Man\u27s Physical Effects on the Elizabeth RIver

Man\u27s ever increasing activities in the Elizabeth River, i.e. dredging, disposal of dredged material and waterfront development, have drastically altered the river floor, reshaped the shoreline and changed the circulation. Long-continued dredging of shipping channels, which is fostered by coal export, larger ships, and military needs, has moved 220 million cu yds of sediment since 1870. As a result channel depth has increased 1.8 fold, and maintenance dredging rates have doubled about every 35 years. Open water disposal released 40 million cu yds into Hampton Roads and lower Chesapeake Bay. Landfill buried tributary creeks, moved the waterfront into the river and reduced the river area by 27%. As a consequence of reduced area and greater channel depth, current velocity has diminished and near-bottom salinity likely increased. These conditions induce faster sedimentation that in turn, creates a need for greater maintenance dredging and hence, greater disposal. The dredge and fill cycle, therefore, is self-perpetuating. The long-term trends of channel deepening, enlargement, and landfill, are expected to continue in response to larger ships, military needs and projected sea-level rise.https://scholarworks.wm.edu/vimsbooks/1155/thumbnail.jp