Until recently, river management has largely focused on water and how to withhold, contain, or withstand the force of its flow within a stream channel. However, it is important for understanding stream processes to realize that streams and rivers are not only moving water--streams also move sediment and woody debris from mountain peaks to the sea. Human land uses that significantly alter the ability of a creek to transport water and sediment will likely cause a stream to become unstable and increase the likelihood that catastrophic erosion or sedimentation may occur during a flood event.