Where IS the Watershed Anyway?

On March 15th, 2018, As preparation for future excursions I met with the 75 students of the Pre-AP Biology class at Flagstaff High School Alpine program to learn about the watershed of Flagstaff.


Over the course of 4 class periods, all 75 students learned to delineate ridges, drainages, and the outer boundaries of our Flagstaff watershed on laminated topographic maps. In doing so they learned to interpret topographic lines as uphill or downhill and how to identify other symbols like elevation markings and how to locate their school on a USGS map. Skills that will help them later with their navigation endeavours.


Once the watershed has been laid out, we talked about the different types of pollution that can enter and impact a watershed. Specifically we learned about point source vs. nonpoint source pollution as well as the understanding that sediment from erosion is a form of pollution too! As students studied the map they were able to identify large areas of potential non-source pollution as well as explain how trails, when poorly constructed, can contribute to sediment pollution in the watershed. This gave them a beginning context for the importance of trail stewardship, maintenance and volunteerism.


The students were super interested to see how water flows through our community and seemed to really connect with the visual element of drawing the drainage on a map. They ended the class with a lively conversation about what they might do to limit nonpoint source pollution if they were a city planner. It was an exciting class with many ah ha moments. Now to take our learning outside!