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Chemical Indicators Signal High Levels of Bacteria and Pathogens from Sewage Sources in Baltimore City Waterways (web article)


A report recently released by the Baltimore Sanitary Sewer Oversight Coalition (BSSOC), in conjunction with four Baltimore watershed associations, finds that many urban streams in Baltimore suffer from sewage contamination. The report, authored by Guy Hollyday, chairman of BSSOC, and Christel Cothran, with the Jones Falls Watershed Association, was written to draw attention to the ongoing contamination of City streams, many of which flow through municipal parks and residential areas. The goal of the report is to provide information to help identify ways to better protect our urban waterways from sewage contamination.

Hollyday said, “Citizens should know that at this very moment, as for decades past, we are allowing streams of sewage to flow into our water cources - in part, because historically we have paid such low water and sewer rates. Every time it rains there are places where sewage overflows. There are many problems to address and there is much to do.”

Rolf Halden

Rolf Halden, PhD, PE

The water quality report includes findings from research conducted by Rolf Halden, PhD, PE, assistant professor in the Department of Environmental Health Sciences at the Johns Hopkins Bloomberg School of Public Health, and Daniel Paull, a research intern and graduate student in the Johns Hopkins University Zanvyl Krieger School of Arts & Sciences. Halden’s study, which analyzed water samples from six urban streams, identified several areas where high levels of antimicrobial compounds indicated massive wastewater inputs. Perhaps the study’s most alarming discovery was that the water flowing from Gwynns Run into Gwynns Falls was at times chemically indistinguishable from raw sewage. The study was funded by the Johns Hopkins Center for a Livable Future.

“This report is important because it presents scientific evidence of unhealthy levels of pollution from sewage,” said Dr. Halden. “We’ve known we have sewage problems. This report will help us recognize the opportunities we have to solve them.”

Sewage discharges caused by storm overflows and an aging infrastructure allow untreated human waste and personal care products to flow into local creeks and streams. According to a consent decree with the U.S. Department of Justice, Baltimore City has until 2016 to significantly reduce sewage overflows. The cost of the work, estimated at $1.3 billion, will be paid for by increases in residents’ water and sewer rates.

Each year, there are about 100 overflows into our streams and many more sewage backups into private homes from various causes - sometimes from defects on owners’ properties; sometimes from backups in City mains.

“I hope this report will raise public awareness of potential human health risks, and focus resources and actions to address water quality problems caused by sewage spills,” said Dr. Halden. – Brian Fitzek

Download the report

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Lowe or Tim Parsons at 410-955-6878 or