Water Quality Testing
Calgary Science School The students from the Calgary Science School tested water from the Elbow River, part of the Bow River watershed. Watch their video as they explain how to go about testing the quality of water. ___________________ Dr. W. H Cushing Workplace School and National Sports School The Grade 11 students from the National Sports School and the Grade 3 students from W.H. Cushing Workplace School teamed up
on one of Calgary's coldest days (-32 degrees Celcius) to meet at the banks of the Bow River in downtown Calgary to test the quality of the water.
Bow River looking east Measuring Dissolved Oxygen The students measured the amont of molecular oxygen dissolved in the water.
The amount of dissolved oxygen the water will hold (under specific conditions) is called the solubility of dissolved oxygen. We learned that there are several factors affecting the solubility of dissolved oxygen include water temperature, atmospheric pressure, and salinity. We also learned that cold water can dissolve more oxygen than warm water. Measuring pH pH measures the acid content of water. The pH scale (measured from 0.0 – 14.0 pH units) is a logarithmic scale of the hydrogen ion concentration. Solutions with a pH greater than 7.0 are classified as basic and ones with a pH less than 7.0 as acidic.
We learned that pH affects most chemical and biological processes in water. pH has a strong influence on what can live in the water; aquatic organisms have certain pH ranges they prefer or require.
|
Nitrate Testing We learned that scientists often call nitrogen a “limiting nutrient” because in low amounts, plants use up all the available nitrogen in the water and cannot grow or reproduce anymore. So, it “limits” the amount of plants in the water. Many plants that use nitrogen are microscopic algae, or phytoplankton. Additional amounts of nitrogen added to the water may allow the plants to grow and reproduce more.
We learned that the nitrate form of nitrogen found in natural waters, like the Bow River, comes from rain, snow, fog or can be deposited by wind, from groundwater, and from surface and below surface run-off that flows off and through surrounding land and soils.
Working together we learned not only how to test water, but also the importance of recording our data.
We also learned that we could study our results to determine the quality of the Bow River on this very cold day. Fortunately Eau Claire market was open so we were able to take our samples inside for further study.
|
