Winter 1999: Dredging

Up to a million cubic yards of sediment each year must be dredged if access to Long Island Sound’s commercial and recreational ports and harbors is to be maintained. Where does the sediment come from? Some of it is from rivers and streams that carry naturally suspended sediment into Long Island Sound. Stormwater pipes carry sediment that runs off of roads and parking lots. Currents and storms move and deposit sediment along the Sound’s shoreline. These processes would eventually lead to the filling of many waterways with sand and mud.

But there is something else that can happen to the sediment as it is transported to the Sound or as it sits on the Sound’s bottom. Contaminants, such as heavy metals, PCBs, and other organic compounds, adhere to the sediment. Some of these contaminants are the result of current activities (has your car ever dripped oil?) and some are a legacy of past industrial discharges. In either case, this contamination raises environmental concerns with how to safely dispose of the dredged material.

To view the full 1999 Winter newsletter, download the pdf document