Water Tests Show High Levels of Harmful Bacteria in Some Fresh Water Streams and Lakes in Frederick, Howard, and Harford Counties

(ANNAPOLIS, MD)—Some fresh water streams used for swimming, fishing, and other recreation in Maryland have high levels of potentially harmful bacteria, especially after rainstorms, according to water samples taken to date through the summer. Some tests showed bacteria readings as much as 200 times above safety standards set by the U.S. Environmental Protection Agency (EPA).

The water testing was conducted through a partnership between the Chesapeake Bay Foundation (CBF), Hood College, Howard Community College, and Harford Community College.

"It would be great if we could make all our streams 'kid-safe' so that they can be explored on a hot summer's day. I hope that our monitoring will be a first step in identifying water quality issues in public places," said Dr. Drew Ferrier, Director of the Coastal Studies Program at Hood College. "Exploring streams, wading in cool waters, finding crayfish and frogs—these are summer past-times. Kids are attracted to streams in public places whether or not they are being used for swimming."

The samples were taken in Frederick, Howard and Harford counties, and tested in biology laboratories of the three partner colleges. The sampling and testing will continue the remainder of the summer. Results can be found by clicking here.

Samples were taken in a variety of fresh water streams in Frederick and Harford counties, and predominantly in lakes in Columbia in Howard County. Some streams are used as swimming holes, others for fishing or boating. Some are used less for recreation, but flow through public parks or city or suburban neighborhoods.

Findings to date include:

  • Kilgore Falls, one of the most popular swimming holes in Harford County, had bacteria readings nearly 50 times higher than safety limits even 48 hours after a heavy downpour. The pool at Kilgore was featured in the Disney movie, Tuck Everlasting.
  • Unhealthy readings occurred in most Frederick County streams even during dry weather. Readings often jumped to much more unhealthy levels after storms. For instance, Glade Run that flows through the small town of Walkersville, had bacteria readings in dry weather more than 60 times higher than levels the EPA considers safe for all types of recreational contact with the water, including frequent swimming. Those levels spiked to levels more than 200 times the safety limits after rain storms of at least one-half inch of rain.
  • Lakes in Columbia generally were well within safety limits in dry weather tests, but after storms were about three times above levels the EPA considers safe for all types of recreational contact with the water, including frequent swimming.

CBF and the partner colleges undertook the project because streams and lakes in the area often aren't tested by public authorities. Federal law requires sampling and testing at public beaches, few of which have been identified as such in fresh water areas in Maryland. This project attempted to target recreational areas of various sorts. For instance, many sites in Harford are known to be swimming holes or popular kayaking locations.

"We wanted to see if fresh water streams and lakes in counties further away from the Chesapeake Bay are experiencing the same kinds of pollution problems as the Bay itself, especially polluted runoff. These preliminary results suggest they are. That's not surprising," said Alison Prost, Maryland Executive Director of CBF.

In Frederick and Howard, samples were taken in a mix of dry and wet conditions. In Harford, weekly tests were conducted, some of which occurred with 48 hours of a rainstorm.

Water was tested for the presence of enterococcus bacteria. The EPA considers the presence of this type of bacteria in fresh water a potential indicator of other disease-causing bacteria found in fecal matter. These unhealthy bacteria can cause intestinal problems such as diarrhea when ingested. Fecal bacteria in water comes from human or animal waste. It also often suggests the presence of other pollutants such as nutrients which also are found in waste.

Some of the streams tested in the three counties this summer originate in farm areas, some in more urban or suburban areas.

Polluted runoff carries pet and livestock waste, leaking septic discharges, and other pollution off the landscape and into nearby rivers and creeks. It is known to be the major source of water pollution in many streams and rivers. The Maryland Department of Environment cautions swimmers not to come into contact with natural water for 48 hours after a significant storm, because of polluted runoff.

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