Study finds sources of creek pollution
By SEAN PATRICK NORRIS, Staff Writer
For a year, county and state officials have argued over whether animal or human waste was behind 30 years of bacterial pollution in Marley and Furnace Creeks.
Yesterday, results of a groundbreaking new study revealed the answer: It's both.
The report by researchers at Salisbury University, released by Maryland Department of the Environment, found that almost two-thirds of the bacteria in the polluted creeks comes from human and dog waste.
Wild animals were the top potential source in Furnace Creek, producing 38 percent of the bacteria in samples tested over the last year. But humans waste was close behind at 33 percent, while pets were responsible for 29 percent, according to "Identifying Sources of Fecal Pollution in Shellfish and Nontidal Waters in Maryland Watersheds, November 2007-June 2009."
The findings were similar in Marley Creek, where dogs were the leading source at 35 percent, followed by humans at 34 percent and wildlife at 31 percent.
"This is (a) densely populated suburban/urban (area) mostly served by public sewer which discharges outside of the watersheds but has lots of infrastructure potential for failure/overflow," a field researcher wrote in the report.
"There are few parks and public dog walking areas. Pet waste along the B&A Trail is abundant."
Researchers from Salisbury spent a year collecting monthly samples of Marley and Furnace creeks as well as six other county waterways contaminated by bacteria from human and animal waste.
The study is part of a court-ordered program by the Environmental Protection Agency, detailing for the first time sources of pollution in all impaired waterways. Data will used to set the total maximum daily loads for polluted creeks by September 2010, the level of pollution a creek can absorb and still meet water quality standards.
No county rivers meet the standards of the Clean Waters Act, but only Marley and Furnace creeks, along with parts of Rock Creek in Pasadena, have been permanently closed to swimming and wading by enterococci pollution, the bacteria found in all animal waste.
After a series of stories in the Maryland Gazette last summer examining the long-term pollution, state lawmakers started a committee and an investigation.
County officials maintained the pollution in Furnace and Marley is most likely the result of pet and other animal waste washed into the creek by stormwater runoff. They linked Rock Creek contamination to thousands of failing septic systems in Pasadena. Rock Creek was not included in the study.
Dr. Kathy Brohawn, who handles technical and regulatory service matters for MDE, said the ratio of bacteria from human waste is similar to what has been found in other urban areas of the state.
"We aren't exactly sure (how that bacteria is introduced)," Brohawn said. "(The area) is served by public sewer that would either mean illegal connections or failing infrastructure or sewage spills."
Wild animals for Furnace Creek included deer, fox, rabbit and raccoon while Marley Creek had beaver, deer and fox. No live stock or farm contributors were found.
"Wildlife is predominated by fox. Their abundance was surprising," a researcher wrote in the report. "There were almost no whitetail deer, something else I found surprising."
Ron Bowen, county director of utilities, was unable to comment on the report yesterday. Bowen has been a defender of the county sewer system, saying it is not a contributing factor in the pollution.
Del. Nic Kipke, R-Pasadena and chairman of the county delegation's workgroup on creek pollution, said money recently dedicated to county sewer upgrades may not be enough.
"This puts a magnifying glass on the human contribution. It's a reminder that we have an antiquated system that I believe needs more attention," Kipke said.
"It's going to take more county resources to find out what other parts of the system are failing and to upgrade the system. This should be the county's first priority."
As for the pet contribution, Kipke was optimistic that stronger enforcement of current laws regarding pet waste would help.
"One thing that I know about this area is that people respond to concerns about the bay," he said. "If the people around the creeks are made aware, with scientific evidence, of the pet population's contribution to the bacteria problem I'm sure they will take notice."
Researchers were surprised to find that sediment and sands in the creeks' watersheds were contributing to bacterial counts. Enterococci does not normally survive more than a few hours outside a body.
They could not determine how large of a factor the sediment and sands were or how the bacteria was introduced to sediment.
"We kind of came out of this with more questions than answers," Brohawn said.
Other waterways in the county showed livestock as a source of bacteria, breaking the data into four sources:
Wildlife was the main contributor of bacteria in the Magothy River with 28 percent, pets contributed 26 percent, livestock 26 percent, and humans 20 percent.
The Severn River was also led by wildlife with 28 percent, livestock 24 percent, humans with 24 percent and pets with 23 percent.
The South River was led by pets with 33 percent, livestock at 24 percent, wildlife registered at 22 percent, and humans at 21 percent.
The West Chesapeake Bay, an area between the South and Rhode rivers, also led with pets at 37 percent, humans at 28 percent, wildlife with 19 percent and livestock at 15 percent.
The Rhode River showed wildlife as the main contributor with 36 percent, livestock at 24 percent, humans at 22 percent, and pets 18 percent.
The West River showed pets as the main contributor at 37 percent, humans at 28 percent, wildlife at 19 percent and livestock at 15 percent.