Gwynns Falls: West Side Story

In this story series, we explore Baltimore City's four subwatersheds. The Gwynns Falls subwatershed stretches from rural Baltimore County down through the city's western edge.

  • Conservation

The Gwynns Falls is one of four subwatersheds within the City of Baltimore, along with Baltimore Harbor, Jones Falls and Back River. Together, these four areas encompass 194 square miles of land, 454 miles of streams and more than a million residents.

This slim, elongated subwatershed shares its name with the stream that flows southward over about 25 miles from the Glyndon/Reisterstown area of Baltimore County down through the northwest neighborhoods of Baltimore City. Eventually, near the knot of highway at the interchange of Interstate 95 and the Baltimore–Washington Parkway in West Baltimore, the Gwynns Falls stream empties into the Middle Branch of the Patapsco River. From there, it connects to the Chesapeake Bay and the ocean beyond.

At its headwaters, the Gwynns Falls is a skinny, shallow, unassuming little stream tucked away between a gated soccer field at the Sacred Heart Catholic Church and private homes. Almost immediately, it disappears beneath Sacred Heart Lane and then reappears, already slightly wider, moving south through woods that edge the church's property.

Aerial View of a Stream Winding Through the Trees Within a Suburban Area Near a Highway in the Gwynns Falls Subwatershed

The stream runs loosely parallel to Owings Mills Boulevard, passing through the campus of Stevenson University, widening and gaining strength as tributaries like Dead Run and smaller, unnamed streams flow into and are subsumed by it.


Gwynns Falls is named for an early Maryland settler, Richard Gwinn, who established a trading post along the stream in the 1600s. There are no true waterfalls, but the stream does feature areas of rocky rapids that were once called "felles."

Map of the Gwynns Falls Subwatershed Major Waterways: Red Run, Scotts Level Branch, Dead Run, Horsehead Branch, Gwynns Falls, Lake Ashburton and Maidens Choice Run

Some of the Gwynns Falls' larger tributaries include Dead Run, Horsehead Branch, Maidens Choice Run, Red Run and Scotts Level Branch. The Gwynns Falls subwatershed is also home to Lake Ashburton, a reservoir in Hanlon Park. The reservoir was built in the early 1900s as part of Baltimore's municipal water system.

Like the rest of Baltimore City's waterways, the Gwynns Falls first supported the original inhabitants of the Chesapeake region, including the Piscataway, Nanticoke and Susquehannock people, among many others. According to "The Gwynns Falls: Baltimore Greenway to the Chesapeake" by W. Edward Orser, "[t]here is strong evidence that an important trail used by the Susquehannocks traveling from Pennsylvania to the Chesapeake region crossed the Gwynns Falls at two fords, where the stream meets the coastal plain, between today's Wilkens Avenue and Washington Boulevard."

Later, white settlers used the Gwynns Falls for industry.


The development of Baltimore City was largely driven by its streams and rivers. Settlers built mills along the Gwynns Falls and other major streams, using water to power machinery that produced flour, paper, textiles and more.

Map of the Gwynns Falls Subwatershed Neighborhoods: Arlington, Gwynn Oak, Forest Park, Dickeyville, Franklintown, Leakin Park, Violetville, Park Heights, Ashburton, Mondawmin, Mosher, Morrell Park and Westport

Communities developed along the Gwynns Falls because of these early industries. Some of these communities, including Dickeyville and Franklintown, still exist today.

Dickeyville—near Forest Park—is a historic mill town dating back to 1772. Listed on the National Register of Historic Places, the original homes were built for mill workers and their families. Before being called Dickeyville, after a local Irish textile mill owner, the town carried the name Franklinville and, later, Wetheredsville.

What's now Franklintown Road was once a turnpike built in the 1830s to provide a route between the city and outlying farms. A gristmill and a community slowly developed along the turnpike, north of Dead Run. This community became Franklintown, which is also now a registered historic district.

Green Spaces

The Gwynns Falls subwatershed holds two significant green spaces. In Baltimore County, Soldiers Delight Natural Environment Area in Owings Mills features the largest remaining serpentine grassland ecosystem in the eastern United States.

Map of the Gwynns Falls Subwatershed Green Spaces: Soldier's Delight, Villa Nova Park, Powder Mill Park, Hillsdale Park, Irvington Park, Forest Park Golf Course, Hanlon Park, Leakin Park and Carroll Park Golf Course

Baltimore City has an area within the subwatershed that's equally noteworthy. Gwynns Falls Leakin Park is the largest old-growth forest within any East Coast city. At 1,000 acres, it's also one of the largest preserves in a major urban area in the United States. The park is a sanctuary for wildlife, threaded with trails and dotted with historic structures.

Much of Gwynns Falls Leakin Park would have been destroyed by an expressway proposed in the 1960s and 70s to link Interstates 70, 83 and 95. Activists concerned about the proposed expressway's effect on neighborhoods and the environment successfully blocked its development. This permanent halt to plans that were already underway explains both the abrupt end of I-70 in Woodlawn—now a Park-and-Ride and a trailhead for the Gwynns Falls Trail—and the mile-long Highway to Nowhere in West Baltimore, where a vibrant, predominantly Black neighborhood once stood. More than 970 homes and 62 businesses were razed to build the stretch of roadway, which was never finished but displaced approximately 1,500 people.

Today, Gwynns Falls Leakin Park is home to the Carrie Murray Nature Center, named for the mother of legendary Baltimore Oriole Eddie Murray; the Crimea Estate, the former home of the Winans family; a historic iron water wheel; the Carrollton Viaduct; Leon Day Park and more.

Maryland is considering turning Gwynns Falls Leakin Park into a state park, which would make it the first to be located within Baltimore City. The National Aquarium has submitted testimony in support of the Gwynns Falls State Park bill and will continue to back the effort.

Connection Point

Where the Gwynns Falls stream meets and flows into the Middle Branch of the Patapsco, it bears little resemblance to the skinny, shallow, unassuming waterway hidden between a soccer field and private homes in Glyndon.

Here, Gwynnda the Good Wheel of the West does her thing. Since she was installed in the Gwynns Falls at the mouth of the Middle Branch in June 2021—the fourth in Waterfront Partnership's googly-eyed family of Trash Wheels—she's gobbled up an estimated 400 tons of litter and debris each year, preventing it from flowing into the Patapsco and the Bay.

Gwynnda and the other Trash Wheels are just one of the ways that people are stepping up to protect the Gwynns Falls and other waterways that have shaped Baltimore from the beginning and that link the city to the broader Chesapeake Bay watershed and the vast ocean beyond.

Support the National Aquarium

Your gift supports the highest level of animal care and advances research, education and conservation action.