USACE Microbial Source Tracking of the Bronx River Watershed

In 2006, The United States Army Corps of Engineers, New York District (USACE) subcontracted Princeton Hydro, LLC and Monmouth University to perform a Microbial Source Tracking study (MST) of the Bronx River watershed by using Antibiotic Resistance Analysis (ARA). The watershed includes nearly 1.8 million people and encompasses 36,096 acres in 13 municipalities of Westchester County.

Princeton Hydro partnered with Monmouth University to perform the following tasks:
• Spring, summer and fall pathogen surveys
• Validation of the Monmouth County ARA database
• Creation of a Bronx River ARA Database
• Evaluation of land uses and analytical data for pathogens and nutrient loading
• Evaluation of stormwater management problem areas
• Best Management Practices (BMP) recommendations

While geese, pets, and horses contribute to the bacteria counts in the Bronx River, the impacts from 1.8 million people are a likely dominant source. This population also relies upon aging infrastructure and combined conveyance systems for stormwater and wastewater that were built in 1900. This infrastructure is undersized, fraught with leaks, and is subject to breaks, illicit connections, direct discharges, and combined sewer outfalls. Stormwater management in the watershed consists mainly of street drains and storm sewer connections to the river and its tributaries, with little or no retention.

Potential BMPs recommended for the Bronx River included source control via some of the following:
• Regulatory Activities
• Redevelopment and Green Building
• Stormwater Management BMPs
• Infrastructure Remediation

Water quality improvement recommendations included addressing illicit connection problems and reducing stormwater loading of bacteria. These recommendations were designed in concert with the project partners and looked for real world, achievable solutions towards river improvement.