Decatur School students are performing water tests in the classroom.

The Stephen Decatur School has been involved with studying the Poquessing Watershed for the last five years. This year, we continued our interest in the subject by concentrating on water testing and how water life is influenced by the actions of humans (mainly polluting the Poquessing Tributary across the street from our school).

On December 10, 1998, the two fifth grade classes involved in this work had the privilege to visit the ECOVAN for the second time and complete the work they started last year. While in the Van, the children had experiences with what happens to water organisms when water is polluted (Fred the Fish), the drinking water treatment process, and building a watershed model. After their activities in the Van, they were taken to the creek across the street from Decatur School where they did water testing. The children tested for temperature, Coliform bacteria, dissolved oxygen, pH, nitrates, phosphates, and turbidity using the Green Water Monitoring Kit. These groups of children have had experience with water testing last year also, but this year the materials they are using are more appropriate for independent study in small groups.

On December 22, 1998, the children did their second set of water tests. The weather prevented the children from going to the creek, so we brought the creek water to the children. The two tests that needed to be completed at the creek immediately after the water was collected was the dissolved oxygen test and measuring temperature. Two students accompanied the teacher to do these tests. Back at school in the SELab, small groups performed the other tests (Coliform bacteria, pH, nitrates, phosphates, and turbidity).

The children found that the results of these tests showed:

• Temperature: 10 degrees Celsius (organisms are less sensitive to pollutants in cooler water and the cooler the water, the more dissolved oxygen there is)
• Dissovled Oxygen: 8 ppm (a water reading below 5 ppm could not support a diversity of water life)
• Nitrates: 0
• Phosphates: 1 ppm
• Coliform Bacteria: clear
• pH: 8 ppm (most aquatic organisms can survive in water that has a pH range between 6 and 9)
• Turbidity: 0 (turbidity is a measure of how clear the water is; the higher the turbidity, the cloudier the water)
• DOBOD: clear

The children were also involved in a lesson that helped them understand that the amount of usable water for humans on the Earth is very little compared to the total amount of water found on the Earth. An experiment on the permeable and impermeable surfaces of a watershed demonstrated to the children what happens to water (rain, snow, etc.) in each of these situations and how this influences the watersheds they live in.

The children will be doing more series of tests through the winter and spring. They will be sharing the information and results with children from other schools so they may compare the quality of different watersheds.