Editing Delaware River (section)

==Length and free-flowing nature==

The length of the main stem of the Delaware River from the confluence of its branches to the head of [[Delaware Bay]] at Liston Point is {{convert|282|mi}}.<ref name="river-mileage">{{cite web|title=DRB river-mileage spreadsheet |url=https://www.state.nj.us/drbc/library/documents/DRB_river-mileage-spreadsheet.pdf |website=River Mileage System |publisher=Delaware River Basin Commission |access-date=24 October 2022}}</ref> However, the river's tidal estuary widens gradually, and there is no clear hydrological dividing point between the river and the bay. Liston Point is considered the head of Delaware Bay only by legal agreement between New Jersey and Delaware, as marked by a pair of survey monuments. As such, some observers may include the entire {{convert|48|mi|adj=on}} length of Delaware Bay from Liston Point to the Atlantic Ocean in the length of the river, giving the Delaware River an overall length of {{convert|330|mi}}.

Whether given as {{convert|282|mi}} or {{convert|330|mi}} long, the main stem of the Delaware River is the longest free-flowing river in the [[Eastern United States]]. "Free-flowing" means the river is not impounded by dams and its course is not significantly altered or diverted. Idaho's [[Salmon River (Idaho)|Salmon River]] is the longest free-flowing river in the [[contiguous United States]], at {{convert|425|mi}}.<ref>{{cite book |last1=Palmer |first1=Tim |title=America by rivers |date=1996 |location=Washington, D.C. |isbn=1559632631}}</ref>

There are two [[wing dam]]s on the river, one between [[Lambertville, New Jersey|Lambertville]] and [[New Hope, Pennsylvania|New Hope]] and one between [[Lumberville, Pennsylvania|Lumberville]] and [[Raven Rock, New Jersey|Raven Rock]]. The wing dams affect the accumulation of sediment but do not cross the entire width of the river. Many tributaries of the Delaware River are dammed or diverted, including its two upper branches. [[Cannonsville Reservoir]] impounds the [[West Branch Delaware River|West Branch]] and [[Pepacton Reservoir]] impounds the [[East Branch Delaware River|East Branch]], controlling the release of water in to the main stem Delaware River.