Avery Walker, James Korson, Monroe Wilde, and Taylor Sanders

Fall 2025 Stream Testing

We are studying the health of Crockery Creek at the Luce Family Property.  The Luce Family Property is a creek-side property that has direct access to Crockery Creek.  This section of the stream is very sandy with a lot of vegetation on the edges, with rocks in and around the banks. Potential sources of pollution could be caused by suburban runoff, rain, sediment runoff, or old septic tanks and pipes that could lead to the stream. This section is located directly downstream of the Rvaenna Lumber Yard and other urban areas.

We tested the water for pH, conductivity, salinity, total dissolved solids, E. coli, and collected macroinvertebrates. The method we used to test for E. Coli was the left, right, and center method. This was done by taking water samples from the left, right, and center sections of the stream, then sending them off to the GVSU labs to get them tested. When collecting our macroinvertebrates, we would scuffle up sand to encourage the bugs to leave the creek bed, allowing us to scoop them up. We would also look under rocks and logs, where it was very common for the bugs to live. The water quality tests were conducted using a PCTS Testr 50. We used a turbidity tube to determine the turbidity levels. We used a GeoPack flow meter to determine the stream flow of the creek. While onsite, we wrote down the data that we collected in our field books, then we returned to the classroom and imported it into a Google form, which filled out a plot chart for us to show our data with both present and past dates. Our E. Coli levels were so high that we exceeded the highest amount possible for the test.

We analyzed the data by having Dr. Buday explain the ranges, results, and the possible causes for them. 

As a first-time testing site, the Musketawa Trail team learned that we had the first E. coli value that was higher than the detection limit that Grand Valley State University tests can measure. Bennett McAfee, the new Data Scientist at GVSU's Annis Water Research Institute, had to add an “upper detection limit” line on our plot. What this means is that the true amount of E. coli in our tests from 9/22 are higher than what we can accurately record with our tests. This is not something we were proud to learn, and we are very concerned about why our E. coli levels were so high. 

Questions we still have about the E. Coli levels of our stream site include: 

1. How would our results vary by testing before rain, during rain, and after rain? We wonder if the E. coli levels were very high on 9/22/25 because we had a very droughty summer, and had just finally experienced a rain event just before testing. 

2. Would the E. coli levels change if we tested in winter? We wonder if they would they be higher or lower?

3. Why were our E. Coli levels so high?  Was the drought a factor? Could the construction of the bridge upstream be a factor?