Riffle, run, pool, and backwater are terms related to stream or river ecology. Our project site has a river that runs along the property edge, which makes this terminology important to the management of the riparian area. A riffle is an area of stream or river where the flowing water surface is visibly broken by small rocks, boulders, or gravel. A run is an area with no water turbulence, but the water flows at a rapid pace. Runs are commonly found downstream from riffles and are deeper than riffles. A pool is an area of deeper water and slower currents. Backwater areas are out of the main current flow of the river and are usually stagnant.