Geophysics and Dredging in the Giant New York Harbor Deepening Project

The US Army Corps of Engineers and the Port Authority of New York and New Jersey are deepening 26 miles of navigation channels of New York harbor from –40 to –50ft MLW. Quantifying and separating contaminated sediments and undiggable rock from clean sediments and diggable rock are important dredging management questions. To remove and dispose contaminated sediments costs 7 times the cost of removing and disposing clean sands and silts. To blast and remove undiggable rock costs 10 times the cost of removing clean diggable materials. We map the geology and the physical properties of the rocks and sediments throughout dredging projects. All data, maps, and cross-sections are compiled into a single reference frame. All measurements are integrated in the interpretation. The maps and cross-sections constitute the primary information for managing the construction and engineering of the harbor deepening project.