Hands-on Activity: Where Does All the Water Go?
Educational Standards :
Pre-Req Knowledge (Return to Contents)
Basic number operation skills
Learning Objectives (Return to Contents)
After this activity, students should be able to:
Materials List (Return to Contents)
Each group will need:
Introduction/Motivation (Return to Contents)
The sun causes water to evaporate into the atmosphere, and then once water vapor condenses to form clouds, water can return the surface of the Earth in the form of rain. What happens when it rains? Where does the water go? (Accept student answers.) It either runs over the surface of the earth to a body of surface water — such as a lake, river or stream — or it filtrates down through the ground. Gravitational force is the driving force behind water's movement into the ground. Once in the ground, it becomes groundwater. Groundwater flows very slowly through the dirt or soil under the ground to a space called an aquifer.
(Draw the following figure on the white/chalk board.)
What is soil? Can you think of different types of soil? How would these types of soil affect the water's ability to flow through the soil? (Answer: Soil with larger pore spaces allows greater water flow. For example, water flows through rocks or large pebbles faster than through sand.) We call the spaces between the individual particles of soil, pores or porosity and the ability for the water to flow through the soil as permeability.
Environmental engineers have developed methods to treat the water in aquifers so that it can be used as a source for drinking water. However, sometimes toxic chemicals that are dumped into the ground seep into our aquifers and make the water harmful to use. Environmental engineers not only figure out how to treat the water for these hazardous chemicals, but they also use groundwater modeling to determine where the chemicals came from and how fast they are moving through the soil. When they model the groundwater flow, they need to figure out the porosity and permeability of the soil, the direction of flow and the velocity of the chemicals. They need to look at these measurements in the areas surrounding a chemical spill, because chemicals spread out in all directions. This is called a chemical plume. Today, we are going to look at a groundwater model and investigate different types of soil. We will also calculate the velocity of a harmful chemical to see how fast it flows through the different soils.
Vocabulary/Definitions (Return to Contents)
Procedure (Return to Contents)
Before the Activity
With the Students
Attachments (Return to Contents)
Troubleshooting Tips (Return to Contents)
There are many different ways to create a tank to simulate groundwater flow. It can be done using a fish tank and creating siphons with ½" plastic tubes on either end. Search the internet for ideas. A few states, such as Wisconsin, have a website listing places from which you can borrow a tank. In addition, if there is a university in your area, it is likely that a tank exists that can be used to model groundwater; begin with the environmental engineering department.
Assessment (Return to Contents)
Discussion Question: Solicit, integrate and summarize student responses.
Brainstorm: In small groups, have students engage in open discussion. Remind students that in brainstorming, no idea or suggestion is "silly." All ideas should be respectfully heard. Encourage wild ideas and discourage criticism of ideas. Write down all of their ideas on the board. Do not provide the answer. Group their answers together as much as you can. For example, ideas having to do with: water, people or animals. Ask students:
Activity Embedded Assessment
Posters and/or Presentations: Have students make a poster of the groundwater demo labeling and defining the new vocabulary. (If time allows have students present their poster to the class.)
Question and Answer: Ask students the following questions. Have the students write their answers down on a piece of paper first, but stress the answer will not be graded. After everyone has had a chance to write an answer down, call on a student to answer the question. Did everyone get the same answer?
Problem Solving: Present the class with the following problems and ask the students to calculate which case has the greatest velocity. (Answer: Case B) Which soil had the largest permeability? (Answer: Case B)
Activity Extensions (Return to Contents)
Have students build their own groundwater module.
Activity Scaling (Return to Contents)
For 6th grade, use less technical vocabulary for younger grades.
For 7th and 8th grades, do activity as is.
References (Return to Contents)
enVISION Environmental Education, manufacturer of Environmental Education Products and Groundwater Models: http://www.envisionenviroed.net/
Google search on available ground model education resources: http://www.google.com/
Copyright© 2005 by Regents of the University of Colorado.
Supporting Program (Return to Contents)Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder
Acknowledgements (Return to Contents)
The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.