An Introduction to Water Quality
Water is a limited and precious resource on our planet. No living thing – plant, animal or human – can survive without a clean supply. Project WET’s “Drop in the Bucket” activity is an excellent way to illustrate the relative scarcity of fresh water on Earth. View the “Drop in the Bucket” lesson plan online, or contact the Clark Fork Watershed Education Program to request a hard copy.
As we have seen, in its pure phases, water demonstrates unique physical and chemical properties. But pure water, that is, just H2O, is rarely if ever found in nature aside from lessons or laboratories. For example, even pure or deionized water that is allowed to sit out in a room will dissolve CO2 and H2O from the surrounding air, forming carbonic acid. That is why it is important to learn and understand more about the water in our environment.
Many human and environmental/natural impacts and phenomena change the properties of pure water. These changes, big or small, result in a never-ending variety of solutions and mixtures. Our groundwater, rivers, lakes and oceans are common examples and are often significantly different in their characteristics when compared to pure H2O.
Let’s explore water in our environment, how it changes and how we can make inferences about its quality through the measurement of basic parameters.