Freshwater mussels are ecosystem engineers whose filtering, nutrient cycling, habitat modification, and energy transfer functions enhance freshwater habitat stability, nutrient availability, and food-web dynamics. Unfortunately, 45% of mussel species are extinct or near extinction, with 74% of remaining North American species threatened with extirpation. This presents an opportunity to improve water quality of stream ecosystems and revitalize mussel populations by establishing their restoration as a best management practice. However, there are still questions surrounding how reintroduction of mussels to a freshwater ecosystem will alter macroinvertebrate communities and their function, especially in urban streams. As macroinvertebrates are the primary method of stream water quality assessment in the United States, it is imperative to understand how mussels influence macroinvertebrates as it will directly affect streams’ health designation. We deployed 1,500 adult Eastern elliptio (Elliptio complanata) mussels in two, 200m restored urban stream reaches in Reston, VA. We sampled benthic macroinvertebrates in reaches before introduction (August 2023) and will continue to sample them through 2027. Our first objective will be to analyze the effect that stocking mussels in urban streams has on macroinvertebrate community composition, functions, and water quality through a Before-After Control-Impact design. We predict that (1) macroinvertebrate density (individuals/m2), biomass (mg/m2), and taxa richness will increase one year following mussel introduction; (2) benthic consumers and predators increase while filter feeders decline; and (3) mussels will result in increased scores in the benthic index of biotic integrity. These results will then be compared to reaches with and without mussels to analyze how mussels interact with other invertebrates to influence community and ecosystem dynamics. We will provide the preliminary research for further exploration into the mechanisms behind mussel and macroinvertebrate food-web interactions, developing a better understanding of how mussels influence water quality evaluations.