Techniques for studying the physical effects Bhowmik, N. G., A. C. Miller, and B. S. Payne. 1990. Techniques for studying the physical effects of commercial navigation traffic on aquatic habitats. U.S. Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. Technical Report EL-90-10. Reprinted by U.S. Fish and Wildlife Service, Environmental Management Technical Center, Onalaska, Wisconsin, January 1993. EMTC 93-R007. 129 pp. NTIS #PB94-151446) ABSTRACT The primary objective of this report is to outline procedures that can be used for the measurement and analyses of physical data to measure changes that are generated with the movement of navigation traffic in large rivers. Part I of the report contains summaries of recent investigations of navigation studies and basic considerations in the extrapolation of the data for system-wide application. Part II provides a description of the various hydraulic, sediment transport, and vessel-induced parameters that need to be considered in navigation studies. Some theoretical backgrounds are given for velocity fluctuations, turbulence intensity, velocity distributions, and sediment transport characteristics of rivers. Part III considers the basic evaluation that must be done before collection of field data. Part IV describes instruments that are necessary to collect physical, hydraulic, and sediment transport data for a river. Part V discusses development of plans for data collection and analysis. Methods for studying pre- and post-navigation periods are also presented. Data collection and analyses pertain to physical impacts to the main channel and channel border, as well as to side channels or inlets to backwater lakes. Part VI outlines the procedure that can be followed for the analysis of the data. This includes an evaluation of the field sites, variability of flows, including velocities, movement and deposition of sediments, effects of recreational boating, and changes in bank erosion rates. This report can serve as a guide for the development and implementation of field measuring techniques for the determination of the physical changes associated with the movement of navigation traffic in an inland waterway. KEYWORDS navigation traffic, physical changes, velocity, sediment, waves, drawdown, Mississippi River, large river, measurements