Stonefly nymphs live under these rocks. That means the water is clean. They only survive in cold, well-oxygenated water. Find one clinging to the underside of a riffle rock and you're reading the river — no lab required. Lose them, and something upstream has changed. The same rivers people raft, paddle, and wade all summer are the ones these nymphs call home. Clean water isn't just scenic — it's a whole system working. What's the closest waterway to you? * For transparency: this video was edited with the help of AI. #unitedbyblue #saveourwaters #worthsaving #outdoorlife #whitewaterrafting