Requirement 4 (A)
Requirement
Identify where your community sources water and how it is treated and disposed. Obtain and review a water quality report from your area.
Water Pollution
Water is essential to all life on Earth, and the way it moves through the environment—the hydrologic cycle—connects every part of our ecosystems. Rainfall, rivers, lakes, groundwater, and oceans are all linked through evaporation, condensation, and precipitation, ensuring that water is continuously recycled. However, human activities and natural events can introduce pollutants into this cycle, affecting water quality for people, wildlife, and plants.
The Hydrologic Cycle: How Water Travels Around the Earth
Did You Know:
Every drop of rain that falls in a watershed eventually drains into the same river, lake, or aquifer, so pollution anywhere upstream can affect the entire ecosystem downstream, which might be many miles away.
Pollutants
Pollutants are substances that can harm the environment, including both natural ecosystems and human health. They come from many sources, such as fertilizers, pesticides, toxic metals, household products, petroleum products, and even changes in water temperature, known as thermal pollution. Understanding the sources and pathways of water pollution is the first step in protecting this vital resource.
Fertilizers
Pollutants such as fertilizers and pesticides that enter our water system from runoff are called “nonpoint source pollution” because the sources of the pollution cannot be traced to a single identifiable point.
The phosphates in fertilizers are plant nutrients that crops need, but if they get into ponds and lakes, they cause overgrowths, or “blooms,” of algae. The algae can cover the water surface, blocking life-supporting sunlight and killing some forms of pond life. When the algae die and decay, the decay process takes oxygen from the water, which in turn may kill fish and other organisms.
Pesticides
Chemicals that farmers, homeowners, and others use to control pests, such as insects, are called pesticides. Some pesticides kill only particular species, but others are toxic to many living things. Many of these toxic chemicals end up in the air, surface water, and groundwater. Pesticides in rainwater runoff kill millions of fish each year. Traces of pesticides can be found in nearly all of the freshwater fish in the United States.
Toxic Metals and Industrial Pollutants
Mercury, lead, and other toxic metals that are mined or used in industry have contaminated bodies of water. Many states have issued health warnings because of the toxic metal content of native fish. These toxic metals, as well as PCBs (synthetic chlorine compounds once used in paints, adhesives, lubricants, and electrical equipment), are also examples of waterborne pollutants that become more concentrated as they move up the food chain.
This biomagnification up the food chain impacts the environment. For instance, the number of eagles severely declined in the lower 48 states. They have recovered following decades of conservation efforts and are again common.
Household Products
Some chemicals used in household products also cause water pollution. When you clean the bathtub, for instance, the cleaning solution goes down the drain. What happens to the water then? If you live in a city or suburban area, that wastewater is piped to a water-treatment plant, where it is filtered and treated so that the pollutants can be removed and the water reused. In rural areas, wastewater may be piped into a septic tank. Eventually, water leaves the septic tank and filters down into the soil and back into the groundwater. When this wastewater contains more toxic chemicals than the soil can absorb, the chemicals also enter the groundwater.
Petroleum Products
Petroleum (oil), gasoline, kerosene, and other petroleum products are a major source of water pollution. You probably have heard about oil spills at sea. Oil can devastate ocean ecosystems. It kills some organisms immediately. Others die more slowly as oil coats their feathers, fur, or skin. Some oil sinks to the ocean floor, where it kills bottom-living creatures. Even with expensive cleanup efforts, it takes three to 10 years for marine life to recover from the effects of an oil spill.
Thermal Pollution
Thermal water pollution occurs when water is taken from a river to cool a power plant. When the heated water is released back into the river, it raises the river’s temperature. Just like you, fish and other aquatic organisms have temperatures they like. Thermal pollution of the water harms many aquatic organisms. It may hurt them directly or lower the amount of dissolved oxygen in water and make organisms more prone to the effects of damaging chemicals and attacks by parasites or disease.
Water Treatment
Learn where the water you use every day comes from, how it’s cleaned and delivered to your home, and what happens to it after you use it.
How Do Water Treatment Plants Work?
Wastewater Treatment Explained
Water Quality Reports
Water quality reports are annual summaries that explain where drinking water comes from, what it contains, and whether it meets national safety standards set to protect public health.
Resources
Resources
The CDC explains Consumer Confidence Reports (CCRs), the annual water quality reports from local public water systems, and explains how to find and understand your area’s report.
Suggested Activity: “Life of a Drop of Water” Poster or Digital Slide
Suggested Activity: “Life of a Drop of Water” Poster or Digital Slide
Prepare for a discussion with your counselor by creating a poster or digital slide showing the “life of a drop of water” where you live, including treatment and disposal.
You might include some of the following information:
- Source: Add the water source for your community. Lake, river, etc.
- Treatment: Show the key treatment steps, such as filtration, disinfection, and chemical adjustments.
- Distribution: Illustrate how water is delivered to homes and businesses.
- Use: Include examples of how water is used in daily life.
- Wastewater: Show what happens after water is used.
Add one or two things you learned from your water quality report.
Ask a few people to review your poster or slide to ensure it is visually engaging and easy to follow.
Now that you have learned how your own community disposes and treats your drinking water,
let’s investigate local and regional areas that experience periodic flooding and/or drought.
