9553130 Johnson The research is primarily in the areas of reliability and environmental hydraulic engineering, involving problems of stream channel erosion around bridge foundations, including erosion due to local scour, channel restorations and modifications, and lateral migration of streams, and the reliability of the bridges as these erosional processes occur around the foundations. Additional studies will develop a better understanding of the erosional process, as well as develop criteria for the design and preventive maintenance of pier foundations. Studies will examine the effect of the duration of the peak storm discharge on the scour depth. ***