From the Classroom

Water Quality Testing at Carpe Diem and Sonoma Mountain High School

Recently, Jessica Dennen’s science classes at Carpe Diem and Sonoma Mountain High School tested their local water. Carpe Diem High School walked down to the Petaluma River at a testing location near Apple Box; while Sonoma Mountain High School walked to Adobe Creek. Both classes tested for nitrates, phosphates, dissolved oxygen, along with the pH level, air and water temperature, salinity, and conductivity.  Their results can be viewed on the Watershed Atlas at,

This was the first outing for Dennen and her science classes, and the first testing of Adobe Creek’s water since the recent California rains. John Shribbs joined Dennen’s class on the walk down to the Petaluma River and gave a brief talk about the river’s tidal influence. Before splitting into groups to begin testing, Shribbs opened the discussion to hear student’s thoughts on the potential results.  Students hypothesized that the salinity level would be high due to the tidal influence and also thought the phosphate and nitrate levels might be high given the recent rainfall after a stretch of sunny days in which homeowners likely fertilized their lawns in preparation for spring. The students who walked down to Adobe Creek had similar thoughts about the phosphate and nitrate levels, especially given Adobe Creek’s proximity to Adobe Creek Golf Course. Once the data was collected, it was imported into the Watershed Atlas Database’s Water Quality Monitoring Layer.

Dennen expects to get out with both classes again before the school year is complete. In doing so, her students can compare their results and note any differences in the water quality.


By Dylann Moore