by:  Eric Reutebuch, President  Lake Watch
 Appeared in July 2021 issue of Lake Magazine

In the past year, Lake Watch of Lake Martin reported high levels of E. coli (fecal contamination) flushing off the watershed in streams above the lake. This presents a bacterial contamination risk to our Treasured Lake, which is something nobody wants. Lake Watch uses the Coliscan Easygel bacterial plating method, supported by Alabama Water Watch, to test for E. coli, the bacteria that indicate fecal contamination from warm-blooded animals. The test is easy, reliable and affordable (about $3 per test); however, it does not give information on the source of fecal contamination.

Enter Auburn University professor Dr. Yucheng Feng and her enterprising graduate student Wenjing Ren. I had collaborated with Dr. Feng over the past few decades before I retired from AU. She is a top-notch microbiologist in the Department of Crop, Soil and Environmental Sciences at AU and an expert in microbial source tracking. MST refers to scientific analysis of genetic material of microbes (like E. coli) that originated in the gut of a warm-blooded animal and was passed via feces into the environment, in this case a stream or our lake. 

Lake Watch contacted Dr. Feng last year, inquiring about conducting MST analyses to assist in determining the source of fecal contamination originating above the lake. Dr. Feng’s energetic grad student, Wenjing, penned a proposal, in collaboration with Lake Watch and Lake Martin HOBO, for a United States Geological Society grant to analyze fecal contamination in the Lake Martin watershed using MST. She will work in conjunction with Lake Watch volunteer monitors to collect samples from key streams above the lake and then return to Dr. Feng’s AU lab. Under Dr. Feng’s direction, Wenjing will conduct MST using polymerase chain reaction analyses. 

“Eric, quit using those big words”, you’re probably saying. And, what the heck is PCR analysis? Sorry – I can’t tell you. You’ll have to attend our Lake Watch annual meeting this October and ask the professor (details to come, see lakewatch.org for more info). What I can tell you is that PCR has revolutionized the diagnosis and monitoring of genetic disorders, the analysis of ancient DNA in archeological studies, the analysis of genetic fingerprinting in forensic science and parental testing and detection of pathogens (like, in our case, certain fecal bacteria) in nucleic acid tests for the presence of pathogens and/or diagnosis of infectious diseases. I can also tell you that these analyses of streams flowing into the Tallapoosa River above the lake will go a long way in telling us the source of the fecal contamination. PCR can distinguish whether the fecal bacteria come from human, cattle, chicken or other animal sources. This information, once obtained for each stream, will enable us to work toward resolving the contamination by working with landowners, watershed managers, local and state government and other waste management entities.

The last thing you want to think about as you take a cool dip in our Treasured Lake is fecal contamination. We think that, with the help of AU scientists, you won’t have to. Consider joining us in our ongoing efforts in watershed stewardship to keep our lake clean. Go to lakewatch.org and come aboard. 

~ Eric Reutebuch is president of Lake Watch Lake Martin