Swanson, F. J.; Graham, R. L.; Grant, G. E. 1985. Some effects of slope movements on river channels. In: Proceedings of the international symposium on erosion, debris flow and disaster prevention; 1985 September 3-5; Tsukaba, Japan. Tokyo: [Publisher unknown]: 273-278.
The geomorphic response of a channel to slope movements depends on the rate of colluvium delivery from hillslopes relative to the rate of removal by fluvial processes. For slope movements ranging from extremely slow to slow (less than 1.5m/mo), the balance between slope and fluvial influences can be considered in terms of the channel constriction ratio., defined as the ratio of slope movement to channel width, expressed as %/year. Sites with faster constriction ratios may experience more frequent stream bank instability and sediment production. Rapid slope movements discharging large volumes of colluvium into channels can form dams. Dam volume, river discharge, and size distribution of dam material determine the potential for dam failure and release of water from impounded lakes. the implications for hazard prediction and mitigation are discussed.