Pathogenic Microorganisms in Water

Melissa Lenczewski
Northern Illinois University
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This activity introduces students to sampling and testing for microorganisms in different water sources. It also tests iodine tablets to kill coliform bacteria which interest many students. The activity utilizes prepared kits to keep preparation easy.

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This can be used from junior high school activity to graduate level classes. It can be done in everything from an introductory environmental science class to hydrogeology to geomicrobiology.

Skills and concepts that students must have mastered

Can be combined with field sampling of water samples.

How the activity is situated in the course

This can be a stand-alone exercise or combined with geochemical water sampling.


Content/concepts goals for this activity

- Methods for groundwater sampling
- Water quality evaluation

Higher order thinking skills goals for this activity

- Analysis of data
- Evaluation of water quality

Other skills goals for this activity

- Lab and field sampling
- Group project

Description of the activity/assignment

Pathogenic Microorganisms in Water: Traditionally, groundwater has been used without treatment because the soil acts as a filter, removing pathogenic microorganisms. Some potential sources of pathogens (or disease causing organisms) in groundwater include septic tanks, leaking sewer lines, sewage sludge, intentional groundwater recharge with sewage, irrigation with sewage, direct injection of sewage, domestic solid waste disposal (landfills) and sewage oxidation ponds. The objective of the session is to introduce hydrogeologist to the types of microorganisms, sources of pathogens, and a simple exercise that can be incorporated into a hydrogeology class.

Determining whether students have met the goals

Included in the activity is a set of questions

More information about assessment tools and techniques.

Teaching materials and tips

Other Materials

Supporting references/URLs


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