Water covers more than 70 percent of the Earth’s surface and is a vital compound for all life forms. The two hydrogen atoms that are covalently bonded to an atom of oxygen affect health, the weather, agriculture, transportation and politics. A high school science fair project that uses water can show peers and spectators how small changes can have economic and environmental health implications.
Reducing Household Water Use
For this project, a student evaluates his family’s water household water use and then implements changes to save water, hypothesizing the differences that the adjustments will make. Such changes can include placing aerators on faucets, fixing leaks, only washing full loads of laundry and using harvested rainwater for the garden. To verify if his efforts made a significant difference, the teen compares the water bills the home receives at the beginning and end of his project. He also describes simple ways that the public reduce its water consumption, citing facts about the community’s and nation’s indoor and outdoor water use.
The Components of Runoff Water
When it rains, runoff water carries debris and toxins down storm drains and into watersheds. In this project, a student collects and analyzes water runoff from different sources to determine the types of contaminants at each site. Sources can include a driveway, lawn, parking lot, local park, city street and farmland. Tests that the teen can conduct for analysis take into account pH levels, nitrogen levels to determine the presence of fertilizers, chlorine levels, dissolved oxygen, heavy metals and water hardness. The student shares information about studies conducted on the watersheds and explains how the compounds found in her water samples can affect the environment. The teen also explains ways that the public can reduce runoff water and its contamination, such as building a rain garden or using biodegradable soap to wash cars.
If a science project allows the use of live organisms, a student can use the freshwater crustaceans Daphina magna -- water fleas -- to verify water quality from several sources, including ponds, tap water, runoff water and water pooled in parking lots. The student makes a hypothesis about which source of water is the cleanest. After establishing a stable culture of water fleas and separating the crustaceans into different jar, including a control jar, the student pours the collected water samples into the jars. After 12, 24 and 48 hours, the student counts the remaining live Daphina in the jars. As time progresses, he also periodically monitors the heart rate of the water fleas under a microscope.
Chemicals in Rainwater
In this project, a student assesses the rainwater that she collects from different geographical areas and makes a hypothesis about the location of the purest rain. Such areas can include her home, inner city, the beach and rural farmlands. The teen analyzes the rainwater samples to determine acidity levels and other chemical levels using a water testing kit. She also uses the collected rainwater to germinate quick-growing seeds such as radishes or alfalfa to see which seeds grow first or the fastest.