Students from Ms. Schoelen’s 5th grade class at Pescadero Elementary took a field trip to the San Gregorio Watershed recently to study stream and lagoon environments. They visited two sites, and had the opportunity to perform water quality tests at two very different locations.
The first site was on La Honda Creek at Playbowl. This is a densely wooded area with meandering creek and good spawning gravels and water quality. Stream flow was low prior to winter rains, making it a good time for students to safely measure air and water temperature, turbidity, conductivity (salinity), and pH.
The fifth graders were provided data sheets on which to record observations as well as results of their testing. Observations include weather conditions, flow rate in the creek, woody debris, habitat conditions such as boulders, gravels and fish barriers. No fish were observed, but students were able to see both artificial and natural structures in the stream channel. Natural structures don’t normally create a barrier to fish passage, but artificial ones can.
Stream monitors from the San Gregorio Environmental Resource Center (SGERC) guided students through the instruction and use of basic sampling equipment. Turbidity, or the cloudiness of the water, can be observed by looking at a Secchi disk in the bottom of a long tube of water. Meters and probes were used to measure temperature and conductivity. pH was measured with a test kit that adds reagent to the water sample, and is then compared to a color wheel to determine pH level.
Before leaving Playbowl there was time for a quick game of tag in the woods.
A short bus trip to San Gregorio State Beach, and we were able to observe a completely different environment, but one that is crucial to fish survival – the lagoon. SGERC recently assisted in the installation of an interpretive panel at this location that describes proper lagoon function and the species that depend on it. This was a good place to begin this visit. In addition to discussing the importance of the sandbar and the complicated environment and interface of fresh to salt water, students were able to repeat their basic water quality sampling. Also at this site more sophisticated monitoring equipment was shown, and a quick demonstration of Dissolved Oxygen measurement, a critical parameter for fish survival.
After sampling and observations were completed, it was lunchtime!
SGERC would like to thank the teachers, parents, students, and principal of Pescadero Elementary for their efforts to make this field trip possible. We’d also like to thank Cuesta La Honda Guild and California State Parks for permission to visit these sites, and also George Cattermole and CWC for transportation funding. This program was sponsored by SGERC as part of their education programs and continuing efforts to monitor and improve conditions in the San Gregorio Watershed.
(Also published in The La Honda Voice, November 2017.)
Protecting the San Gregorio Watershed.