Written by SOLVE Jesuit Volunteer Corps Northwest members Nicole Poletto and Lauren McKenna. Photos by SOLVE Outreach Coordinator Morgan Parks.
Gladstone HS @ Eagle Creek (Eagle Fern Park in Estacada) on 2.5.13
One beautiful, rain-free morning Gladstone students hopped on the bus with one question on their mind (other than “are we there yet?”). Gladstone students were curious about the health of their adopted stream, Rinearson creek. With their morning classes excused, the world was their oyster, and the bus continued to drive, drive, drive until they reached Estacada. In comparison to Rinearson, Eagle creek is a relatively undisturbed and healthy riparian zone. After testing the water quality and surveying the macroinvertebrates at both creeks, they will be able to compare the health of the two streams!
To start the morning off we discussed conditions, both natural and human activities that could affect water quality. Since we are always in a watershed no matter where we are, what we do on land affects the quality of our water!! We learned about all of the different parameters that can be used to test water quality to assess their health such as temperature, dissolved oxygen, pH, turbidity, phosphorous, nitrogen, and benthic macroinvertebrates. Once we understood how they were interrelated, a team of students each assessed the potential water quality of a stream based on a description of it.
But wait, testing the water quality of the stream only at this one point in time doesn’t tell us that much about the health of the stream as a whole. It is a mere snapshot of stream health. That’s why we pulled on some waders and hopped in the stream to collect macroinvertebrates! Macroinvertebrates have relatively long lifespans and don’t migrate – the more diverse the macroinvertebrates found are, the healthier the stream is!
Armed with D-nets, the students ignored the freezing water and took 3 kicks (samples), determined to solve the water quality mystery! Just by peering in the tub it was evident just how many macros we had found! We didn’t even need to squint to recognize all of the stoneflies swimming around alongside a Sculpin!
Once we had our sample, the fun part began! After a random sub-sample, we began to identify the macros that we found in the stream! Since Mayflies are more tolerant to stream pollution, we found a lot of Small Minnow Mayflies. We also found a few older Yellow and Golden Stoneflies which is a great sign for stream health! All 4 of our feeding groups: shredders, collectors, scrapers, and predators were represented in our samples.
It looks like we have a lot of evidence that points to Eagle Creek being pretty healthy! We can’t wait to see how Rinearson Creek compares.
The mystery is almost solved…stay tuned…