The Hackensack River courses southward for approximately through Rockland County in New York and Bergen and Hudson counties in northeastern New Jersey, forming the border of the latter two for part of its length. Its source, as identified by the U.S. Geological Survey (Hydrological code 02030103901), is in New City, New York. The river empties into Newark Bay between Kearny Point (South Kearny) and Droyer's Point (Jersey City). The area was settled by Bergen Dutch who established regular water crossings at Douwe's Ferry and Little Ferry. The first bridge crossing of the Hackensack was at Demarest Landing (now Old Bridge Road), built in 1724, which was replaced by that at New Bridge Landing in 1745. The first railroad crossing was completed by the NJRR in 1834, and was soon followed by many others. By the early 1900s conflicts between rail and maritime traffic led to calls for changes in regulations giving priority to trains. At one time, Van Buskirk Island, created in 1804, was the head of navigation, but freshwater flow in the Hackensack has been diminished by construction of dams, namely the Oradell (1923), the DeForest (1952), and the Tappan (1972). The river is now tidally influenced to the island. The Hackensack has only been channelized to Milepoint 3.5 at the Riverbend in Hudson County. The accumulation of silt has diminished the depth, and thus navigability, of the Lower Hackensack. which at one time was a major waterway for towboats and river barges in the Port of New York and New Jersey. Since 1999, the bridge at Milepoint 16.3 is the most upstream bridge required by the Code of Federal Regulations to open on request, though no requests have made since 1994. The Lower Hackensack remains partially in use for commercial maritime traffic, notably for coal deliveries to the Hudson Generating Station. and sewage sludge for treatment at a facility on the bay. Downstream of the power plant, vehicular moveable bridges (at MP 1.8 and MP 3.1) are required at all times to open on demand. and rail crossings to open on 1-hour notice. As of 2012 there were plans to replace the Wittpenn Bridge, a vehicular bridge at MP 3.1, with a new vertical lift bridge and the Portal Bridge, a rail swing bridge at MP 5.0, with a through arch bridge. Crossings Abbreviations CNJ=Central Railroad of New Jersey CR=County Road, County Route CSXT=CSX Transportation DL&W=Delaware, Lackawanna and