The Pastoral Image of Cows Drinking from a Stream Has a Hidden Story.
Pennsylvania has long been home to a robust agriculture industry, where cows, hay bales, and horse-drawn plows dot rolling hills of grasses and grain. For those acquainted with these scenic landscapes and the hard-working farmers who maintain them, the pastoral image of lazy dairy cows drinking from a trickling stream is a familiar one. To the untrained eye, it seems a natural ornament of bygone days.
What Hides in Murky Waters
Did you know that when cows and other livestock are free to roam in streams, they trample the streambed and disturb the fragile ecosystem that supports freshwater fish, bugs, and other critters? They also leave behind waste containing microorganisms like E. coli, Cryptosporidium, and Enterococcus that can contaminate the stream and pose a public health risk.
Water treatment facilities can effectively deactivate these contaminates, thus purifying the water flowing from the taps in our homes. But recreational users and animals are at risk of contracting disease simply through contact with — through swimming, boating — and drinking the stream water.
There are other threats to clean streams, such as human waste from leaking septic tanks and the loss of streamside forests cut to make way for other land uses.
Fortunately, water treatment facilities have procedures in place to make water safe for drinking. But of course, the dirtier the water, the greater the cost to treat it.
What the Researchers Found
Surface waters like streams and rivers have tremendous value not only because they provide 170 million people in the United States with drinking water, but also because they are beautiful and richly diverse ecosystems to be enjoyed through fishing, swimming and boating — activities that could be unsafe in contaminated waters. A key part of protecting freshwater resources is identifying and reducing sources of pollution.
Microbiologist Jinjun Kan, Ph.D., of Stroud Water Research Center is doing just that. This summer he led a study investigating the presence of bacteria and other pathogens at 46 sites across the headwaters of the White Clay Creek, Red Clay Creek, Brandywine Creek, and Schuylkill River sub-watersheds of the Delaware River.
The research team — Villanova University student Kathleen Fisher, Stroud Center technicians Dave Montgomery and Laura Borecki, and Shane Morgan of White Clay Creek Wild and Scenic Rivers — found levels of bacteria from both cow and human waste were higher in these area streams than permitted under the recreational water quality standards of the U.S. Environmental Protection Agency.
The team also found that some of the highest concentrations of E. coli and Enterococcus were in streams surrounded by farm fields with animals. In some cases, the animals had direct stream access.
“Obviously, livestock, wildlife, and land uses play a big role in how clean our streams are. By identifying sites of contamination and using DNA tools to trace bacteria to their sources, we can help landowners make small changes that can have a big impact on water quality,” says Kan.
One such change is simply to fence animals out of streams.
Among the many best management practices landowners can adopt, fencing out animals and planting trees along the banks of streams are especially effective. Trees stabilize stream banks and prevent erosion. They act as a protective barrier between streams and upland activities that contribute to pollution.
Trees also shed leaves and branches that keep streams healthy by providing habitat and food for aquatic organisms. The list goes on. See the article “Trees Save Streams” in the March 2016 issue of County Lines Magazine to learn more.
Knowledge Is Power
“Not everyone knows where their water comes from,” says Matt Ehrhart, director of watershed restoration at the Stroud Center. “We simply turn on the tap, and out comes clean water. But there’s a journey that our water takes before it reaches our homes. When people know where their water comes from and about the threats to water quality, they can take charge and make positive changes.”
How Can You Help? Become a Citizen Scientist
Anyone in the Delaware River Watershed can learn firsthand about their freshwater resources and how to protect them by becoming citizen scientists. The Wiliam Penn Foundation is supporting more than 50 leading nonprofits in their efforts to reduce threats to water quality, and Stroud Water Research Center is helping these organizations grow their network of citizen scientists. Volunteers learn how to collect, analyze, and interpret water-quality data, and they learn what questions they should be asking and why.
If you’re interested in becoming a citizen scientist, contact David Bressler at Stroud Water Center. Penn State’s Master Watershed Steward Program, offered in extension offices in area counties, also trains volunteers in watershed management through a free program. For information, contact Erin Frederick at 610-391-9840.