View source for Delaware River

{{Short description|Major river on the East Coast of the United States}}
{{About|the river in the Eastern United States}}
{{Use American English|date = August 2019}}
{{Use mdy dates|date=September 2015}}
{{Infobox river
| name               = Delaware River
| image              = 2021-06-16 09 10 03 View of the Delaware Water Gap from the Delaware River Viaduct over the Delaware River on the border of Knowlton Township, Warren County, New Jersey and Upper Mount Bethel Township, Northampton County, Pennsylvania.jpg
| image_size         = 260px
| image_caption      = The Delaware River flowing through the [[Delaware Water Gap]] between [[Pennsylvania]] (left) and [[New Jersey]] (right)
| map                = Delaware river basin map.png
| map_size           = 260px
| map_caption        = Map of the Delaware River watershed, showing major tributaries and cities
| mapframe           = yes
| mapframe-zoom      = 6
| subdivision_type1  = Country
| subdivision_name1  = [[United States]]
| subdivision_type2  = State
| subdivision_name2  = [[New York (state)|New York]], [[New Jersey]], [[Pennsylvania]], [[Delaware]], and [[Maryland]], U.S.
| subdivision_type3  = County
| subdivision_name3  =
| subdivision_type4  = Town
| subdivision_name4  =
| subdivision_type5  = Cities
| subdivision_name5  = [[Margaretville, New York|Margaretville, NY]], [[Delhi, New York|Delhi, NY]], [[Deposit (town), New York|Deposit, NY]], [[Hancock, New York|Hancock, NY]], [[Callicoon, New York|Callicoon, NY]], [[Lackawaxen, Pennsylvania|Lackawaxen, PA]], [[Port Jervis, New York|Port Jervis, NY]], [[Stroudsburg, Pennsylvania|Stroudsburg, PA]], [[Easton, Pennsylvania|Easton, PA]], [[New Hope, Pennsylvania|New Hope, PA]], [[Trenton, New Jersey|Trenton, NJ]], [[Camden, New Jersey|Camden, NJ]], [[Philadelphia|Philadelphia, PA]], [[Chester, Pennsylvania|Chester, PA]], [[Wilmington, Delaware|Wilmington, DE]], [[Salem, New Jersey|Salem, NJ]], [[Dover, Delaware|Dover, DE]]
| length             = {{convert|282|mi}} to Delaware Bay; {{convert|330|mi}} to the Atlantic Ocean<ref name="river-mileage"/> 
| width_min          =
| width_avg          =
| width_max          =
| depth_min          =
| depth_avg          =
| depth_max          =
| discharge1_location= [[Trenton, New Jersey|Trenton]]
| discharge1_min     = {{convert|4310|cuft/s|m3/s|abbr=on}}
| discharge1_avg     = {{convert|12100|cuft/s|m3/s|abbr=on}}
| discharge1_max     = {{convert|329000|cuft/s|m3/s|abbr=on}}
| discharge2_location= [[Port Jervis]]
| discharge2_min     = {{convert|1420|cuft/s|m3/s|abbr=on}}
| discharge2_avg     = {{convert|7900|cuft/s|m3/s|abbr=on}}{{convert|282|mi}}
| discharge2_max     = {{convert|52900|cuft/s|m3/s|abbr=on}}
<!---------------------- BASIN FEATURES -->
| source1            = [[West Branch Delaware River|West Branch]]
| source1_location   = [[Mount Jefferson (New York)|Mount Jefferson]], [[Jefferson, New York|Town of Jefferson]], [[Schoharie County, New York|Schoharie County]], [[New York (state)|New York]], [[United States]]
| source1_coordinates= {{coord|42|27|12|N|74|36|26|W|region:US-NY_type:river|display=inline}}
| source1_elevation  = {{convert|2240|ft|abbr=on}}
| source2            = [[East Branch Delaware River|East Branch]]
| source2_location   = Grand Gorge, [[Roxbury, New York|Town of Roxbury]], [[Delaware County, New York|Delaware County]], [[New York (state)|New York]], [[United States]]
| source2_coordinates= {{coord|42|21|26|N|74|30|42|W|region:US-NY_type:river|display=inline}}
| source2_elevation  = {{convert|1560|ft|abbr=on}}
| source_confluence            =
| source_confluence_location   = [[Hancock, New York|Town of Hancock]], [[Delaware County, New York|Delaware County]], [[New York (state)|New York]], [[United States]]
| source_confluence_coordinates= {{coord|41|56|20|N|75|16|46|W|region:US-NY_type:river|display=inline}}
| source_confluence_elevation  = {{convert|880|ft|abbr=on}}
| mouth              = [[Delaware Bay]]
| mouth_location     = [[Delaware]], [[United States]]
| mouth_coordinates  = {{coord|39|25|13|N|75|31|11|W|region:US_type:river|display=inline,title}}
| mouth_elevation    = {{convert|0|ft|abbr=on}}
| progression        =
| river_system       =
| basin_size         = {{convert|13539|sqmi|abbr=on}}
| tributaries_left   = [[Neversink River]], [[Pequest River]], [[Musconetcong River]]
| tributaries_right  = [[Lehigh River]], [[Schuylkill River]], [[Christina River]]
| custom_label       =
| custom_data        = {{Designation list
 | embed                   = yes
 | designation1            = nwsr
 | designation1_type       = Scenic, Recreational}}
| extra              = 
}}
{{Delaware River map}}
The '''Delaware River''' is a major [[river]] in the [[Mid-Atlantic (United States)|Mid-Atlantic]] region of the United States and is the longest free-flowing (undammed) river in the [[Eastern United States]]. From the meeting of its branches in [[Hancock (village), New York|Hancock, New York]], the river flows for {{convert|282|mi}} along the borders of [[New York (state)|New York]], [[Pennsylvania]], [[New Jersey]], and [[Delaware]], before emptying into [[Delaware Bay]].

The river has been recognized by the [[National Wildlife Federation]] as one of the country's Great Waters<ref>{{cite news|author=National Wildlife Federation|title=America's Great Waters Coalition|date=August 18, 2010|url=http://www.nwf.org/Wildlife/What-We-Do/Waters/Great-Waters-Restoration/Great-Waters-Coalition.aspx|access-date=August 18, 2011|archive-url=https://web.archive.org/web/20110815213851/http://www.nwf.org/Wildlife/What-We-Do/Waters/Great-Waters-Restoration/Great-Waters-Coalition.aspx|archive-date=August 15, 2011|url-status=live}}</ref> and has been called the "Lifeblood of the Northeast" by [[American Rivers]].<ref>{{cite web |title=Delaware River |url=https://www.americanrivers.org/river/delaware-river/ |website=www.americanrivers.org |publisher=American Rivers |access-date=23 March 2023}}</ref> Its [[drainage basin|watershed]] drains an area of {{convert|13539|sqmi}} and provides drinking water for 17&nbsp;million people, including half of [[New York City]] via the [[Delaware Aqueduct]].

The Delaware River has two branches that rise in the [[Catskill Mountains]] of New York: the [[West Branch Delaware River|West Branch]] at [[Mount Jefferson (New York)|Mount Jefferson]] in [[Jefferson, New York|Jefferson]], [[Schoharie County, New York|Schoharie County]], and the [[East Branch Delaware River|East Branch]] at [[Grand Gorge, New York|Grand Gorge]], [[Delaware County, New York|Delaware County]]. The branches merge to form the main Delaware River at [[Hancock (village), New York|Hancock, New York]]. Flowing south, the river remains relatively undeveloped, with {{convert|152|mi}} protected as the [[Upper Delaware Scenic and Recreational River|Upper]], [[Middle Delaware National Scenic River|Middle]], and [[Lower Delaware National Wild and Scenic River|Lower]] Delaware [[National Wild and Scenic Rivers System|National Scenic Rivers]].<ref>{{cite web|title=National Wild and Scenic Rivers in the DRB |url=https://nj.gov/drbc/basin/wild.html |website=nj.gov |publisher=Delaware River Basin Commission |access-date=24 October 2022}}</ref> At [[Trenton, New Jersey]], the Delaware becomes [[tidal river|tidal]], [[navigability|navigable]], and more [[maritime industry|industrial]]. This section forms the backbone of the [[Delaware Valley]] metropolitan area, serving the port cities of [[Philadelphia]], [[Camden, New Jersey]], and [[Wilmington, Delaware]]. The river flows into [[Delaware Bay]] at Liston Point, {{convert|48|mi}} upstream of the bay's outlet to the Atlantic Ocean, between [[Cape May]] and [[Cape Henlopen]].<ref name="river-mileage" />

Before the arrival of European settlers, the river was the homeland of the [[Lenape]] native people. They called the river Lënapei Sipu or Lenapewihittuk, meaning Lenape River, and Kithanne, meaning the largest river in this part of the country.<ref name="Names which the Lenni Lenape or Del">{{citation |last1=Heckewelder |first1=John |last2=Du Ponceau |first2=Peter S. |date=1834 |title=Names which the Lenni Lenape or Delaware Indians, who once inhabited this country, had given to Rivers, Streams, Places, &c. |jstor=1004837 |journal=Transactions of the American Philosophical Society |volume=4 |pages=351–396|doi=10.2307/1004837 }}</ref>

In 1609, the river was visited by a [[Dutch East India Company]] expedition led by [[Henry Hudson]], an English navigator hired to find a western route to [[Cathay]] (China). His encounters set the stage for [[New Netherland|Dutch colonization of North America]] in the 17th century. Early Dutch and Swedish settlements were established along the lower section of the river and [[Delaware Bay]]. Both [[colonialism|colonial powers]] called the river the ''South River'' (Zuidrivier), distinguishing it from the ''North River—''today’s [[Hudson River]]. After the English expelled the Dutch and took control of the New Netherland colony in 1664, the river was renamed ''Delaware'' after [[Thomas West, 3rd Baron De La Warr|Sir Thomas West]], 3rd Baron De La Warr, an English nobleman and the Virginia colony's first royal governor, who defended the colony during the [[First Anglo-Powhatan War]]. [[George Washington's crossing of the Delaware River]] in 1776 led victory in the [[Battle of Trenton]], a pivotal moment in the [[American Revolution]].

==Name==
[[File:3rdLordDeLaWarr.jpg|thumb|The Delaware River is named in honor of [[Thomas West, 3rd Baron De La Warr|Thomas West]], 3rd Baron De La Warr]]

The Delaware River is named in honor of [[Thomas West, 3rd Baron De La Warr]] (1577–1618), an English nobleman and the [[Colony of Virginia|Virginia colony's]] [[List of colonial governors of Virginia|first royal governor]], who defended the colony during the [[First Anglo-Powhatan War]].<ref name="DNB">{{cite DNB|no-icon=1|first=Albert Frederick|last=Pollard|wstitle=West, Thomas (1577-1618) <!--N.B.: Hyphen not en dash on Wikisource. --> |display=West, Thomas (1577–1618)|volume=60|pages=344–345}}</ref> Lord de la Warr waged a [[Punitive expedition|punitive campaign]] to subdue the [[Powhatan]] after they had killed the colony's council president, [[John Ratcliffe (governor)|John Ratcliffe]], and attacked the colony's fledgling settlements.<ref>{{cite book |editor-last=Tyler |editor-first=Lyon Gardiner |title=Encyclopedia of Virginia Biography |location=New York |publisher=Lewis Historical Publishing Company |year=1915 |volume=I |pages=33–34 }}</ref><ref>{{cite book |last=Grenier |first=John |title=The First Way of War: The American War-Making of the Frontier, 1607–1814 |url=https://archive.org/details/firstwaywarameri00gren |url-access=limited |location=New York |publisher=Cambridge University Press |year=2005 |pages=[https://archive.org/details/firstwaywarameri00gren/page/n39 24]–25 |isbn=0-521-84566-1 }}</ref> Lord de la Warr arrived with 150 soldiers in time to prevent the colony's original settlers at [[Historic Jamestowne|Jamestown]] from giving up and returning to England and is credited with saving the Virginia colony.<ref name="DNB" /> The name of the barony (later an [[Earl De La Warr|earldom]]) is pronounced as in the current spelling form "Delaware" ({{IPAc-en|audio=en-us-Delaware.ogg|ˈ|d|ɛ|l|ə|w|ɛər}} {{respell|DEL|ə|wair}})<ref>''Random House Dictionary''</ref> and is thought to derive from [[French language|French]] ''de la Guerre''.

It has often been reported that the river and bay received the name "Delaware" after [[English colonial empire|English]] forces under [[Richard Nicolls]] expelled the [[Dutch colonization of the Americas|Dutch]] and took control of the [[New Netherland|New Netherland colony]] in 1664.<ref>World Digital Library. [http://www.wdl.org/en/item/4062 ''Articles about the Transfer of New Netherland on the 27th of August, Old Style, Anno 1664''] {{Webarchive|url=https://web.archive.org/web/20130126104904/http://www.wdl.org/en/item/4062/ |date=January 26, 2013 }}. Retrieved March 21, 2013</ref><ref>Versteer, Dingman (editor). "New Amsterdam Becomes New York" in ''[https://archive.org/details/newnetherlandreg00vers The New Netherland Register]''. Volume 1 No. 4 and 5 (April/May 1911): 49-64.</ref> However, the river and bay were known by the name ''Delaware'' as early as 1641.<ref>Evelin, Robert. ''A direction for Adventurers With small stock to get two for one, and good land freely : And for Gentleman, and all Servants, Labourers, and Artificers to live plentifully, And the true Description of the healthiest, pleasantest and richest plantation of New Albion in North Virginia''. (London, s.n., 1641).</ref> The [[U.S. state|state]] of Delaware was originally part of the [[William Penn]]'s [[Province of Pennsylvania|Pennsylvania colony]]. In 1682, the [[James II of England|Duke of York]] granted Penn's request for access to the sea and leased him the territory along the western shore of Delaware Bay, which became known as the "Lower Counties on the Delaware".<ref>{{cite book |last=Munroe |first=John A. |chapter-url=https://books.google.com/books?id=vs7NcOKnlNUC&pg=PA45 |chapter=Chapter 3. The Lower Counties On The Delaware |title=History of Delaware |location=Newark, Delaware |publisher=University of Delaware Press |year=2006 |page=45 |isbn=0-87413-947-3 }}</ref> In 1704, the Lower Counties were given political autonomy to form a separate provincial assembly, but they shared Pennsylvania's provincial governor until the two colonies separated on June 15, 1776, and they remained separate as [[U.S. state|states]] after the establishment of the United States.

The name "Delaware" also came to be used as a collective name for the [[Lenape]], a [[Native Americans in the United States|Native American]] people who inhabited an area of the basins of the [[Susquehanna River]], Delaware River, and lower [[Hudson River]] in the [[northeastern United States]] at the time of European settlement,<ref>{{cite book |last=Schutt |first=Amy C. |title=Peoples of the River Valleys: The Odyssey of the Delaware Indians |location=Philadelphia |publisher=University of Pennsylvania Press |year=2007 |isbn=978-0-8122-3993-5 }}</ref> as well as for their [[Delaware languages|language]]. As a result of disruption following the [[French and Indian War]], [[American Revolution|American Revolutionary War]], and the later Indian removals from the eastern United States, the name "Delaware" has been spread with the Lenape's diaspora to municipalities, counties and other geographical features in the American Midwest and Canada.<ref>{{cite book |last=Weslager |first=Charles A. |title=The Delaware Indians: A History |location=New Brunswick, New Jersey |publisher=Rutgers University Press |year=1990 |isbn=0-8135-1494-0 }}</ref> The Lenape refer to this river as the Lënapei Sipu, Lenapewihittuck, or Kithanna.<ref name="Names which the Lenni Lenape or Del"/>

==Length==
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}}.

At either length 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.

==Watershed==
{{See also|List of Delaware River tributaries}}
[[File:Delaware headwaters map.png|thumb|The headwaters of the Delaware River, including the river's East and West Branches and other tributaries]]

The Delaware River's [[drainage basin]] has an area of {{convert|13539|sqmi|km2}} and encompasses 42 counties and 838 municipalities in five U.S. states: New York, New Jersey, Pennsylvania, Maryland, and Delaware.<ref name="PhillyWaterDelRWatershedPlan">Philadelphia Water Department. [http://www.phillyriverinfo.org/WICLibrary/Delaware%20River%20Source%20Water%20Protection%20Plan.pdf "Moving from Assessment to Protection…The Delaware River Watershed Source Water Protection Plan" (PWSID #1510001)] {{webarchive|url=https://web.archive.org/web/20130728123538/http://www.phillyriverinfo.org/WICLibrary/Delaware%20River%20Source%20Water%20Protection%20Plan.pdf|date=July 28, 2013}} (June 2007). Retrieved July 17, 2013.</ref>{{rp|9}}  This total area constitutes approximately 0.4% of the land mass in the United States.<ref name="PhillyWaterDelRWatershedPlan" />{{rp|9}} In 2001, the watershed was 18% agricultural land, 14% developed land, and 68% forested land.<ref name="PhillyWaterDelRWatershedPlan" />{{rp|vi}}

There are 216 tributary streams and creeks comprising an estimated 14,057 miles of streams and creeks, in the watershed.<ref name="PhillyWaterDelRWatershedPlan" />{{rp|p.11,25}}  While the watershed is home to 4.17&nbsp;million people according to the 2000 Federal Census, these bodies of water provide drinking water to 17&nbsp;million people—roughly 6% of the population of the United States.<ref name="PhillyWaterDelRWatershedPlan" />{{rp|vi, 9}}  The waters of the Delaware River's basin are used to sustain "fishing, transportation, power, cooling, recreation, and other industrial and residential purposes."<ref name="PhillyWaterDelRWatershedPlan" />{{rp|9}} It is the 33rd largest river in the United States in terms of flow, but is among the nation's most heavily used rivers in daily freight tonnage.<ref name="PhillyWaterDelRWatershedPlan" />{{rp|p.11}} The average annual flow rate of the Delaware is 11,700 cubic feet per second at [[Trenton, New Jersey]].<ref name="PhillyWaterDelRWatershedPlan" />{{rp|9}} With no dams or impediments on the river's main stem, the Delaware is one of the few remaining large free-flowing rivers in the United States.<ref name="PhillyWaterDelRWatershedPlan" />{{rp|11}}

{{Wide image|Delaware river chart 1655.jpeg|800px|A 1655 Swedish nautical chart showing part of the Delaware River when the river was part of the Swedish colony [[New Sweden]]}}
<gallery widths="200px" heights="200px">
File:East Branch Delaware River at Margaretville, NY.jpg|East Branch of the Delaware River near [[Margaretville, New York]]
File:Hawk's Nest view of DelawareR.jpg|Canoeing on the river at [[Hawk's Nest (Orange County, New York)]]
File:Delaware and Hudson Canal near Summitville, NY.jpg|A still remaining section of the [[Delaware and Hudson Canal]] seen from [[U.S. Route 209|U.S. 209]] near [[Summitville, New York]]
File:Easton–Phillipsburg Toll Bridge, Dec 2021.jpg|[[Easton–Phillipsburg Toll Bridge]] crosses the Delaware, connecting [[Easton, Pennsylvania]] and [[Phillipsburg, New Jersey]], in the [[Lehigh Valley]].
File:BenjaminFranklinBridgeAtNight.jpg|[[Benjamin Franklin Bridge]] crosses the Delaware, connecting [[Philadelphia]] and [[Camden, New Jersey]].
File:Walt Whitman Bridge at night.jpg|[[Walt Whitman Bridge]] crosses the Delaware, connecting [[Philadelphia]] and [[Gloucester City, New Jersey]].
File:DingmansFerryBridgeSide.jpg|[[Dingman's Ferry Bridge]] connects [[Sandyston Township, New Jersey]], and [[Delaware Township, Pike County, Pennsylvania|Delaware Township]] in [[Pike County, Pennsylvania]]
File:Delaware River DWG USA.jpg|The Delaware within the southern portion of the [[Delaware Water Gap National Recreation Area]], near [[Worthington State Forest]] in [[New Jersey]]
File:2006 flood Westfall PA.png|A flood in [[Westfall Township, Pennsylvania|Westfall, Pennsylvania]], in 2006
</gallery>

==Course==
{{Redirect|Delaware River Valley|the metropolitan area along the Central and Lower Delaware River known as the Delaware Valley|Philadelphia metropolitan area}}

===West Branch of the Delaware===
{{main|West Branch Delaware River}}

The [[West Branch Delaware River|West Branch of the Delaware River]], also called the Mohawk Branch, spans approximately {{convert|90|mi|km}} from the northern [[Catskill Mountains]] to its [[confluence]] with the Delaware River's East Branch at [[Hancock, New York]]. The last {{convert|6|mi|km}} forms part of [[New York–Pennsylvania border|the boundary between New York and Pennsylvania]].

The West Branch rises in [[Schoharie County, New York|Schoharie County]], New York at {{convert|1886|ft}} above sea level, near [[Mount Jefferson (New York)|Mount Jefferson]], and flows tortuously through the plateau in a deep trough. The branch flows generally southwest, entering [[Delaware County, New York|Delaware County]] and flowing through the towns of [[Stamford, New York|Stamford]] and [[Delhi, New York|Delhi]]. In southwestern Delaware County it flows in an increasingly winding course through the mountains, generally southwest. At [[Stilesville, New York|Stilesville]] the West Branch was impounded in the 1960s to form the [[Cannonsville Reservoir]], the westernmost of the reservoirs in the New York City water system. It is the most recently constructed New York City reservoir and began serving the city in 1964. Draining a large watershed of {{convert|455|sqmi}}, the reservoir's capacity is {{convert|95.7|e9USgal|m3}}. This water flows over halfway through the reservoir to enter the {{convert|44|mi|km|adj=on}} West Delaware Tunnel in [[Tompkins, New York|Tompkins]], New York. Then it flows through the aqueduct into the [[Rondout Reservoir]], where the water enters the {{convert|85|mi|km}} [[Delaware Aqueduct]], that contributes to roughly 50% of the city's drinking water supply. At [[Deposit (town), New York|Deposit]], on the border between [[Broome County, New York|Broome]] and Delaware counties, it turns sharply to the southeast and is paralleled by [[New York State Route&nbsp;17]]. It joins the East Branch at {{convert|880|ft}} above sea level at [[Hancock (town), New York|Hancock]] to form the Delaware.

===East Branch of the Delaware===
{{main|East Branch Delaware River}}

Similarly, the [[East Branch Delaware River|East Branch]] begins from a small pond south of [[Grand Gorge, New York|Grand Gorge]] in the [[List of towns in New York (state)|town]] of [[Roxbury, New York|Roxbury]] in [[Delaware County, New York|Delaware County]], flowing southwest toward its impoundment by New York City to create the [[Pepacton Reservoir]], the largest reservoir in the [[New York City water supply system]]. Its tributaries are the Beaver Kill River and the Willowemoc Creek which enter into the river {{convert|10|mi|km|spell=in}} before the West Branch meets the East Branch. The confluence of the two branches is just south of [[Hancock (village), New York|Hancock]].

The East Branch and West Branch of the Delaware River parallel each other, both flowing in a southwesterly direction.

===Upper Delaware Valley===
{{see also|Upper Delaware Scenic and Recreational River}}

From [[Hancock, New York]], the Delaware flows between the northern [[Pocono Mountains|Poconos]] in Pennsylvania, and the lowered shale beds north of the Catskills. The river flows down a broad [[Appalachian Mountains|Appalachian]] valley, passing [[Hawk's Nest (Orange County, New York)|Hawk's Nest overlook]] on the Upper Delaware Scenic Byway. The river flows southeast for 78 miles through rural regions along the New York-Pennsylvania border to Port Jervis and  [[Shawangunk Ridge]].<!--{{rp|p.9}}
* Mongaup River
* Neversink River-->

===The Minisink===
{{Main|Minisink}}

At [[Port Jervis, New York|Port Jervis]], New York, it enters the Port Jervis trough. At this point, the Walpack Ridge deflects the Delaware into the Minisink Valley, where it follows the southwest [[Strike and dip|strike]] of the eroded [[Marcellus Formation]] [[bed (geology)|beds]] along the Pennsylvania–New Jersey state line for {{convert|25|mi|km}} to the end of the ridge at Walpack Bend in the [[Delaware Water Gap National Recreation Area]].<ref name="White">{{cite web|url=http://www.njgeology.org/enviroed/newsletter/v2n1.pdf |title=Karst in the Delaware Water Gap National Recreation Area |author1=White, Ron W. |author2=Monteverde, Donald H. |work=Unearthing New Jersey Vol. 2, No. 1 |date=Feb 2006 |access-date=June 7, 2008 |publisher=New Jersey Geological Survey |archive-url=https://web.archive.org/web/20080910033019/http://www.njgeology.org/enviroed/newsletter/v2n1.pdf |archive-date=September 10, 2008 |url-status=live}}</ref><ref name="White1882">{{cite book| author = White, I.C. |author2=Chance, H.M. | year = 1882 | title = The geology of Pike and Monroe counties | series = Second Geol. Surv. of Penna. | location = Harrisburg | volume = Rept. of Progress, G6 | pages = 17, 73–80, 114–115}}</ref>
The Minisink is a [[buried valley]] where the Delaware flows in a bed of [[glacier|glacial]] [[till]] that buried the eroded bedrock during the [[last glacial period]]. It then skirts the [[Kittatinny Mountains|Kittatinny ridge]], which it crosses at the [[Delaware Water Gap]], between nearly vertical walls of [[sandstone]], [[quartzite]], and [[conglomerate (geology)|conglomerate]], and then passes through a quiet and charming country of farm and forest, diversified with plateaus and escarpments, until it crosses the Appalachian plain and enters the hills again at [[Easton, Pennsylvania|Easton]], Pennsylvania. From this point it is flanked at intervals by fine hills, and in places by cliffs, of which the finest are the Nockamixon Cliffs, {{convert|3|mi|0}} long and above {{convert|200|ft}} high.

The [[Appalachian Trail]], which traverses the ridge of Kittatinny Mountain in New Jersey, and Blue Mountain in Pennsylvania, crosses the Delaware River at the Delaware Water Gap near Columbia, New Jersey.

===Central Delaware Valley===
{{Multiple image
| width=200
| image1 = Aerial view of Trenton bridges, December 2022.jpg
| image2 = 2023-09-04 13 06 32 View of the Falls of the Delaware at low tide, looking west from Trenton, Mercer County, New Jersey towards Morrisville, Bucks County, Pennsylvania.jpg
| footer = The Falls of the Delaware at [[Trenton, New Jersey|Trenton]], where the river becomes tidal. Left - aerial view looking northwest; right - ground view from the New Jersey banks
}}
In [[Easton, Pennsylvania]], the [[Lehigh River]] joins the Delaware. At [[Trenton, New Jersey|Trenton]], the Delaware crosses the [[Atlantic Seaboard Fall Line]] with a drop of {{convert|8|ft}}.

===Lower Delaware and Tidewater===
{{See also|Delaware Valley}}

Below [[Trenton, New Jersey|Trenton]], the Delaware flows between [[Philadelphia]] and [[New Jersey]] as it transitions into a broad, sluggish inlet of the sea, with many marshes along its side, widening steadily into its great estuary, [[Delaware Bay]].

The Delaware River constitutes the boundary between Delaware and New Jersey. The Delaware–New Jersey border is actually at the easternmost river shoreline within the [[Twelve-Mile Circle|Twelve-Mile Circle of New Castle]], rather than at mid-river, mid-channel or [[thalweg]], so small portions of land lying west of the shoreline, but on the New Jersey side of the river, are [[pene-exclave]]s under the jurisdiction of Delaware. The rest of the borders follow a mid-channel approach.

==History==
[[File:Treaty of Penn with Indians by Benjamin West.jpg|thumb|[[Benjamin West]]'s painting, ''The Treaty of Penn with the Indians'' (1771–1772), depicts the 1683 [[Treaty of Shackamaxon]] between [[William Penn]] and [[Tamanend]], the chief of the [[Lenape]]'s Turtle Clan. [[Voltaire]] referred to it as "the only treaty never sworn to and never broken."]]

At the time of the arrival of the [[Europe]]ans in the early 17th century, the area near the Delaware River was inhabited by the Native American [[Lenape]] people, who called the Delaware River ''Lënapei Sipu'',<ref>{{cite web |title=Lënapei Sipu |url=https://www.talk-lenape.org/detail?id=13166 |website=Lenape Talking Dictionary |publisher=Lenape Language Preservation Project |access-date=22 September 2025}}</ref> meaning "Lenape river", or ''Lenape Wihittuck'', which means "the rapid stream of the Lenape".<ref name ="USGSDel">[https://pubs.usgs.gov/bul/1245/report.pdf Delaware Place Names] {{Webarchive|url=https://web.archive.org/web/20170811214125/https://pubs.usgs.gov/bul/1245/report.pdf |date=August 11, 2017 }} [[United States Geological Survey]]</ref> The Delaware River played a key factor in the economic and social development of the Mid-Atlantic region. In the seventeenth century it provided the conduit for colonial settlement by the [[Dutch Empire|Dutch]] ([[New Netherland]]) and the [[Swedish colonial empire|Swedish]] ([[New Sweden]]). Beginning in 1664, the region became an [[English colonial empire|English possession]] as settlement by Quakers established the colonies of [[Province of Pennsylvania|Pennsylvania]] (including present-day [[Delaware]]) and [[Province of West Jersey|West Jersey]]. In the eighteenth century, cities like [[Philadelphia]], [[Camden, New Jersey|Camden]] (then Cooper's Ferry), [[Trenton, New Jersey|Trenton]], [[Wilmington, Delaware|Wilmington]] and [[New Castle, Delaware|New Castle]] were established upon the Delaware and their continued commercial success into the present day has been dependent on access to the river for trade and power. The river provided the path for the settlement of northeastern Pennsylvania's [[Lehigh Valley]], and northwestern New Jersey by [[German Palatine]] immigrants—a population that became key in the agricultural development of the region.

===Swedish Colonization (1638–1655)===
In 1638, Swedish settlers, led by Peter Menuet, established New Sweden along the Delaware River. This settlement marked one of the earliest European establishments in the region, with Fort Christina (located near modern-day Wilmington, Delaware) becoming a key trading post and symbol of Swedish colonial ambition. The Swedes engaged in peaceful land negotiations with the local Lenape people and developed a thriving colony. New Sweden became a center for trade and cultural exchange between the Swedish settlers, Native Americans, and neighboring Dutch colonies. Although the Dutch would later assert dominance over the region in 1655, New Sweden laid the groundwork for European settlement along the Delaware River. The fort and surrounding settlements played a crucial role in the early European rivalry for control of North America's resources and territory. This era of Swedish colonization is an important part of the Delaware River's history, adding to its diverse cultural legacy.

===American Revolutionary War===
{{See also|American Revolutionary War}}
[[File:Washington Crossing the Delaware by Emanuel Leutze, MMA-NYC, 1851.jpg|thumb|''[[Washington Crossing the Delaware (1851 paintings)|Washington Crossing the Delaware]]'' by [[Emanuel Leutze]], 1851, is on display at the [[Metropolitan Museum of Art]] in [[New York City]].]]
[[File:George Inness - On the Delaware River - Google Art Project.jpg|thumb|''On the Delaware River'', an oil painting ({{Circa|1861}}–1863) by [[George Inness]] now on display at [[Brooklyn Museum]]]]

The strategic Delaware River was the scene of several important campaigns during the [[American Revolutionary War]]. Perhaps the most famous event was [[George Washington's crossing of the Delaware River]] with the [[Continental Army]] on the night of December&nbsp;25–26, 1776, leading to a successful [[Battle of Trenton|surprise attack and victory]] against the [[Hessian (soldiers)|Hessian troops]] occupying [[Trenton, New Jersey]], on the morning of December 26.<ref>[[#savas2006|Savas, 2006]], p. 84</ref><ref>[[#brooks1999|Brooks, 1999]] p. 55</ref>

During the [[Philadelphia Campaign]] control of the Delaware River was urgently needed by the British, allowing their naval fleet to supply troops occupying Philadelphia. To this end, the [[Battle of Red Bank]] and the [[Siege of Fort Mifflin]] were fought on and along the shores of the Delaware by the American and British navies, commanded by [[John Hazelwood|Commodore John Hazelwood]] and [[Francis Reynolds-Moreton, 3rd Baron Ducie|Admiral Francis Reynolds]] respectively.<ref>[[#dorwart1998|Dorwart 1998]], pp. 40–41</ref><ref>[[#leach02|Leach, 1902]], p. 2</ref><ref>[[#mcgeorge1905|McGeorge, 1905]], pp. 3–7</ref> See [[:File:Philadelphia Map, 1777 Philadelphia Campaign2.jpg|historical map]] of that campaign.

===Canals===
The magnitude of the commerce of [[Philadelphia]] has made the improvements of the river below that port of great importance. Small improvements were attempted by [[Pennsylvania]] as early as 1771. Commerce was once important on the upper river, primarily prior to railway competition of 1857.

* The [[Pennsylvania Canal (Delaware Division)|Delaware Division of the Pennsylvania Canal]], running parallel with the river from Easton to Bristol, opened in 1830.
* The [[Delaware and Raritan Canal]], which runs along the New Jersey side of the Delaware River from Bulls Island, New Jersey to [[Trenton, New Jersey|Trenton]], unites the waters of the Delaware and [[Raritan River|Raritan rivers]] as it empties the waters of the Delaware River via the canal outlet in [[New Brunswick, New Jersey|New Brunswick]]. This canal water conduit is still used as a water supply source by the State of [[New Jersey]].
* The [[Morris Canal]] (now abandoned and almost completely filled in) and the [[Delaware and Hudson Canal]] connected the Delaware and [[Hudson River|Hudson rivers]].
* The [[Chesapeake and Delaware Canal]] joins the waters of the Delaware with those of the [[Chesapeake Bay]].

===Delaware Water Gap National Recreation Area===
{{See also|Tocks Island Dam Controversy}}

The [[Delaware Water Gap National Recreation Area]] came about as a result of the failure of a controversial plan to build a dam on the Delaware River at [[Tocks Island]], just north of the [[Delaware Water Gap]] to control water levels for flood control and hydroelectric power generation. The dam would have created a {{convert|37|mi|km|adj=on}} lake in the center of present park for use as a reservoir. Starting in 1960, the present-day area of the Recreation Area was acquired for the [[United States Army Corps of Engineers|Army Corps of Engineers]] through [[eminent domain]]. Between 3,000 and 5,000 dwellings were demolished, including historical sites, and about 15,000 people were displaced by the project.

Because of massive environmental opposition, dwindling funds, and an unacceptable geological assessment of the dam's safety, the government transferred the property to the [[National Park Service]] in 1978. The National Park Service found itself as the caretaker of the previously endangered territory, and with the help of the federal government and surrounding communities, developed recreational facilities and worked to preserve the remaining historical structures.<ref>''Delaware Water Gap National Recreation Area'' (pp. 7–8), Obiso, Laura, 2008.</ref><ref>[http://www.njskylands.com/pkdwgnra.htm Delaware Water Gap National Recreation Area] {{Webarchive|url=https://web.archive.org/web/20110803140204/http://www.njskylands.com/pkdwgnra.htm |date=August 3, 2011 }}, ''njskylands.com''.</ref>

The nearby [[The Shawnee Inn & Golf Resort|Shawnee Inn]],<ref name="DailyRecord1">{{cite news|title=Shawnee Marking Golden Season|url=https://www.newspapers.com/image/65387791 |access-date=December 21, 2020 |work=The Daily Record|location=Stroudsburg, Pennsylvania|date=June 17, 1960|ref=DailyRecord1}}</ref><ref name="Squeri182">Squeri, p. 182.</ref> was identified in the 1990s as the only resort along the banks of the Delaware River.<ref>{{cite book|title=Fodor's national parks and seashores of the east|date=1994|publisher=Fodor's Travel Publications|location=New York|page=164|edition=1|ref=Fodor1}}</ref><ref name="CourierNews">{{cite news|last1=Shea|first1=Barbara|title=Let the current set the pace at the Delaware Water Gap|work=The Courier-News|location=Somerville, New Jersey|date=September 11, 1994|ref=CourierNews}}</ref>

[[American Rivers]], an environmental advocacy group, named the Delaware River as the [[River of the Year]] for 2020, citing 75 years of progress in reducing pollution and restoring wildlife.<ref>{{cite news |last1=Tanenbaum |first1=Michael |title=Delaware River named 2020 River of the Year by national environmental organization |url=https://www.phillyvoice.com/delaware-river-2020-river-of-the-year-american-rivers-pennsylvania-new-york-new-jersey-maryland/ |access-date=14 August 2023 |work=PhillyVoice |date=15 April 2020 |language=english}}</ref>

==Commerce==
===Wine regions===
{{See also|New Jersey wine|Pennsylvania wine}}

In 1984, the [[U.S. Department of the Treasury]] authorized the creation of a wine region or "[[American Viticultural Area]]" called the [[Central Delaware Valley AVA]] located in southeastern [[Pennsylvania]] and [[New Jersey]]. The [[wine]] [[appellation]] includes {{convert|96000|acre|ha|0}} surrounding the Delaware River north of [[Philadelphia, Pennsylvania|Philadelphia]] and [[Trenton, New Jersey|Trenton]], New Jersey.<ref>The Wine Institute. [http://www.iwineinstitute.com/ava/avabystate.asp "American Viticultural Areas by State"] {{webarchive|url=https://web.archive.org/web/20080127115948/http://www.iwineinstitute.com/ava/avabystate.asp |date=January 27, 2008}} (2008). Retrieved February 5, 2008.</ref> In Pennsylvania, it consists of the territory along the Delaware River in [[Bucks County, Pennsylvania|Bucks County]]; in New Jersey, the AVA spans along the river in [[Hunterdon County, New Jersey|Hunterdon County]] and [[Mercer County, New Jersey|Mercer County]] from [[Titusville, New Jersey|Titusville]], New Jersey, just north of Trenton, northward to [[Musconetcong Mountain]].<ref name="CFR-CDVAVA">Code of Federal Regulations. [http://www.gpo.gov/fdsys/pkg/CFR-2012-title27-vol1/xml/CFR-2012-title27-vol1-sec9-49.xml Section 9.49 Central Delaware Valley.] {{Webarchive|url=https://web.archive.org/web/20130422114416/http://www.gpo.gov/fdsys/pkg/CFR-2012-title27-vol1/xml/CFR-2012-title27-vol1-sec9-49.xml |date=April 22, 2013 }} (27 CFR 9.49) from ''Title 27 - Alcohol, Tobacco Products and Firearms. CHAPTER I - ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY. SUBCHAPTER A - LIQUORS. PART 9 - AMERICAN VITICULTURAL AREAS. Subpart C - Approved American Viticultural Areas.'' Retrieved June 30, 2013.</ref> As of 2013, there are no [[New Jersey wine]]ries in the Central Delaware Valley AVA.<ref name="CFR-CDVAVA"/><ref>New Jersey Division of Alcoholic Beverage Control. "[[:File:New Jersey ABC.pdf|New Jersey ABC list of wineries, breweries, and distilleries]]" (February 5, 2013). Retrieved May 2, 2013. An analysis was done comparing a list of wineries provided by the New Jersey Division of Alcoholic Beverage Control with the AVA's description in the Code of Federal Regulations.</ref>

===Shipping===
In the Project of 1885, the U.S. government systematically undertook the formation of a {{convert|26|ft|adj=on}} deep federal navigation shipping channel {{convert|600|ft}} wide from [[Philadelphia]] to into [[Delaware Bay]]. The [[Rivers and Harbors Act|River and Harbor Act]] of 1899 provided for a {{convert|30|ft|adj=on}} channel {{convert|600|ft|m}} wide from Philadelphia to the deep water of the bay.<ref name="EB1911">{{EB1911|inline=1|wstitle=Delaware River|volume=7 |page=951}}</ref>

Since 1941, the Delaware River Main Channel was maintained at a depth of {{convert|40|ft|m|abbr=on}}. Since 2013 there has been a push to deepen the 102.5-mile stretch from Philadelphia and [[Camden, New Jersey|Camden]] to the mouth of the Delaware Bay to 45 feet.<ref>United States Army Corps of Engineers. ''[https://www.nap.usace.army.mil/Missions/Civil-Works/Delaware-River-Main-Channel-Deepening/ Delaware River Main Channel Deepening]'' [https://www.nap.usace.army.mil/Missions/Civil-Works/Delaware-River-Main-Channel-Deepening/]. Retrieved July 25, 2013.</ref><ref>Ruch, Robert J. Ruch (Lt. Col.), District Engineer, Philadelphia District. ''[http://www.dvrpc.org/freight/pdf/2005-02_DERiverDRVPC.pdf Delaware River Main Channel Deepening Project] {{Webarchive|url=https://web.archive.org/web/20150923221031/http://www.dvrpc.org/freight/pdf/2005-02_DERiverDRVPC.pdf |date=September 23, 2015 }}'' [[Delaware Valley Regional Planning Commission]] (January 20, 2005). Retrieved July 14, 2013.</ref><ref name="USACEdeepen">U.S. Army Corps of Engineers. ''[https://www.nap.usace.army.mil/Portals/39/docs/Civil/Deepening/Economic/Updated%20Economic%20Assessment%20of%20Relevant%20Market%20and%20Industry%20Trends%20-%20May%202011.pdf Delaware River Main Channel Deepening Project] {{Webarchive|url=https://web.archive.org/web/20240316201023/https://www.nap.usace.army.mil/Portals/39/docs/Civil/Deepening/Economic/Updated%20Economic%20Assessment%20of%20Relevant%20Market%20and%20Industry%20Trends%20-%20May%202011.pdf |date=March 16, 2024 }} ''. (May 2012). Retrieved July 14, 2013.</ref><ref>Delaware Riverkeeper. ''[http://www.delawareriverkeeper.org/resources/Factsheets/The_Delaware_River_Main_Channel_Deepening_Project.pdf The Delaware River Main Channel Deepening Project: Background] {{webarchive|url=https://web.archive.org/web/20120716222826/http://www.delawareriverkeeper.org/resources/Factsheets/The_Delaware_River_Main_Channel_Deepening_Project.pdf |date=July 16, 2012 }}''. Retrieved July 14, 2013.</ref><ref>{{cite web|url=http://www.njspotlight.com/stories/16/05/23/epic-effort-to-deepen-delaware-river-shipping-channel-nears-end/|title=Epic Effort to Deepen Delaware River Shipping Channel Nears End |website=www.njspotlight.com – NJ Spotlight|date=May 24, 2016 |access-date=May 27, 2016|archive-url=https://web.archive.org/web/20160528110252/http://www.njspotlight.com/stories/16/05/23/epic-effort-to-deepen-delaware-river-shipping-channel-nears-end/|archive-date=May 28, 2016|url-status=live}}</ref><ref>{{cite web|url=http://www.njspotlight.com/stories/16/05/24/murky-bottom-will-deeper-delaware-river-make-philly-more-competitive/|title=Murky Bottom: Will Deeper Delaware River Make Philly More Competitive? |website=www.njspotlight.com – NJ Spotlight|date=May 25, 2016|access-date=May 27, 2016|archive-url=https://web.archive.org/web/20160528110257/http://www.njspotlight.com/stories/16/05/24/murky-bottom-will-deeper-delaware-river-make-philly-more-competitive/|archive-date=May 28, 2016|url-status=live}}</ref>

The Delaware River port complex refers to the ports and energy facilities along the river in the tri-state [[Pennsylvania|PA]]-[[New Jersey|NJ]]-[[Delaware|DE]] [[Delaware Valley]] region. They include the [[Port of Salem]], the [[Port of Wilmington (Delaware)|Port of Wilmington]], the [[Port of Chester (Pennsylvania)|Port of Chester]], the [[Port of Paulsboro]], the [[Port of Philadelphia]] and the [[Port of Camden]]. Combined they create one of the largest shipping areas of the United States. In 2015, the ports of Philadelphia, Camden, and Wilmington handled 100&nbsp;million tons of cargo from 2,243 ship arrivals, and supported 135,000 direct or indirect jobs. The biggest category of imports was fruit, carried by 490 ships, followed by petroleum, and containers, with 410 and 381 ships, respectively. The biggest category of exports was of shipping was containers, with 470 ships.<ref>{{cite web|url=http://www.njspotlight.com/stories/16/05/23/delaware-river-ports-fight-for-market-share-as-dredging-project-nears-completion/|title=Delaware River Ports Fight For Market as Dredging Project Nears Completion |website=www.njspotlight.com – NJ Spotlight|date=May 23, 2016|access-date=May 27, 2016|archive-url=https://web.archive.org/web/20160528110118/http://www.njspotlight.com/stories/16/05/23/delaware-river-ports-fight-for-market-share-as-dredging-project-nears-completion/|archive-date=May 28, 2016|url-status=live}}</ref> In 2016, 2,427 ships arrived at Delaware River port facilities. Fruit ships were counted at 577, petroleum at 474, and containerized cargo at 431.<ref>{{Cite web |url=https://www.maritimedelriv.com/storage/app/media/Publications/Beacon/Issues/Beacon_Winter_2017.pdf |title=Archived copy |access-date=April 9, 2019 |archive-url=https://web.archive.org/web/20190411201441/https://www.maritimedelriv.com/storage/app/media/Publications/Beacon/Issues/Beacon_Winter_2017.pdf |archive-date=April 11, 2019 |url-status=dead }}</ref>

At one time it was a center for petroleum and chemical products and included facilities such as the [[Delaware City Refinery]], the [[Dupont Chambers Works]], Oceanport Terminal at [[Claymont, Delaware|Claymont]], the [[Marcus Hook, Pennsylvania|Marcus Hook]] Refinery, the [[Trainer Refinery]], the [[Port of Paulsboro#Petroleum|Paulsboro Asphalt Refinery]],<ref>{{cite web|url=http://axeonsp.com/manufacturing/refinery/|title=Paulsboro Refinery|date=26 June 2013|access-date=April 11, 2019|archive-url=https://web.archive.org/web/20150622112717/http://axeonsp.com/manufacturing/refinery/|archive-date=June 22, 2015|url-status=usurped}}</ref><ref>{{cite news |url=https://www.bloomberg.com/news/articles/2017-02-03/trump-plans-road-building-as-biggest-u-s-asphalt-plant-shuts |title=America's Biggest Asphalt Plant Is Shutting When the Country Might Need It Most |first=Robert |last=Tuttle |publisher=Bloomberg News |date=February 3, 2017 |access-date=February 4, 2017 |archive-url=https://web.archive.org/web/20170203214727/https://www.bloomberg.com/news/articles/2017-02-03/trump-plans-road-building-as-biggest-u-s-asphalt-plant-shuts |archive-date=February 3, 2017 |url-status=live }}</ref><ref>{{cite news |url=https://www.reuters.com/article/us-usa-refinery-asphalt-idUSKBN1522XE |title=Axeon plans to shutter New Jersey asphalt refinery: sources |first=Jarrett |last=Renshaw |work=Reuters |date=January 18, 2017 |access-date=February 4, 2017 |archive-url=https://web.archive.org/web/20170205101140/http://www.reuters.com/article/us-usa-refinery-asphalt-idUSKBN1522XE |archive-date=February 5, 2017 |url-status=live }}</ref> [[Port of Paulsboro|Paulsboro Refinery]], [[Eagle Point, New Jersey|Eagle Point]] Refinery, and Sunoco Fort Mifflin. As of 2011, [[crude oil]] was the largest single commodity transported on the Delaware River, accounting for half of all annual cargo tonnage.<ref name="USACEdeepen" /><ref>American Waterways. ''[http://www.americanwaterways.com/index/New_Jersey_OnePager.pdf New Jersey A key link in the nation's import/export economy]{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}''. Retrieve July 26, 2013.</ref>

===Crossings===
{{Main|List of crossings of the Delaware River}}

The Delaware River is a major barrier to travel between [[New Jersey]] and [[Pennsylvania]]. Most of the larger bridges are tolled only westbound, and are owned by the [[Delaware River and Bay Authority]], [[Delaware River Port Authority]], [[Burlington County Bridge Commission]] or [[Delaware River Joint Toll Bridge Commission]].

==Environmental issues==
===New York City water supply===
{{further|New York City water supply system}}

After [[New York City]] built 15 reservoirs to supply water to the city's growing population, it was unable to obtain permission to build an additional five reservoirs along the Delaware River's tributaries. As a result, in 1928 the city proposed to draw water from the Delaware River, putting them in direct conflict with villages and towns across the river in [[Pennsylvania]] which were already using the Delaware for their water supply. Additionally, the [[Government of New Jersey]] raised concerns that New York's water diversions might hinder New Jersey's future development of dams and [[hydropower]]; that the [[water quality]] of the river would be impacted, due to reduced flows of fresh water; and that its [[Riparian water rights|riparian rights]] would be diminished. New Jersey filed suit against New York State and New York City, with the [[Government of Pennsylvania]] intervening in the case to protect its interests. In 1931 the [[U.S. Supreme Court]] decided that New York could draw water from the Delaware tributaries, subject to the laws of [[United States Congress|Congress]] and regulation by the [[United States Army Corps of Engineers|US Army Corps of Engineers]].<ref>United States Supreme Court. ''New Jersey v. New York,'' {{ussc|283|36|1931|el=no}}</ref> New York City was allowed to draw {{convert|440|e6USgal|m3}} of water a day from the Delaware and its upstream tributaries,{{Citation needed|date=March 2025}} going on to build three large reservoirs and the [[Delaware Aqueduct]] they feed.

===Pollution===
The Delaware River has been attached to areas of high [[pollution]]. The Delaware River in 2012 was named the 5th [[List of most-polluted rivers|most polluted river]] in the United States, explained by PennEnvironment<ref name="BucksLocalNews2012">{{cite news |title=Environmental group: Delaware River tops list of most polluted waterways |url=https://www.buckslocalnews.com/news/environmental-group-delaware-river-tops-list-of-most-polluted-waterways/article_b94c90d5-a5c1-5c8e-b39d-2319fa2a511a.html |work=Bucks Local News |date=Mar 29, 2012 |access-date=January 28, 2020 |archive-url=https://web.archive.org/web/20200128175024/https://www.buckslocalnews.com/news/environmental-group-delaware-river-tops-list-of-most-polluted-waterways/article_b94c90d5-a5c1-5c8e-b39d-2319fa2a511a.html |archive-date=January 28, 2020 |url-status=live }}</ref> and Environment New Jersey.<ref name="Augenstein2012">{{cite news |last1=Augenstein |first1=Seth |title=Delaware River is 5th most polluted river in U.S., environmental group says |url=https://www.nj.com/news/2012/04/delaware_river_is_5th_most_pol.html |access-date=March 30, 2019 |work=NJ.com News |date=April 5, 2012 |archive-url=https://web.archive.org/web/20200128180116/https://www.nj.com/news/2012/04/delaware_river_is_5th_most_pol.html |archive-date=January 28, 2020 |url-status=dead }}</ref> The activist groups claim that there is about 7–10&nbsp;million pounds of toxic chemicals flowing through the waterways due to dumping by DuPont Chambers Works. PennEnvironment also claims that the pollutants in the river can cause birth defects, infertility among women, and have been linked to cancer.<ref name="BucksLocalNews2012" />

In 2015, the [[United States Environmental Protection Agency|EPA]] saw the Delaware River as a concern for mass pollution especially in the Greater Philadelphia and Chester, Pennsylvania area. The EPA was involved after accusations that the river met standards made illegal by the [[Clean Water Act]]. In complying with the Clean Water Act, the EPA involved the Delaware County Regional Water Authority (DELCORA) where they set up a plan to spend around $200&nbsp;million to help rid the waterway of about 740&nbsp;million gallons of sewage and pollution. DELCORA was also fined about $1.4&nbsp;million for allowing the Delaware River to have so much pollution residing in the river in the first place and for not complying with the Clean Water Act.<ref>{{cite web|title=Settlement to Improve Water Quality in Delaware River, Philadelphia-Area Creeks|work=U.S. EPA Region 3 Water Protection Division|date=August 20, 2015|url=https://www.epa.gov/pa/settlement-improve-water-quality-delaware-river-philadelphia-area-creeks|access-date=January 28, 2020|archive-url=https://web.archive.org/web/20200128180617/https://www.epa.gov/pa/settlement-improve-water-quality-delaware-river-philadelphia-area-creeks|archive-date=January 28, 2020|url-status=live}}</ref>

Part of the Clean Water Act explains how conditions of the river should be stable enough for human fishing and swimming.{{Citation needed|date=March 2023}}  Even though the river has had success with the cleanup of pollution, the Delaware River still does not meet that standard of swimmable or fishable conditions in the Philadelphia/Chester region.

In March 2023, [[2023 Delaware River chemical spill|a pipe rupture at a Trinseo chemical plant]] in [[Bristol, Pennsylvania]], released over 8,000 gallons of [[latex]] finishing material into the [[Mill Creek (Delaware River tributary)|Otter Creek tributary]], leading to a water advisory in [[Philadelphia]].<ref>{{Cite web |last=Hanna |first=Maddie |title=Philly residents advised to drink bottled water Sunday afternoon following chemical spill, officials say |url=https://www.inquirer.com/news/philadelphia-water-department-delaware-river-chemical-spill-20230326.html |url-status=live |archive-url=https://web.archive.org/web/20230326154840/https://www.inquirer.com/news/philadelphia-water-department-delaware-river-chemical-spill-20230326.html |archive-date=2023-03-26 |access-date=2023-03-26 |website=[[The Philadelphia Inquirer]] |date=March 26, 2023 |language=en}}</ref>

===Flooding===
With the failure of the dam project to come to fruition, the lack of flood control on the river left it vulnerable, and it has experienced a number of serious flooding events as the result of snow melt or rain run-off from heavy rainstorms. Record flooding occurred in August 1955, in the aftermath of the passing of the remnants of two separate hurricanes over the area within less than a week: first [[Hurricane Connie]] and then [[Hurricane Diane]], which was, and still is, the wettest tropical cyclone to have hit the northeastern United States. The river gauge at [[Riegelsville, Pennsylvania|Riegelsville]], Pennsylvania recorded an all-time record crest of {{convert|38.85|ft}} on August 19, 1955.

More recently, moderate to severe flooding has occurred along the river. The same gauge at Riegelsville recorded a peak of {{convert|30.95|ft}} on September 23, 2004, {{convert|34.07|ft}} on April 4, 2005, and {{convert|33.62|ft}} on June 28, 2006, all considerably higher than the flood stage of {{convert|22|ft}}.<ref>[https://nj.usgs.gov/special/flood0606/ USGS] {{webarchive|url=https://web.archive.org/web/20070213212133/http://nj.usgs.gov/special/flood0606/|date=February 13, 2007}}
See Also: [http://www.state.nj.us/drbc/Flood_Website/events.htm State of New Jersey: Recent flooding events in the Delaware River basin] {{webarchive|url=https://web.archive.org/web/20080916094959/http://www.state.nj.us/drbc/Flood_Website/events.htm |date=September 16, 2008 }}</ref>

Since the upper Delaware basin has few population centers along its banks, flooding in this area mainly affects natural unpopulated flood plains. Residents in the middle part of the Delaware basin experience flooding, including three major floods in the three years (2004–2006) that have severely damaged their homes and land. The lower part of the Delaware basin from Philadelphia southward to the Delaware Bay is tidal and much wider than portions further north, and is not prone to river-related flooding (although tidal surges can cause minor flooding in this area).

The [[Delaware River Basin Commission]], along with local governments, is working to try to address the issue of flooding along the river. As the past few years have seen a rise in catastrophic floods, most residents of the river basin feel that something must be done. The local governments have worked in association with FEMA to address many of these problems, however, due to insufficient federal funds, progress is slow.<ref>Delaware River Basin Commission (July 20, 2005). [http://www.state.nj.us/drbc/Flood_Website/10ptsJuly2005.pdf "Delaware River Basin Commission's Role in Flood Loss Reduction Efforts."] {{webarchive|url=https://web.archive.org/web/20060818133339/http://www.state.nj.us/drbc/Flood_Website/10ptsJuly2005.pdf |date=August 18, 2006 }} West Trenton, NJ.</ref>

===Oil spills===
A number of [[oil spill]]s have taken place in the Delaware over the years.<ref>{{cite web
| date = November 3, 2005
| url = http://www.ocean.udel.edu/oilspill/
| title = Athos 1 Oil Spill
| publisher = University of Delaware Sea Grant Program
| access-date = April 29, 2006
| archive-url = https://web.archive.org/web/20060427224449/http://www.ocean.udel.edu/oilspill/
| archive-date = April 27, 2006
| url-status = dead
}}</ref><ref>{{cite web
| date = December 16, 2004
| url = http://www.ocean.udel.edu/oilspill/Grandeagle.html
| title = 1985 Grand Eagle Oil Spill
| publisher = University of Delaware Sea Grant Program
| access-date = April 29, 2006
| archive-url = https://web.archive.org/web/20060418210759/http://www.ocean.udel.edu/oilspill/Grandeagle.html
| archive-date = April 18, 2006
| url-status = dead
}}</ref><ref>{{cite web
| date = December 8, 2004
| url = http://www.ocean.udel.edu/oilspill/PresidenteRiveraSpill.html
| title = Presidente Rivera Spill – June 24,&nbsp;1989
| publisher = University of Delaware Sea Grant Program
| access-date = April 29, 2006
| archive-url = https://web.archive.org/web/20060619053228/http://www.ocean.udel.edu/oilspill/PresidenteRiveraSpill.html
| archive-date = June 19, 2006
| url-status = dead
}}</ref>

* January 31, 1975: around {{convert|11,172,000|USgal|m3}} of crude oil spilled from the ''Corinthos'' tanker
* September 28, 1985: {{convert|435,000|USgal|m3}} of crude oil spilled from the ''Grand Eagle'' tanker after running aground on [[Marcus Hook Bar]]
* June 24, 1989: {{convert|306,000|USgal|m3}} of crude oil spilled from the ''Presidente Rivera'' tanker after running aground on [[Claymont Shoal]]
* November 26, 2004: {{convert|265,000|USgal|m3}} of crude oil spilled from the ''Athos 1'' tanker; the tanker's hull had been punctured by a submerged, discarded anchor at the [[Port of Paulsboro]]. In 2020, the [[CITGO Asphalt Refining Co. v. Frescati Shipping Co.|Supreme Court ruled]] that [[Citgo]] had failed to provide a safe berth for the vessel and was therefore jointly responsible for clean up costs. The company was ordered to pay $143&nbsp;million.

===Atlantic sturgeon===
The [[National Marine Fisheries Service]] is considering designating sixteen rivers as endangered habitat for the [[Atlantic sturgeon]] which would require more attention to be given to uses of the rivers that affect the fish.<ref>{{cite web|url=http://www.njspotlight.com/stories/16/06/07/feds-move-to-protect-endangered-atlantic-sturgeon-in-delaware-river/|title=Feds Move to Protect Endangered Atlantic Sturgeon in Delaware River - NJ Spotlight|website=www.njspotlight.com|date=June 8, 2016|access-date=June 11, 2016|archive-url=https://web.archive.org/web/20160611104516/http://www.njspotlight.com/stories/16/06/07/feds-move-to-protect-endangered-atlantic-sturgeon-in-delaware-river/|archive-date=June 11, 2016|url-status=dead}}</ref>

===National Wild and Scenic River===
The river is part of the [[National Wild and Scenic Rivers System]].

==See also==
{{portal|Delaware}}
* [[Geography of Pennsylvania]]
* [[List of municipalities on the Delaware River]]
* [[List of crossings of the Delaware River]]
* [[List of rivers of Delaware]]
* [[List of rivers of New Jersey]]
* [[List of rivers of New York]]
* [[List of rivers of Pennsylvania]]
* [[List of most-polluted rivers]]
* [[Partnership for the Delaware Estuary]]
* [[Upper Delaware Scenic and Recreational River]]

==Citations==
{{Reflist}}

==General and cited references==
* {{Cite book |last=Brooks|first=Victor|title=How America Fought Its Wars |location=New York |publisher=Da Capo Press |year=1999 |isbn=1-58097-002-8 |url=https://books.google.com/books?id=3YhCswEACAAJ |ref=brooks1999}}
* [http://www.55flood.com Devastation on the Delaware: Stories and Images of the Deadly Flood of 1955] {{Webarchive|url=https://web.archive.org/web/20210514170258/https://55flood.com/ |date=May 14, 2021 }} (2005, [http://www.wordforgebooks.com Word Forge Books] {{Webarchive|url=https://web.archive.org/web/20210418112021/https://wordforgebooks.com/ |date=April 18, 2021 }}, Ferndale, PA) The only comprehensive documentary of this weather disaster in the Delaware River Valley.
* {{Cite journal |last=Leach |first=Josiah Granville |year=1902 |title=Commodore John Hazlewood, Commander of the Pennsylvania Navy in the Revolution |journal=The Pennsylvania Magazine of History and Biography |volume=26 |issue=1 |pages=1–6 |publisher=The Historical Society of Pennsylvania |jstor=20086007 |ref=leach02}}
* {{Cite book |last=McGeorge |first=Wallace |year=1905 |title=The Battle of Red Bank, Resulting in the Defeat of the Hessians and the Destruction of the British Frigate Augusta, Oct. 22 and 23, 1777 |url=https://archive.org/details/battleofredbankr00mcge |location=Camden, New Jersey |publisher=Sinnickson Chew, Printers |ref=mcgeorge1905}}
* {{Cite book |last=Savas |first=Theodore |title=Guide to the Battles of the American Revolution |publisher=Savas Beatie |year=2006 |isbn=1-932714-12-X |url=https://books.google.com/books?id=KRRSfy7eVoIC |author6=Theodore P. Savas |ref=savas2006}}

==External links==
{{Commons category}}
* [https://www.delawareriverkeeper.org/ Delaware Riverkeeper Network]
* [http://www.nj.gov/drbc/ Delaware River Basin Commission]
* [http://towmasters.files.wordpress.com/2011/01/vrs_delbayriv_manual_2008.pdf Delaware River Vessel Reporting System]
* [https://www.nps.gov/dewa/index.htm National Park Service: Delaware Water Gap National Recreation Area]
* [https://www.nps.gov/upde/index.htm National Park Service: Upper Delaware Scenic & Recreational River]
* [https://www.nps.gov/lode/index.htm National Park Service: Lower Delaware Wild & Scenic River]
* [https://waterdata.usgs.gov/nj/nwis/current/?type=flow U.S. Geological Survey: NJ stream gaging stations]
* [https://nwis.waterdata.usgs.gov/ny/nwis/current/?type=flow U.S. Geological Survey: NY stream gaging stations]
* [https://nwis.waterdata.usgs.gov/pa/nwis/current/?type=flow U.S. Geological Survey: PA stream gaging stations]
* [https://eada.lib.umd.edu/text-entries/founding-of-new-sweden/#colophon: Early Americas Digital Archive]

===Historical content===
* [http://digitallibrary.hsp.org/index.php/Detail/Object/Show/object_id/3936 Marine Railway and Sectional Floating Dry Dock, Delaware River, Philadelphia, 1893 by D.J. Kennedy, Historical Society of Pennsylvania] {{Webarchive|url=https://web.archive.org/web/20121119201427/http://digitallibrary.hsp.org/index.php/Detail/Object/Show/object_id/3936 |date=November 19, 2012 }}
* [http://digitallibrary.hsp.org/index.php/Detail/Object/Show/object_id/3931 Winter on the River Delaware, 1856. Shows "U.S.S. Powhatan" by D.J. Kennedy, HSP] {{Webarchive|url=https://web.archive.org/web/20120507180403/http://digitallibrary.hsp.org/index.php/Detail/Object/Show/object_id/3931 |date=May 7, 2012 }}
* [https://www.loc.gov/item/2003623407/ "Map of the South River in New Netherland"] from c. 1639 via the [[World Digital Library]]
* [https://web.archive.org/web/20120610193646/http://www.delawareriverkeeper.org/resources/Reports/SocioeconomicValueoftheDRB_UDELdraftreport.pdf Socioeconomic Value of the Delaware River Basin in Delaware, New Jersey, New York, and Pennsylvania]

===Encyclopedias===
* {{Cite Collier's|wstitle=Delaware (river)|display=Delaware, a river of the United States|short=x}}
* {{Cite NSRW|wstitle=Delaware River|short=x}}
* {{Cite NIE|wstitle=Delaware (river)|display=Delaware. A river of the Eastern United States|short=x}}

{{Delaware River and Delaware Bay}}
{{NYCwater}}
{{Authority control}}

[[Category:Delaware River| ]]
[[Category:Borders of Delaware]]
[[Category:Borders of Maryland]]
[[Category:Borders of New Jersey]]
[[Category:Borders of New York (state)]]
[[Category:Borders of Pennsylvania]]
[[Category:Catskill/Delaware watersheds]]
[[Category:Philadelphia metropolitan area]]
[[Category:Delaware Water Gap National Recreation Area]]
[[Category:Rivers of Bucks County, Pennsylvania]]
[[Category:Rivers of Burlington County, New Jersey]]
[[Category:Rivers of Camden County, New Jersey]]
[[Category:Rivers of Delaware]]
[[Category:Rivers of Delaware County, New York]]
[[Category:Rivers of Gloucester County, New Jersey]]
[[Category:Rivers of Hunterdon County, New Jersey]]
[[Category:Rivers of Maryland]]
[[Category:Rivers of Mercer County, New Jersey]]
[[Category:Rivers of Monroe County, Pennsylvania]]
[[Category:Rivers of New Castle County, Delaware]]
[[Category:Rivers of New Jersey]]
[[Category:Rivers of New York (state)]]
[[Category:Rivers of Orange County, New York]]
[[Category:Rivers of Pennsylvania]]
[[Category:Rivers of Philadelphia]]
[[Category:Rivers of Pike County, Pennsylvania]]
[[Category:Rivers of Salem County, New Jersey]]
[[Category:Rivers of Sullivan County, New York]]
[[Category:Rivers of Wayne County, Pennsylvania]]
[[Category:Rivers of Delaware County, Pennsylvania]]
[[Category:Rivers of Northampton County, Pennsylvania]]
[[Category:Rivers of Sussex County, New Jersey]]
[[Category:Rivers of Warren County, New Jersey]]
[[Category:Wild and Scenic Rivers of the United States]]