How Ground Water Flows

The groundwater flow models are used to demonstrate ground water movement principles. Constructed with clear plexiglass, the model allows viewers to watch how the water within a groundwater system travels. For example, the movement of water towards a pumping well can be easily observed.

Ground water is one of our major natural resources. In Nebraska, between 80 and 85 percent of the population uses ground water as a drinking water supply. Ground water is used for irrigation on approximately 7,000,000 acres of Nebraska land. Ground water is also used by livestock, industry and in a multitude of other ways. In many places, ground water discharges to the surface and serves as the base flow for streams. Ground water's importance results, in part, from its widespread availability and use. Although Nebraska has a major ground water supply, there are areas within the state where large withdrawals for irrigation have resulted in water level declines. As a result of an increasing number of water quality problems, there is a growing concern about protecting the quality of our ground water supplies, along with conserving our available supply.

Ground Water Concepts

The model simulates an aquifer and is not an actual representation. The model and sand found within are of a much different scale to each other than what is found in an actual aquifer.

Several physical and chemical ground water concepts can be demonstrated with the ground water model. The accompanying manual describes 28 concepts that can be shown on the model. The following a a few of those concepts:

• Ground water aquifers vary in size, ability to produce water, depth, rock material, water quality, and other characteristics.
• Ground water is related to atmospheric and surface water through the hydrologic cycle.
• Artesian (naturally flowing) wells are the result of aquifers under pressure.
• The types of material (sand, gravel, clay, rock) in an aquifer affect the rate of flow of ground water. (Water flows through gravel much easier than through fine sand.)
• Human activities at or near the land's surface can contaminate ground water.
• Ground water is recharged by precipitation.

Uses of the Model

The model can be used in many different settings. It is especially effective with youth in school classrooms, for children's festivals, and with Boy and Girl Scout and 4-H groups. Also, the model can attract significant attention when used in conjunction with water educational displays. It can be useful in presenting basic septic system/ground water information to adult audiences in various types of meeting and workshop formats. Because of the model's size, it must be used with relatively small groups.

The models are constructed by the Biological Systems Engineering Research Development Shop at the University of Nebraska-Lincoln, adapted from an original design by the University of Wisconsin-Stevens Point. It takes 3 to 4 weeks from the time the order is received for the model to be built. The model is 24 inches long, 12 inches tall, and approximately 2 inches wide. The weight of the model with case is about 40 pounds.

In Nebraska, many Extension County Offices and Natural Resource Districts (NRD) have purchased the models. Extension and NRD staff are often available to provide demonstrations using the model. In some cases, the models may be available for loan. Contact your local Extension or NRD office to determine the availability of a model in your area.