Littered with trash and leaves, M-A’s water fountains are notoriously repulsive. Seeking to gauge the cleanliness of the school water fountains, we tested five for bacteria growth.
After thoroughly swabbing the mouthpieces of five randomly-selected water fountains, we spread each sample in a petri dish with luria broth agar, a nutrient that feeds bacterial growth. We then incubated each petri dish at 78 degrees for 72 hours, with a desk lamp as a heat source in a dark environment. While ideal growth conditions on those specific plates are 80-95 degrees, we sought to mimic regular conditions to best estimate everyday bacterial exposure.
Thousands of bacterial colonies were formed, mold grew, and after being matured for seven days, the initial five petri dishes took on an odor reminiscent of the olfactory disruption associated with gastrointestinal distress and barbecue chips.
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Petri dish from location C, downstairs G-wing water fountains between the bathrooms. 
Petri dish from location D, water refiller at end of G-wing. 
Petri dish from Location E, water fountain near I wing bathrooms. 
Petri dish from location F, water fountain near the soccer field. 
Petri dish from location G, the K-Wing water fountain.
With the exception of the K-Wing water fountain, each petri dish bacteria colony was composed of indistinguishable bacteria and another bacteria resembling Escherichia (E.) coli. According to the CDC, E. coli originates in the guts of cows, and diffuses when cow feces washes into water sources. It can also propagate through water runoff and faulty sewage systems. This makes sense however, because many of these samples are surrounded by bathrooms.
E. Coli is not harmless. It can induce bloody diarrhea, stomach cramps, and vomiting. Still, the chances of ingesting it and experiencing those symptoms are meager.
In addition to swabbing water fountains, we obtained samples from environments one would expect to be more contaminated than a water fountain—an unwashed water bottle and a human hand. We also tested two human mouths (which can contain thousands of bacteria), but found no significant growth.
In addition to possibly containing diarrhea-inducing bacteria, the bacteria formed on M-A’s water fountains is considerably more concentrated than what forms in a water bottle or mouth, which ideally should be cleaner than a water fountain. However, because the non-water bottle petri dishes grew so many fewer colonies (and frankly looked way less disgusting), it definitely means the water fountains are extremely unhygienic. A possible explanation for this could be that the water fountains are exposed to more people, and thus more bacteria, and so it becomes more contaminated in this medium.
Though it is impossible to determine the exact bacteria in the petri dishes without biochemical staining and testing, through visual observation we can verify that the water fountains at M-A contain more bacteria than a typical water bottle or mouth, signifying that they likely are as filthy as they are rumored to be.
