For our spheres unit, we decided to find out the water quality of the Coquitlam river and the oxbow pond behind our school and compare them. One of the first things we did to compare the river to the pond was measure the temperature both in the water and the air. In order to measure the water temperature, some of my classmates put on chest waders and hold a thermometer in the water for two minutes. This was done in two different sections of the river, two different sections of the pond, once in the air around the river, and once in the air around the pond. After we had measured the temperature, we had to learn how to identify invertebrates and what they can tell us about water quality. We spent several days learning about them, and which species were sensitive to certain conditions. Once we had learned about invertebrates, we were ready to go into the water and find them.  

To find invertebrates in the river, we divided into groups and one person per group got to wear chest waders and go into the water to look for invertebrates, while everyone else waited on shore. The people in the water had to then find a spot in the water to find invertebrates. The method they used for finding invertebrates was to prop a net underwater positioned slightly behind them and then use a scrubber to scrub rocks in front of them in a 30cm by 30cm area. I was not the person in my group that went in the river, so I do not know quite exactly how hard this process was, but I think it would be quite cold as you had to scrub the rocks underwater, meaning your hands would be submerged in the river the entire time. Once the scrubbing of rocks was complete, the net (which had caught all the invertebrates that had been scrubbed of the rocks) was brought to shore and emptied into a bucket filled with water. Each group then identified the invertebrates they had found and released the invertebrates back into the river (except for a few species who couldn’t be identified, which were brought back to our class to view under the microscope). 

In order to find invertebrates in the pond we had to use a different strategy. Since the rivers bottom was made of rocks, we were able to scrub the rocks to find invertebrates, however the ponds bottom is made of mud and dirt, so there are not any rocks to scrub. Instead we had to use our nets to get scrape dirt off the side and bottom of the pond. This process felt less scientific, as instead of scrubbing rocks in a specific area, you were essentially putting small amounts of dirt in your net. but still attempting to stay in a specific area. Once this process was complete the contents of the net were put in the bucket, and you then looked for invertebrates and identified them. 

My group found several different invertebrates. We found four invertebrates, all from the river. Unfortunately, my group was unable to find any invertebrates in the pond. I believe this is because most groups searched for invertebrates in the same area, so by the time our group got there most of the invertebrates had been already found. In the river we found two mayfly larvae, one cranefly larvae, and one dragonfly nymph. Other groups found cadisfly larvae, snails, watermites, and leeches as well as more mayfly larvae. Mayfly larvae, cadisfly larvae and stonefly nymphs are all category one invertebrates, which means they are pollution sensitive and can only live in water with excellent quality. From this information we can determine that the coquitlam river must have very good water quality. 

To find the ponds water quality was more difficult for my group, since we were unable to find any invertebrates. Luckily, the rest of the class had found a variety of different invertebrates, so when the class combined all of our findings, we were still able to determine water quality. There were many invertebrates the class found, such as dragonfly nymphs, sowbugs, watermites, and alderflies. My group then found that there were no category one invertebrates, meaning that the water quality was not good enough for them to survive there. However, there were category two invertebrates, meaning that the water quality was somewhere in the middle range between excellent water quality and poor water quality. 

After this we used water samples we had collected from both the river and the pond to determine the pH of the water. Lastly, using information provided to us by the teacher and data we had collected we found the overall water quality of the coquitlam river and the oxbow pond. Our group calculated that both the oxbow pond (74.14%) and the coquitlam river (82.26%) had overall good water quality. This lines up with what the invertebrates said about the water quality, with the coquitlam river having better water quality than the oxbow pond, but them both having good water quality overall. 

I really enjoyed doing this study on water quality, as I thought it was a good balance of hands on work and learning about different aspects of water. I feel as though I have learned a lot about how important water quality is and what impacts it has on invertebrate life. I wish that we could have learned more about what impacts invertebrates have other life forms, as I find it fascinating to learn about how small things can have big impacts on the environment because of how everything is connected. I also wish that instead of the butterfly nets we used we could have had nets that were designed to go in the water, but I understand that because of school budgets this was not possible. Overall, I learned many things from this water quality study, and I look forward to doing more things like this in the future.