Officials said the spike was probably because of heavy rains causing runoff from land, such as pet waste, commercial farming activity and other contaminants flowing into the river and its tributaries, The Oklahoman reported.
Translation: All of the butt mud on land near the river gets washed into it by rain, causing the E. coli contamination.
In 2009, some athletes competing in a triathlon got sick after swimming in the Oklahoma River because of the bacteria.
Although the city initially said the likely culprit was cow poop, state Commissioner of Agriculture Jim Reese told KFOR-TV that the 2009 incident was likely from human feces.
“The city doesn’t dispute that there are, at times, human waste in the river,” OKC spokeswoman Kristy Yager told KFOR. “We do know that there are two trailer parks that are on the river and our concerns are they are sources for contamination in the river.”