Patapsco River

Template:Short description Template:Use American English Template:Use dmy dates Template:Infobox river

File:Inner Harbor from the Baltimore Aquarium.jpg

The Inner Harbor viewed from the Baltimore Aquarium

Liberty Reservoir

Volunteers at a community cleanup of Herbert Run, a tributary of the Patapsco River running through Arbutus, Maryland

The Patapsco River (Template:IPAc-en Template:Respell {{#if:En-patapsco.ogg|{{#ifexist:Media:En-patapsco.ogg|<phonos file="En-patapsco.ogg"> </phonos>|{{errorTemplate:Main other|Audio file "En-patapsco.ogg" not found}}Template:Category handler}}}}) mainstem is a Template:Convert<ref name="NHD">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> river in central Maryland that flows into the Chesapeake Bay. The river's tidal portion forms the harbor for the city of Baltimore. With its South Branch, the Patapsco forms the northern border of Howard County, Maryland. The name "Patapsco" is derived from the Algonquian pota-psk-ut, which translates to "backwater" or "tide covered with froth".<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

HistoryEdit

Captain John Smith was the first European to explore the river, noting it on his 1612 map as the Bolus River. The "Red river", named after the clay color, is considered the "old Bolus", as other branches were also labeled Bolus on maps.<ref>Template:Cite book</ref> As the river was not navigable beyond Elkridge, it was not a significant path of commerce; in 1723, only one ship was listed as serving the northern branch, and four others operating around the mouth.<ref>Template:Cite book</ref>

The first land record regarding Parr's Springs, the source of the South Branch, dates from 1744, when John Parr laid out a Template:Convert tract he called Parr's Range. During the Civil War, Parr's Spring was a stop for the Army of the Potomac's Brig. Gen. David M. Gregg's cavalry, on 29 June 1863, while en route to Gettysburg, Pennsylvania.<ref>Template:Cite book</ref> Parr's Spring was dug to form a Template:Convert pond in the 1950s, filled by seven spring heads that form the headwaters of the South Branch of the Patapsco River.<ref>Template:Cite news</ref>

Beginning in the 1770s, the Patapsco River became the center of Maryland industrialization.<ref name=Travers>Template:Cite book</ref> Milling and manufacturing operations abounded along the river throughout the eighteenth and nineteenth centuries, generally powered by small dams. The Baltimore and Ohio Railroad's original main line was constructed in 1829 west along the Patapsco Valley; the nation's first railroad, the route remains, though much altered. Many railroad bridges were built in the valley, including the Thomas Viaduct, which is still in use, and the Patterson Viaduct, now in ruins. The 1907 hydropower Bloede's Dam powered flour mills.

An 1868 flood washed away 14 houses and killed 39 people around Ellicott City. A 1923 flood topped bridges. In 1952, an Template:Cvt wall of water swept the shops of Ellicott City. A 1956 flood severely damaged the Bartigis Brothers plant.<ref>Template:Cite news</ref> In 1972, rainfall from the remnants of Hurricane Agnes damaged Ellicott City and the Old Main Line. Two died in the July 2016 Maryland flood ravaged Main Street, followed two years later by a May 2018 Maryland flood that took the life of a rescuer.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The mouth of the Patapsco River forms Baltimore Harbor, the site of the Battle of Baltimore during the War of 1812. This is where Francis Scott Key, aboard the British Template:HMS, wrote "The Star-Spangled Banner", a poem later set to music as the national anthem of the United States. Today, a red, white, and blue buoy marks where the ship was anchored.

Bloede's Dam, a hydroelectric dam built in 1906, was on the Patapsco River within Patapsco Valley State Park, a nearly complete barrier to anadromous fish passage. Although a fish ladder was installed in 1992, it blocked five of six native fish species trying to run upstream to spawn.<ref name="Bloede">Template:Cite report</ref> Efforts to remove Bloede's Dam began in the 1980s when nine drowning deaths occurred, and also to restore fish passage to a large portion of the Patapsco River watershed.<ref>Template:Cite news</ref><ref>Template:Cite news</ref> Dam demolition began on 12 September 2018, opening the fishery and creating a rocky rapid for kayaking.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Two dams upstream of Bloede's Dam, Simkins and Union, were removed in 2010.<ref>Template:Cite news</ref><ref name="Cui">Template:Cite journal</ref> The removal of Bloede's Dam leaves Daniels Dam, Template:Convert upstream, as the last remaining dam along the mainstem Patapsco River.<ref name="Bloede" />

In the early hours of 26 March 2024, the Template:Convert Francis Scott Key Bridge, which carried Interstate 695 over the Patapsco River, was struck by a container ship and partially collapsed into the river.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

CourseEdit

The Template:Convert<ref name="NHD" /> South Branch rises at Parr's Spring, where Howard County, Carroll, Frederick, and Montgomery counties meet. The latter begins at elevation Template:Convert on Parr's Ridge, just south of Interstate 70 and east of Ridge Road (Highway 27), Template:Convert south of Mount Airy, Maryland.<ref name="NHD" /> The South Branch Patapsco River traces the southern boundary of Carroll County and the northern boundary of Howard County.

The North Branch flows Template:Convert<ref name="NHD" /> southward from its origins in Carroll County. Liberty Dam and its reservoir on the North Branch are major components of the Baltimore City water system.<ref>Baltimore County Department of Environmental Protection and Resource Management. Towson, MD. "Patapsco River Watershed." 13 July 2009.</ref>

The Patapsco River mainstem begins at the confluence of the North and South Branches, near Marriottsville, about Template:Convert west of downtown Baltimore. Through most of its length, the Patapsco is a minor river flowing mostly through a narrow valley. Patapsco Valley State Park extends along Template:Convert of the Patapsco and its branches, encompassing Template:Convert in five areas. The river cuts a gorge 100 to 200 feet (35–70 m) deep within the park, with rocky cliffs and tributary waterfalls.

The last Template:Convert, form a large tidal estuary inlet of Chesapeake Bay. Two lobes of the harbor deviate from the "mainstem" harbor: the Middle Branch Patapsco River, into which Gwynns Falls; and the Northwest Branch Patapsco River, into which Jones Falls flows. The inner part of this estuary provides the harbor of Baltimore. Thoms Cove is further down the main harbor. The Patapsco estuary is south of the Back River and north of the Magothy River.

TributariesEdit

The Patapsco has a watershed (including the water surface) of Template:Convert.<ref name="Cui" /> Template:Div col

Deep Run (Carroll County)
Board Run (Baltimore County)
Roaring Run (Carroll County)
Liberty Reservoir (Carroll/Baltimore Counties)
Piney Run (Carroll County)
Keysers Run (Baltimore County)
Beaver Run (Carroll County)
Norris Run (Baltimore County)
Timber Run (Baltimore County)
Middle Run (Carroll County)
Morgan Run (Carroll County)
Locust Run (Baltimore County)
Snowdens Run (Carroll County)
Falls Run (Baltimore County)
South Branch Patapsco River
Davis Branch (Howard County)
Brice Run (Baltimore County)
Bens Run (Baltimore County)
Cedar Branch (Baltimore County)
Miller Run (Baltimore County)
Sucker Branch (Howard County)
Tiber River (Howard County)
Cooper Branch (Baltimore County)
Bonnie Branch (Howard County)
Sawmill Branch (Baltimore County)
Cascade Falls (Howard County)
Soapstone Branch (Baltimore County)
Rockburn Branch (Howard County)
Deep Run (Howard/Anne Arundel County)
Stony Run (Anne Arundel County)
Herbert Run (Baltimore County)
Holly Creek (Anne Arundel County)
Middle Branch to Gwynns Falls (Baltimore City)
Northwest Harbor to Jones Falls (Baltimore City)
Colgate Creek (Baltimore City)
Curtis Creek (Baltimore City)
Bear Creek (Baltimore County)
Cox Creek (Anne Arundel County)
Stoney Creek (Anne Arundel County)
Rock Creek (Anne Arundel County)
Old Road Bay (Baltimore County)
Bodkin Creek (Anne Arundel County)

Template:Div col end

Ecology and conservationEdit

The removal of Bloede's Dam in September 2018, opened up Template:Convert of the Patapsco River watershed, which will potentially restore spawning runs of at least six species of native anadromous fish: alewife (Alosa pseudoharengus), blueback herring (Alosa aestivalis), American shad (Alosa sapidissima), hickory shad (Alosa mediocris), striped bass (Morone saxatilis), sea lamprey (Petromyzon marinus), as only one species, sea lamprey, were found using the Bloede's Dam fish ladder in 2012.<ref name=Bloede/> One catadromous species would likely also benefit, the American eel (Anguilla rostrata), a fish species that lives in freshwater and migrates to the ocean to breed. The Bloede's Dam removal project was led by American Rivers and the Maryland Department of Natural Resources.<ref name=Bloede/>

Now that Bloede's Dam has been removed, removal of Daniels Dam upstream on the mainstem Patapsco River would open to anadromous fishes the remaining Template:Convert of Patapsco River mainstem, the entire Template:Convert length of the South Branch Patapsco River, Template:Convert of the North Branch Patapsco River up to the Liberty Dam, and many of these rivers' tributaries.<ref name=NHD/>

Water qualityEdit

The eastern portion of the Patapsco River is in a highly urbanized area and is subject to extensive stormwater runoff and other forms of water pollution. The Maryland Department of the Environment has identified the Lower North Branch as containing high levels of heavy metals (chromium, arsenic, cadmium, copper, mercury, nickel, lead, selenium, and zinc), as well as phosphorus, fecal coliform bacteria, and PCBs.<ref> {{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The Piney Run Reservoir on the South Branch of the Patapsco is polluted by excess levels of phosphorus and sediment.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Environmental nonprofit organizations, such as The Friends of Patapsco Valley & Heritage Greenway, Inc. (PHG), lead clean-up efforts by the residents of surrounding communities. From 2006 to 2012, PHG volunteers participated in 183 stream clean-ups, removing 264 tons of trash from the streams of the Patapsco Valley watershed.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

RecreationEdit

Recreational swimming is possible in areas of the Patapsco River, sometimes involving rope swings, inner tubing, and wading. The river also serves as a venue for rafting. The Patapsco is also great for fishing. The MD DNR stocks parts of Patapsco State Park in the early spring and offers some pretty decent trout fishing. The Northern Snakehead has also made the Patapsco their home. They can be found from historic Ellicott City to the harbor.

CrossingsEdit

This is a list of all crossings of the main stem of the Patapsco River, as well as its two downstream short branches, the Middle Branch and Northwest Branch. Listings start downstream and continue upstream to the sources of the rivers.

Image	Crossing	Carries	Location	Opened	Notes
Anne Arundel County – Baltimore County
File:The Francis Scott Key Bridge (Baltimore).jpg	Francis Scott Key Bridge	Template:Jct	Baltimore	1977–2024	Collapsed after being struck by a container ship on 26 March 2024
File:2016-08-12 15 49 22 View north along Interstate 895 (Baltimore Harbor Tunnel) in Baltimore City, Maryland.jpg	Baltimore Harbor Tunnel	Template:Jct	Baltimore	1957	$4.00 toll
File:Fort McHenry Tunnel Bore 2.jpg	Fort McHenry Tunnel	Template:Jct	Baltimore	1985	Crosses Northwest Branch only; $4.00 toll
File:I-395-Downtown Baltimore.JPG	Hanover Bridge	Template:Jct	Baltimore		Crosses Middle Branch only
	Spring Garden Swing Bridge	Western Maryland Railway	Baltimore	citation	CitationClass=web }}</ref>	Crosses Middle Branch only
	Ridgleys Cove interchange	Template:Jct Template:Jct	Baltimore		Crosses Middle Branch only
	Light rail bridge	Baltimore Light RailLink	Baltimore		Crosses Middle Branch only
	Hanover and Potee Street Bridges	Template:Jct	Baltimore	1973	citation	CitationClass=web }}</ref>
	Curtis Bay Branch Railroad bridge	B&O Curtis Bay Branch	Baltimore
	Patapsco Avenue bridge	Patapsco Avenue	Brooklyn, Baltimore	1961
	I-895 bridge near South West Area Park	Template:Jct	Baltimore Highlands	1958	citation	CitationClass=web }}</ref>
	Central Light Rail bridge	Baltimore Light Rail	Baltimore Highlands	1908	Previously used for the Baltimore and Annapolis Railroad
	Old Annapolis Road bridge	Template:Jct	Baltimore Highlands
	BW Parkway bridge	Template:Jct	Baltimore Highlands	1948	citation	CitationClass=web }}</ref>
	Hammonds Ferry Road bridge	Hammonds Ferry Road	Linthicum Lansdowne	1961
	Baltimore Beltway bridge	Template:Jct	Linthicum Lansdowne	1958	citation	CitationClass=web }}</ref>
	Northeast Corridor bridge	Amtrak Northeast Corridor	Linthicum Halethorpe
	I-195 bridge	Template:Jct	Elkridge Halethorpe	1988
Howard County – Baltimore County
	I-895 bridge	Template:Jct	Elkridge Relay	1973	On/off ramp bridges flank US 1 bridge to north and south
	Patapsco River Bridge	Template:Jct	Elkridge Relay	1915	citation	CitationClass=web }}</ref>
File:Thomas-viaduct-2011.jpg	Thomas Viaduct	B&O Capital Subdivision	Elkridge Relay	1835	World's largest multiple arched bridge. Named after Philip E. Thomas.<ref>{{#invoke:citation/CS1\|citation	CitationClass=web }}</ref>
	I-95 bridge	Template:Jct	Elkridge Relay	1968
	Gun Road bridge	Gun Road	Relay		Patapsco Valley State Park access only
File:Patapsco Swinging Bridge 2020a.jpg	Patapsco Swinging Bridge	Swinging Bridge Trail	Ilchester	2006	Pedestrian bridge connecting River Road to Grist Mill Trail
File:Patterson Viaduct Footbridge 2020a.jpg	Patterson Viaduct	Grist Mill Trail	Ilchester	2006	Former rail bridge opened 1829, destroyed 1868, and rebuilt 1869; new footbridge built on abutments of prior rail bridge
File:Ilchester Tunnel.JPG	Ilchester Bridge	Old Main Line Subdivision	Ilchester	1903
File:Ilchester Road Bridge 2020.jpg	Ilchester Road bridge	Ilchester Road	Ilchester		citation	CitationClass=web }}</ref>
File:Railroad bridge at entrance to ellicott city.jpg	Main Street Bridge	Template:Jct	Ellicott City Oella	1914
	Baltimore National Pike Bridge	Template:Jct	Ellicott City Catonsville	1936	citation	CitationClass=web }}</ref>
	I-70 bridge	Template:Jct	Ellicott City Catonsville	1966
	Hollifield Bridge	Old Frederick Road	Daniels	1934
File:Daniels Area 78.JPG	Daniels bridge	Old Main Line Subdivision	Daniels
	Eureka bridge	Old Main Line Subdivision	Mt. Airy
	MD 125 bridge	Template:Jct	Woodstock	1981
Patapsco River North Branch-South Branch confluence