Water Quality Experiment
I am constantly on the lookout for ways to take science out of that dry text book and to make it more applicable to a student’s daily life. Experiments are great ways to get kids interested in science. Partnering that with a popular current event or something that could affect a student’s life right now makes science come alive. This water quality testing experiment makes science relevant and shows why water quality is important to us all.
Water quality is currently a hot button issue in communities across the country. Harmful bacteria and high levels of chemicals and other substances that cause health problems in humans have been found in the public water supply of communities like Flint, Michigan. Since our bodies cannot live without water and our way of life revolves around the use of water from our hygiene practices to the manufacture of goods, water quality is a huge concern.
Water Quality Confidence
Citizens generally trust that water is safe. Most rely on public supplies controlled by water companies. Others get their water from ground water sources, such as wells, that are not monitored. How do we know for sure that this water is safe to drink?
The EPA now requires water supply companies to produce Consumer Confidence Reports to their customers to show their water is safe. You can get this report from your local water company or from the EPA’s website. These are yearly reports and represent the average testing data for that year. Well water from private land is not monitored.
Some people want to ensure the quality of their water, so they install water softeners and/or water filtration systems in their homes. These are designed to remove unwanted minerals, chemicals, and bacteria from the water. But, how do we know that these are doing their jobs?
Water Quality Testing At Home
If you are at all concerned about the quality of your home water supply, you can do water quality testing at home easily and inexpensively. We used Test Assure kits, but now they are currently not available.
However, Varify has created water quality test kits that test for a variety of substances.
Related post: Testing The Properties Of Water
Water Quality Experiment
Water testing is a great experiment for students to show how science is involved in their daily lives. Comparing several water sources can lead into discussions and even further studies into the differences of those sources.
We tested for:
- Alkalinity
- Hardness
- pH
- Iron
- Chlorine
- Nitrate nitrogen
- Nitrite nitrogen
- Copper
- Total dissolved solids
Choosing Water Sources
First, we determined the water sources we wanted to test. Since we have a water filtration system, we wanted to test our tap water before and after the filter. We were curious to see if the filter was really making a difference. Then, we decided to test those samples against a sample of purified bottled water.
Water Testing
The water testing was super easy. The kit used strips that were dipped in the water samples. Levels were determined by the color of each testing area on the strip in comparison to the included chart. This makes the testing safe and easy for all ages.
The total dissolved solids (TDS) level was determined by using the enclosed TDS monitor. Just swish it around the water sample until the reading levels out.
Results
In our samples, we found that our municipal water source had very low levels of chlorine, iron, nitrates and nitrites. That same water source did have copper level at the upper level that the testing kit monitored. When we tested the water source from the water filter, we found that the water filter removed much of the copper.
When it came to hardness, alkalinity, TDS, and pH, there was no difference in the tap water and filtered water. Both samples contained fairly high levels of hardness, a pH of 7, and a TDS level of around 420.
The purified bottled water had some differences. While it had the same low levels of iron, nitrates, and nitrites as the other two samples, the bottled water contained a bit more chlorine than the other samples. The bottled water also had a TDS of 001, a hardness level of 0, and a pH of 6. These were much different than the other samples.
Related Post: Charcoal Water Purifying Experiment
What Do Water Testing Results Mean?
Water quality testing results give you a picture of the levels of substances in a sample of water at a given time. These levels can be indicators of problems in your water source or problems in your plumbing system (due to leaching minerals from pipes and deposits). An alarming test result might prompt you to call your local water supplier or to look into ways to improve your well water by adding a filtration system or water softener.
Comparing results from samples can help you make informed decisions about your water supply. You can determine if your water filter or softener is working. It may prompt you to start drinking bottled water. It may show you that your tap water is just as safe as bottle water.
When doing a water quality experiment with students, let them determine what the results mean and what, if any, actions should be taken based on their findings.
More Water Testing Experiment Ideas
When testing water quality, you might want to think beyond your typical water sources. Test water samples from your swimming pool, a pond, a creek, or collected rainwater. You might even test several different bottled waters. Find the difference between the bottles labeled “spring water” and those labeled “purified”.
Use this interactive map from the US Geological Survey to find groundwater sources near your home.
Order your water quality testing kit and then let me know if the result surprised you and what actions you took because of it.
I hold a master’s degree in child development and early education and am working on a post-baccalaureate in biology. I spent 15 years working for a biotechnology company developing IT systems in DNA testing laboratories across the US. I taught K4 in a private school, homeschooled my children, and have taught on the mission field in southern Asia. For 4 years, I served on our state’s FIRST Lego League tournament Board and served as the Judging Director. I own thehomeschoolscientist and also write a regular science column for Homeschooling Today Magazine. You’ll also find my writings on the CTCMath blog. Through this site, I have authored over 50 math and science resources.