The Gunpowder River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data
The National Map
, accessed April 1, 2011 tidal inlet on the western side of

Chesapeake Bay The Chesapeake Bay ( ) is the largest estuary in the United States. The Bay is located in the Mid-Atlantic region and is primarily separated from the Atlantic Ocean by the Delmarva Peninsula (including the parts: the Eastern Shore of Maryland / ...

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. It is formed by the joining of two freshwater rivers, Gunpowder Falls (often referred to locally as "Big Gunpowder Falls") and Little Gunpowder Falls.

Gunpowder Falls

The Big Gunpowder, long, begins in the extreme southern part of

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

's York County. From there, the Gunpowder flows in a generally southeast direction through the length of

Baltimore County Baltimore County ( , locally: or ) is the third-most populous county in the U.S. state of Maryland and is part of the Baltimore metropolitan area. Baltimore County (which partially surrounds, though does not include, the independent City of ...

past the

Perry Hall Mansion The Perry Hall Mansion is a historic structure located in the area to which it gave its name, Perry Hall, Baltimore County, Maryland, United States. Erected on a hill above the Gunpowder River Valley, the mansion is an excellent example of late ...

and the site of its former plantation until it reaches Joppatowne where it is joined by the Little Gunpowder and the Bird River, becoming simply the "Gunpowder River" once it passes the

Amtrak The National Railroad Passenger Corporation, doing business as Amtrak () , is the national passenger railroad company of the United States. It operates inter-city rail service in 46 of the 48 contiguous U.S. States and nine cities in Canada ...

train bridge that joins

Chase Chase or CHASE may refer to: Businesses * Chase Bank, a national bank based in New York City, New York * Chase Aircraft (1943–1954), a defunct American aircraft manufacturing company * Chase Coaches, a defunct bus operator in England * Chase Co ...

and Joppatowne. The nearby site of old Joppa was an important deep-water seaport, and rival to the port of Baltimore, in colonial American times, until

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the ...

of the Gunpowder River -- caused by upstream development -- made its harbor inaccessible to large ships.

Little Gunpowder Falls

Little Gunpowder Falls, as its name implies, is much smaller than the mainstem Gunpowder Falls. Throughout its length, it forms much of the boundary between eastern Baltimore County and western

Harford County Harford County is located in the U.S. state of Maryland. As of the 2020 census, the population was 260,924. Its county seat is Bel Air. Harford County is included in the Baltimore-Columbia-Towson, MD Metropolitan Statistical Area, which is al ...

until it reaches the Big Gunpowder. The headquarters of the

Gunpowder Falls State Park Gunpowder Falls State Park is a public recreation area comprising six non-contiguous areas covering in northeastern Baltimore County and western Harford County, Maryland. The state park is primarily made up of the stream valleys of the Big and ...

is located in

along the bank of the Little Gunpowder Falls, in the historic

Jerusalem Mill Village Jerusalem Mill Village is a living history museum that spans the 18th through early 20th centuries. One of the oldest and most intact mill villages in the U.S. state of Maryland, Jerusalem is located in Harford County, along the Little Gunpowd ...

. The remainder of the boundary between Baltimore and Harford counties is formed by the Gunpowder River, the tidal

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

of the

formed by the union of Little Gunpowder Falls and the Gunpowder Falls rivers.

Recreation

Both the Gunpowder and Little Gunpowder Falls flow through hilly agricultural and forest land for much of their length. In fact, there are no less than four separate state parks that form

, the largest state park in Maryland. At two points, Gunpowder Falls is dammed to form major

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

s for the

Baltimore metropolitan area The Baltimore–Columbia–Towson Metropolitan Statistical Area, also known as Central Maryland, is a Metropolitan Statistical Area (MSA) in Maryland as defined by the United States Office of Management and Budget (OMB). As of the 2010 Census, t ...

Prettyboy Reservoir Prettyboy Reservoir is a reservoir in northern Baltimore County, Maryland, also known as the Hereford Zone. Even though the reservoir is in the county, the City of Baltimore owns the reservoir and the surrounding land of forested watershed. The ...

and Loch Raven Reservoir. By the time the Gunpowder reaches the Bay, however, it is no longer a rural river, but a suburban river that passes under Interstate 95 and many

bedroom communities A commuter town is a populated area that is primarily residential rather than commercial or industrial. Routine travel from home to work and back is called commuting, which is where the term comes from. A commuter town may be called by many o ...

for Baltimore. Nonetheless, Gunpowder State Park on the Chesapeake Bay may give one the impression that this is still a somewhat remote river. Both streams flow over the

Fall Line A fall line (or fall zone) is the area where an upland region and a coastal plain meet and is typically prominent where rivers cross it, with resulting rapids or waterfalls. The uplands are relatively hard crystalline basement rock, and the coa ...

separating the

Piedmont Plateau The Piedmont is a plateau region located in the Eastern United States. It is situated between the Atlantic coastal plain and the main Appalachian Mountains, stretching from New York in the north to central Alabama in the south. The Piedmont ...

from the Atlantic Coastal Plain just downstream of

US Route 1 U.S. Route 1 or U.S. Highway 1 (US 1) is a major north–south United States Numbered Highway that serves the East Coast of the United States. It runs from Key West, Florida, north to Fort Kent, Maine, at the Canadian border, making ...

. This creates some class III

whitewater Whitewater forms in a rapid context, in particular, when a river's gradient changes enough to generate so much turbulence that air is trapped within the water. This forms an unstable current that froths, making the water appear opaque and ...

opportunities for kayakers and canoeists when the water is reasonably high.

Tributaries

*Minebank Run *Long Green Creek *Sweathouse Run *Haystack Branch *Jennifer Branch *Bean Run *Foster Branch *Taylor Creek *Broad Run

References

External links