Skip to Main Navigation. Each navigation link will open a list of sub navigation links.

Skip to Main Content

Apply Now to the University of Wyoming apply now
Visit Campus
Download UW Viewbook
Give to UW

Water Microbiology

Background & Introduction 

Bacteriologic testing of water is done to insure that enteric pathogens, capable of causing infectious disease in people consuming the water, are not present. Pathogens such as Shigella and Salmonella are difficult to detect because they are fragile and usually present in low numbers.  Thus, water is tested for fecal contamination by screening for indicator organisms (e.g., Escherichia coli or other coliforms).  A coliform is a facultative anaerobe that ferments lactose to produce acid and gas and is a Gram-negative, non-spore forming rod.  

During labs 22-24, we will be testing samples of "drinking water" for the presence of coliforms.  Each table will receive a water sample from a different water source, including the Laramie River, Laramie Water Treatment Plant, a mountain spring, a drinking fountain, etc.  Record the source of the water sample that your group is analyzing.  We will use three methods to screen the water samples: 

  1. P-A (Presence Absence) test 

  2. Membrane Filtration Technique

  3. Multiple Tube Fermentation Method (MTFM)

If these methods used to screen the water can detect no coliforms, than the water is considered safe to drink (potable). 

1000 E. University Ave. Laramie, WY 82071
UW Operators (307) 766-1121 | Contact Us | Download Adobe Reader

Accreditation | Virtual Tour | Emergency Preparedness | Employment at UW | Privacy Policy | Harassment & Discrimination | Accessibility Accessibility information icon