Miami River Maintenance Dredging, Miami, Florida

U.S. Army Corps of Engineers, Jacksonville District

The Miami River was first dredged in the early 1900s. As the city developed, the river became the major outlet for stormwater and untreated sewage. In 1933, the U.S. Army Corps of Engineers (USACE) deepened the river to 15 feet and Miami became Florida’s fourth largest port. To restore navigational depth, USACE recommended the current project: dredging the 5.5 miles of the river from Biscayne Bay to the airport expressway.

The Weston Solutions, Inc., and Bean Environmental LLC Joint Venture (WESTON/Bean) was awarded the Miami River project after developing a fully integrated dredging and sediment processing approach to remove approximately 800,000 cubic yards of sediment and restore operational depths for the shipping channel. Approximately  615,000 cubic yards are expected to be dredged from the federally maintained main channel, and 185,000 from the adjacent non-federal side channels.

The supplemental non-federal dredging project will be performed in concert with the primary removal operations in the navigation channel. As an added value, private and public berthing areas and access channels will be incorporated into the project to efficiently remove 70 years of accumulated sediment.

Dredging

After considering marine traffic, debris, and environmental concerns such as minimizing turbidity, WESTON/Bean determined that a mechanical excavator dredge is the most practical and cost-effective method of dredging. A mechanical dredge facilitates dredging contaminated sediments in the congested waterway while handling substantial quantities of debris. To minimize production and commercial traffic delays, WESTON/Bean developed a marine traffic control plan that meets USACE approval, and an experienced Miami River tugboat pilot coordinated river traffic with our dredging operation.

Materials Handling

WESTON/Bean will evaluate each barge of dredged material to determine the most effective sediment processing method:

• Sand separation/mechanical dewatering
• Direct loading into trucks from barges at the dockside processing site
• Gravity draining in a staging area

Debris will be removed at the dockside processing site unloading facility and materials will be screened down to the appropriate size for processing. All barge unloading, debris removal, sand separation, and mechanical dewatering will be performed at the dockside staging area.

Pre-Testing 

Considering the variation in sediment characteristics encountered in the river, core samples will be collected during barge loading to decide the most efficient processing method for a given bargeload. The samples will be taken to the on-site laboratory and analyzed for total solids, sand, and fines content.

Water Management

All water discharged to the river will be in accordance with the approved project-specific Environmental Resource Permit (ERP). Water will be treated before being discharged back into the river.

Environmental Protection and Permits

WESTON/Bean will institute environmental quality control procedures to ensure compliance with local, state, and federal regulations and permits. Both the dredging and land-side operations will be monitored to limit and minimize noise, odors, and air pollution, including dust. Stormwater runoff and effluent from dredging and landside processing will be carefully controlled to comply with project-specific requirements.

Community Relations

To ensure project success, WESTON/Bean will maintain and communicate a proactive community relations and impact plan for the surrounding communities and businesses. The plan will address the following:

• Public information meetings
• Scope of work
• Dredging, processing, and disposal of materials
• Marine and land traffic flow
• Coordination of bridge closings
• Mitigation for odor, noise, and dust control

In conjunction with USACE, WESTON/Bean will communicate with the Miami River Commission and the Miami and Miami-Dade County commissioners to coordinate public information meetings and inform them of project status and schedule. WESTON/Bean will also create and maintain an interactive Miami River Project Web site linked to the Miami River Commission’s Web site.

Community Benefits

The Miami River Maintenance Dredging Project is part of a larger plan to improve the overall environment and commercial effectiveness of the river and its surroundings. Key goals of the overall project include the following:

• Restored channel depth for navigation
• Improved water quality
• Coordinated public access and maritime use
• Enhanced ecological system within the Miami metropolitan area
• Reinvigorated river community including bridges, greenways, shipping, public transportation, planning, zoning, housing, and crime control