Stream flow is the primary abiotic factor influencing stream ecosystem function. Physical forces associated with the flow change habitat structure, translocate materials, and can affect dispersal ability and behavior of an organism. Macroinvertebrates fulfill functional roles within a stream that play a profound role in nutrient cycling and primary productivity. As a result, much of the ecological integrity of a stream is interdependently linked to this interaction of flowing water and macroinvertebrates. However, natural systems have increasingly been under siege through flow alterations in the form of dams, land use, and storm events through global climate change. Organisms may show morphological differences, as a plastic response to physical forces associated with flow alteration. Plasticity has been documented in fishes and the same may be observed in other stream biota. Our goal with this project is to help elucidate the direct and indirect pervasive effects associated with the natural flow regime on sensitive and indicative (EPTO) macroinvertebrates. How organisms respond to flow can provide useful taxon specific information for water resource management and enhance our interpretation of adaptations to flow that may be useful in the context of global climate change.