The city of Portland has announced it has received state and federal approvals to build Maine’s first Confined Aquatic Disposal (CAD) cell in Portland Harbor to address long-term dredging needs according to a press release issued by the city’s spokeswoman
The city of Portland and its partners, the city of South Portland, the State of Maine the Portland Harbor Commission, have been working for years to find a solution for dredging the piers, wharfs and waterfront properties in Portland Harbor.
“We’re losing the best berths in the Harbor,” said Bill Needelman, Portland Waterfront Coordinator. “Commercial vessels want to be in protected water and that’s where sedimentation is the most rapid.”
According to Needelman, in Portland Central Waterfront alone, over 3,000 linear feet of commercial berthing is now entirely unusable due to sediment build up. Additionally, vessel support space that was previously built for large vessels for now only functional for smaller boats due to decreased water depths.
Similar conditions exist on the South Portland side of the Harbor where sedimentation has caused a significant reduction in commercial pier and dock berthing space as well as marina berthing space. City Manager, Scott Morelli, noted that with more than 1,000 boat slips at five marinas, South Portland’s waterfront businesses are an important contributor to the local and regional economy bringing many seasonal slip tenants as well as many short-term marine visitors to the city. He noted that the approval of the CAD Cell is the next step to getting the harbor dredge project completed.
The solution for sediment buildup is dredging. However, any sediment dredged needs to be disposed of and urban sediments are typically contaminated with pollution from roads, rooftops and “legacy” pollution from long departed industries. To address the polluted sediment problem, the project team identified CAD Cell technology as the path toward a more useful and cleaner harbor. CAD Cells form an important part of the equation in the rehabilitation and maintenance of many historic ports with successful projects like New Bedford and Boston harbors in Massachusetts.
The total CAD Cell and Harbor Dredge Project is expected to cost in the neighborhood of $30 million. A recent economic assessment of Portland Harbor estimated the direct and indirect economic output from the waterfront economy is approximately $1 billion annually.