Beneath the rocks and rushing water of our Sierra streams lives a hidden world of insects, worms, snails and other fascinating creatures. These Benthic Macro-Invertebrates, or BMIs, may be small, but they can tell us an important story about the health of our waterways.

One of the most fascinating is the hellgrammite – the underwater larva of the dobsonfly. These strange and wonderful creatures can spend up to two years living underwater, hunting, hiding under rocks and hanging on through floods and changing conditions.

We’re excited to welcome Stan Iverson, author of Hector the Hellgrammite: The Life Cycle of a Dobsonfly, to introduce us to this fascinating little world. Stan isn’t just writing about these creatures. He is the founder of the Watershed Education Summit, a hands-on program that has brought generations of high school students into local streams to investigate water quality and watershed health. His book grew out of that passion for making watershed science fun, approachable and something you can experience firsthand.

Come meet Stan and learn about the amazing creatures that call our streams home, and discover what these tiny residents can tell us about the health of the water we all depend on. You may never look at a stream quite the same way again!