Human needs have drastically altered the natural flow regime of many rivers. Aquatic invertebrates that have morphological, life history, or behavioral adaptations that allow them to survive and reproduce under natural flow conditions could be adversely affected by these changes.  With the current regulation of rivers, it is important to understand how flood and flow variability affects groups of aquatic organisms.  There is a paucity of quantitative information on the link between flood and flow events and the population responses of benthic invertebrates.  We collected invertebrates in the Bill Williams River (BWR) in Arizona in three sites below Alamo Dam before and after an experimental flood release in 2006, and in a reference river upstream of the dam.  The BWR is ideal for performing controlled experiments because floods with specific parameters are scheduled in advance.  Ephemeroptera (mayflies) and Trichoptera (caddisflies) increased in diversity below the dam after the flood release (an average of 1 more taxon), and percent of organisms with an aerial life stage also increased (an average of 17%).  We propose a simple conceptual model, using flow variables and target taxa with varying life history patterns, that may be a useful tool for theoreticians and managers alike.