Water Quality Assessment

Concepts to Be Covered

• The interrelationships that exist between the physical, chemical, and biological factors inherent in any aquatic ecosystem
• Evaluation of water quality through the investigation of the physical, chemical, and biological parameters of two flowing bodies of water
• Comparison of stream's quality when flowing through a forested ecosystem as compared to one coursing through an area with human impact

Goals for the Lesson

• Complete chemical testing on site
• Determine the volume of water flowing in the stream
• Collect and identify biological indicators from the stream
• Evaluate the quality of the streams using the chemical, physical, and biological data collected
• Write a position paper explaining the stream's quality using the data collected
• Cite any differences that exist between the two streams
• Explain the impact of humans on the quality of streams

Materials Needed

• chemical testing kits
  • dissolved oxygen
  • carbon dioxide
  • nitrates
  • phosphates
  • E. coli
  • pH
  • suspended solid
• thermometer
• string
• meter stick
• kick net
• collection jars
• organism identification books
• micro/stereoscopes

Methods

1. Many times it's not obvious to students (or they just never considered it) that human development can have such a dramatic impact on the quality of a stream. In this activity, the students should be able to discern differences between a stream that runs through a natural, forested site and one that is heavily influence by human interference. The forest's ability to absorb water, recycle elements, and reduce sedimentation in comparison to developed areas should develop an awareness in the students of the value of natural, forested areas.
2. The first and second day of this activity should be spent introducing the chemical factors to be tested. The sources and impact of each parameter would be presented. Additionally, some students would be assigned a test to complete and they would become experts running that particular test
3. Other students would be assigned a physical test in order to compute the volume of the stream. (Width, depth and velocity)
4. Some students would be given the task of being "streamwalkers" and be responsible for walking upstream to observe the type of bottom, condition of stream banks, flora present, upstream development, evidence of pollution, general land use, and human impact.
5. Finally, two students would use the kick net to collect the macroinvertebrates located in the bottom strata.
6. The third and fourth day would be in the field where the students would collect their data. (The first day in the forested area and the second day in the human-influenced area.)
7. Back in the classroom on the fifth day, the students would identify the macroinvertebrates and microorganisms.
8. Concluding the fifth day, the students would research the organisms present to determine whether these organisms are indicative of good, intermediate, or poor quality water.

Evaluation

• Evaluation of this lesson could be a paper written by the students defining the quality of water in each of the streams and the determination of any effects the forested area or human-influence area had on the water's cleanliness, usefulness, of aesthetic values.
• The paper should include graphs representing the data collected.
• The paper should include a theme statement defining their findings, and it should be proven by applying the background information presented and researched.

Author

Barbara Neuburger, General McKlain High School