How Do We Track Polluted Water?

Scientists track pollution from a number of sources by looking for indicators.

Water is perhaps the world's most vital natural resource, with all life depending on it to live. Yet water is highly susceptible to contamination from modern-day human activities, with pollution coming from sources like factories and other sources like the atmosphere. In 1972, the Clean Water Act established America's commitment to tracking and controlling polluted waters. Tracking polluted water is often done by tracking a contamination indicator in the water.

Instructions

1. Study the groundwater. Septic systems and other sources of pollution can contaminate the groundwater, allowing researches to track and study the flow of pollution. Stanford University researchers tracked a plume of polluted groundwater from a septic system to the coast, giving scientists improved wastewater management in coastal communities. Tracking groundwater can help raise awareness about groundwater contamination and encourage communities to implement conservation efforts.

2. Look for fish kills. When large numbers of fish die at one time, the event is called a "fish kill" and can help scientists to track the source of the water pollution. Using the path of dead fish as a clue, researchers then determine where the source of pollution is coming from and how to best stop it from continuing. A fish kill also sometimes happens due to natural causes, but often pollution is the cause that scientist find after tracking the kill.

3. Evaluate microbiological contamination. Microbiological fecal contamination of surface water such as lakes and rivers can come from many sources, including human sewage, livestock manure, wildlife and urban runoff. By identifying and targeting the source of this pollution, action can be taken to mitigate the risk that contamination can bring. Regular testing of surface water helps scientists to know what is a normal level and what is a level that needs to be studied further.

4. Test for identifying markers. Artificial sweeteners pass through the human body virtually unchanged, ending up in wastewater and becoming widespread in certain environments. Scientists use artificial sweeteners as an identifying marker to track pollution from domestic wastewater, determining how much urban pollution is escaping into the environment.

Tips & Warnings

• When studying data, make sure your research is from a reputable source.

• Collect as many years of data as possible for best results.

• Consult a local scientist if you have any questions.

References

• Environmental Protection Agency: Polluted Runoff
• EurekAlert: Stanford scientists track polluted groundwater to the sea
• Iowa Department of Natural Resources: Lacona Fish Kill Update
• Journal of Water and Health: Evaluation of microbial source tracking methods using mixed fecal source in aqueous test samples
• Discovery Channel: Sweeteners Linger in Groundwater

Resources

• Environmental Protection Agency