Join the park naturalist at the spillway anytime from 2pm-4pm or 6pm-7pm. She'll demonstrate methods for collecting macroinvertebrates, have some on hand to view, and will have tools for you to explore on your own. 

Update: Due to inclement weather, Ms. Jean will not be at the spillway to conduct the 6PM demos. Visitors can come to the James Kell Visitor Center to view specimens that were collected during the 2PM-4PM demos.