2. The Hudson River Is Also a ‘Drowned River’

The term “drowned river” may sound like an oxymoron, but it’s actually used to describe the geological state of the Hudson River estuary. After the retreat of the Wisconsin glaciation, rising sea levels have drowned the coastal plain, bringing salt water above the mouth of the river. In fact, the drowned river valley rises only about 1.5 miles along 150 miles between New York City and Troy. It’s dredged to maintain a minimum depth of 9–11 meters.