Over forty years after implementation of the 1972 Clean Water Act, the Hudson River has made noticeable improvements in water quality. But a new study published in the Journal of Water and Health shows that bacteria resistant to antibiotics still thrive in the river, and they may be linked to untreated sewage.

"Counts of the fecal indicator, Enterococcus, were positively correlated with levels of resistant bacteria, suggesting a shared sewage-associated source," the study states.

The bacteria were predominantly found near Flushing Bay, Newtown Creek, 125th St in Harlem, and Piermont Pier in Rockland County. The study notes that wastewater treatment plants release about 27 billion gallons of raw sewage into the river each year, in what is known as combined-sewer overflow (CSO).

The particular bacteria were found to be resistant to tetracycline, which is used to treat pneumonia, acne, and genital and urinary infections, as well as ampicillin, an antibiotic similar to penicillin that treats bronchitis and pneumonia.

This is the first study that focuses in the Hudson River Estuary (HRE) and documents these antibiotic-resistant bacteria in relation to sewage bacteria in an estuary. Previously, antibiotic-resistant bacteria had been found in the Hudson in 2002, as well as in fifteen other U.S. rivers.

Before the Clean Water Act was enacted, the Hudson River, which is now a recreational destination featuring more than fifty parks, was known for its levels of pollution. "Many people recall being able to look into the Hudson River downstream from the General Motors site in Sleepy Hollow and be able to know what color they were painting the cars that day because of the discharge of polluted waste water into the Hudson," Ned Sullivan, president of the non-profit group Scenic Hudson, told the Rivertowns Daily Voice.

New York Governor Cuomo signed the Sewage Pollution Right to Know Law in 2012, which requires that the public be notified if and when sewage spills occur in NY water. In addition, $2.4 billion will be poured into improving infrastructure to remove 1.5 billion gallons of CSOs by 2030 in New York City. The city also agreed to use porous pavement in parking lots and streets to help reduce runoff.

Coauthor and microbiologist Gregory O'Mullan notes that the study might "provide added incentive to reduce sewage pollution into our waterways."

Source: Suzanne Young, Andrew Juhl, Gregory D. O'Mullan. Antibiotic-resistant bacteria in the Hudson River Estuary linked to wet weather sewage contamination. Journal of Water and Health, 2013