EPA Ambient Water Quality Criteria 1986
The article discusses how the EPA determined the use of E.coli as a water quality parameter and how the standards were set.
Distribution and Characterization of E.coli within the Dunes Creek Watershed, Indiana Dunes State Park
The article discusses the natural occurrence of E.coli in an Indiana watershed and the effects that it can have on recreational waters.
E.coli and Indiana Lakes and Streams
The link is an education/informational site from Purdue University that discuss the effects of E.coli on Indiana water bodies.
NRCS Information About Water