Groundwater System
When you think about groundwater, imagine a sponge saturated with water. The structure of the sponge consists of a network of matter. In the sponge, empty space composes the majority of the object. When the sponge becomes soaked with water, the water fills the empty spaces. Groundwater is similar to the water that fills the sponge. Like the sponge, rocks are filled with empty spaces called pore spaces that have the ability to fill with water. You will investigate the entire groundwater system in the interactivity. Click the player button to begin.
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Environmental Problems
As demands on groundwater are increasing, contamination and overuse are threatening supplies in certain areas. Groundwater is easily contaminated. When pollutants leech into an aquifer, the aquifer will require treatment before it is consumed. Major sources of groundwater pollution include sewage, farm waste, insecticides, pesticides, and road salts. Once an aquifer becomes polluted, the water in the source can either be treated or abandoned. In some cases, the water source is completed pumped dry and allowed to replenish naturally.
Groundwater may seem like an endless renewable resource; however, supplies of groundwater are limited. Groundwater replenishes naturally based on the hydrologic cycle. If the water is extracted before it is allowed to fully replenish, it becomes depleted. When groundwater is extracted from Earth, the aquifer will become more compact. The pore spaces in the aquifer will become smaller. Over time, the ground will appear to sink as more water is extracted from the aquifer. The image shown to the right is located in the San Joaquin Valley of California. You can see that in a period of around fifty years the land has sunken drastically. This occurred as water from the aquifer was used in farm irrigation.
Groundwater Features
Groundwater flows quietly underground and often goes unnoticed. Groundwater can create unique and spectacular geologic formations when it is exposed at the surface. These features include springs, hot springs, artesian wells, and geysers. View this interactivity to learn more about the features that are caused when groundwater flows or erupts out of Earth’s surface. Click the player button to begin.
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Groundwater Review
Now that you have explored groundwater, review your knowledge. In this non-graded activity, read each question and select the appropriate response. Click the player button to get started.