Adventure #6:
Clean and Safe Water
Clean drinking water is a valuable and limited resource...
Of all the water on Earth, 97% of it is salt water, and only 3% of it is fresh water. Of that 3% of freshwater, 2% of it is locked up in frozen glaciers as you learned in Adventure #3: "Water Storage". That means that only 1% of water on Earth can be used as drinking water! A lot can go wrong when it comes to the availability of safe drinking water, including droughts, pollution, and contamination.
Pollution vs Contamination: What's the Difference?
Source: Flickr, CC license
Contamination
Contamination occurs when water contains contaminants. Contaminated water is usually not harmful to drink or use, but it is not pure. Scientists, such as chemists, hydrologists, and microbiologists often study contaminated water. While contaminants are usually harmless, they might make humans or wildlife may sick over long periods of time.
For example: A man always mixes a cup of salt into his water. The water is contaminated. It does not harm him to drink this water, but over time, all of that extra salt makes him unhealthy and eventually causes him to get sick.
Source: iStock, Dmitry Berkut, CC license
Pollution
Pollution occurs when water contains a pollutant. Pollutants are often the result of waste products and chemicals. Sometimes, pollution can also occur when a contaminant reaches an alarming concentration, making the water harmful to drink or use. Pollutants are always harmful.
For example: A farmer allows his cows to spend too much time near a river that a nearby town depends on for drinking water. The water becomes polluted by the cows' waste. Not only is it really gross to drink cow waste, but it can introduce harmful bacteria and viruses into the water, which can quickly make us very sick.
Would you Rather!?
If you absolutely had to, would you prefer to drink contaminated or polluted water? Both are totally gross!!
Using the information above, write your answer in your Field Journal. Make sure to explain your choice and the reasoning behind it.
Remember, clean water is important to our health. Please be safe and avoid drinking contaminated or polluted water when possible!
Source: Envirotech Tech, CC license
Activity: Drawing Pollution
Part 1: In your Field Journal, draw an environment in which the water has been polluted and is unsafe to drink.
What do you think would happen to the plants and animals that depend on that water resource?
What is the source of pollution in your drawing?
Remember to draw like a scientist: include labels and annotate your thoughts!
Part 2: Now draw the same environment but clean it up! Remove the source of pollution and show how clean water impacts the environment around it!
Can you think of anywhere in your community where there might be a risk of pollution?
What steps have been taken to prevent pollution or what can your community do to help clean it up?
Remember to label and annotate your drawing!
How Substances Travel in Moving Water
Is it possible for chemical spills and pollutants on land to reach rivers and underground aquifers?
YES! Most contaminants and pollutants on land can easily leach into the groundwater. Groundwater flows deep underground through the rocks and eventually flows back up to the surface into rivers and lakes. This underground network of water can make it very difficult to identify the source of pollutants because it could be located hundreds of miles away!
However, substances in water are always carried downstream, in the same direction as the flow of the water. Water follows a strict set of rules dictated by physics and gravity--these rules can help scientists find the origin of pollution or contamination.
Activity: Oil Spill
Step 1
Gather your supplies with the help of a trusted adult! If you don't have adult supervision or you don't have all of the supplies, it's a good idea to skip this activity.
Step 2
Color your water with a drop of food coloring, this represents your "clean" water and will make it easier to see!
Step 3
Pour the cooking oil into your glass of colored water. Notice how the oil floats on top. Why do you think this happens?
Step 4
Stir or shake your container and examine how the water and oil interact. What do you think is happening?
Step 5
Try to clean the oil out of the water! There are many different tools that may be useful, so use what you have available and get creative! Don't be discouraged if your first idea doesn't work. Keep trying!
Great job! Now it's time to clean up your project by washing all of the supplies and returning them to their proper locations.
Cleaning It Up!
Clean water hasn't always been accessible in the United States. At one point in time, the water was so polluted that it was dangerous to drink from, fish out of, and swim in!
In response to these dangerous conditions, the government implemented the Clean Water Act, a set of laws and regulations regarding the quality of our water!
The Clean Water Act successfully restored the country's access to clean, safe water. These regulations still play a vital role in the management of water today.