The Department of Energy's (DOE's) Oil Recovery Field Demonstration Program was begun in 1992 to maximize the economically and environmentally sound recovery of oil from known domestic reservoirs and to preserve access to this resource. Cost-shared field demonstration projects have been initiated for geologically defined reservoir classes. The reservoir classes have been ranked by their potential for incremental recovery and their risk of abandonment. This document defines the characteristics of the fifth geological reservoir class in the series, fluvial/alluvial reservoirs. The reservoirs of Class 5 include deposits of alluvial fans, braided streams, and meandering streams. Deposit morphologies vary as a complex function of climate and tectonics and have a high degree of fluid-flow heterogeneity due to extreme variations in water energy when the deposits formed.