harbor Dredging Project Proves Successful

The U.S Army Corps of Engineers, Jacksonville District, has announced the official construction completion on the Miami Harbor Deepening and Widening Project, the first major port deepening to a 50-feet depth in the southeastern United States.

Along with deepening, which was finished in September, mitigation construction is also completed. Recent monitoring shows the mitigation features are functioning successfully.

We are pleased at the success of the mitigation features,” said the Corps’ Jacksonville District Commander, Col. Jason A. Kirk. “The features include nearly 17 acres of seagrass and 12 acres of artificial reef.”

Recent surveys, conducted a year after construction of the 12-acre artificial reef, show an abundance of sea life and habitat colonization. Post-construction reports of the seagrass mitigation site show new seagrass recruitment growth and a 97% survival of planted plots.

deep dredge
USACE photo

Recent post-construction monitoring reports also provide a complete assessment and characterization of the sea floor communities during and after project work.

The reports compare monitoring data to preconstruction surveys and information, and provide observations of project-related and natural sediment settling throughout construction.

Scientists mapped the extent of project-related sediment during construction, which measures 252.4 acres across the hardbottom, middle and outer reef areas.

Results show that sediment levels have either dissipated or are dissipating in most areas.

Upcoming monitoring efforts will focus on documenting recovery of areas previously monitored, as well as observing and determining the distribution of any permanent effects across and along the reef system near the channel.

The Deep Dredge

Miami Harbor construction brought the entrance channel depth to 52 feet, and widened the outermost portion of the entrance channel to 800 feet.

The project also widened portions of the inner channel and deepened it to 50 feet.

In total, five different dredges removed more than five million cubic yards of rock, limestone and sand.

The Miami Harbor project is the first Federal navigation project in the southeast built to a 50 feet depth to accommodate today’s shipping needs.

[mappress mapid=”21618″]