Biology students in Mrs. Ireland’s class tested samples for fecal coliforms this week in bottled water, Ten Mile Creek (located on our campus), and the Maumee River. Coliform bacteria are strains of bacteria that live in the guts of organisms – the most notable coliform bacteria is E. coli. The presence of coliforms in waterways can indicate contamination with sewage, and indicate there may be risk of disease-carrying bacteria in the water as well. The blue/purple dots on the Petri dishes represent E. coli colonies – as you can see, lots in the creek and river, but none in the drinking water! This connects to their study of ecology and assessing the health of our ecosystems, both terrestrial and aquatic.
Students will go out into the creek next week to sample benthic macroinvertebrates (bottom dwelling organisms that lack backbones and are visible with the naked eye) as a means of “biological water quality testing.” Certain benthic organisms are more tolerant of pollution than others, so by identifying organisms in each pollution index category, we can determine if the creek is healthy or polluted.