MIT 4.213J/11.308J Urban Nature and City Design








About the Bronx River
Jurisdictions * History * Ecology


Taken from the Bronx River and Bronx Park Historical Signs, USGS site and DPR Press Release

The river's story began more than 150 million years ago when a waterway, whose origins lie in present day Westchester County, began carving a channel for itself through bedrock on its way towards the Bronx. Geologists believe that the Bronx River once emptied into the Hudson River, which lay to the east of its present location. A huge ice mass blocked the Bronx River's flow during the last Ice Age and forced it to cut a new channel. As the Bronx River meandered on its way, it created a deep gorge before finally emptying out into the East River and Long Island Sound. (5)

"A 40-acre forest in the New York Botanical Garden is situated on the slopes above the river gorge. The forest, thought to be the only forest in New York that was never cleared, is a mixture of eastern hemlock and hardwoods….In the Bronx River hemlock forest, black cherry and black birch are replacing the dying hemlocks.” (6)

“The Bronx River has been altered dramatically over the past 200 years by human impact and industry. In order to create the Bronx River Parkway, workers ‘straightened' the Bronx River, building artificial banks and destroying the natural floodplain. Since bends in a river's flow naturally slow erosion, the Bronx River widened over time as erosion sent silt downstream. The silt choked native plants and new, non-native plants began to thrive, disturbing local wildlife.” (7)

“Industrial pollution and urban sewer discharges have caused debris jams, flooding, excessive storm water runoff, sedimentation, erosion, habitat loss and sewage overflows. The poor water quality of the Bronx River negatively impacts the watershed's value as a recreational, educational, ecological and economic resource.” (8)