Spring inputs enable the South Llano River (SLR), a medium-sized stream in central Texas, to maintain elevated baseflows even during periods of drought. As a result, this ecosystem supports high aquatic and terrestrial biodiversity and provides abundant natural contributions to people; however, multiple major threats challenge the sustained ecological integrity and water quality in the SLR. One critical threat is posed by invasive feral hogs, which are known to negatively affect the aquatic-terrestrial interface by trampling substrate and removing vegetation, drastically impairing the structure and function of the riparian zone. To examine the impacts of feral hogs on channel conditions and benthic macroinvertebrate communities in the SLR, we surveyed a 24-km stretch containing clean riffles (‘hog-absent’; N=18) and riffles adjacent to hog wallows (‘hog-present’; N=25) for water quality (i.e., dissolved oxygen, conductivity, temperature, chlorophyll A, turbidity, and dissolved nitrogen/phosphorous), structural components (i.e., wallow area, streambank slope, riffle area, thalweg and average depth, presence of prominent habitat features, and dominant substrate), and benthic macroinvertebrates. We observed alterations in water quality and riffle structure resulting from the presence of hog wallows; structural changes to the SLR have caused a shift in the benthic macroinvertebrate community to include a higher abundance of generalist species that can tolerate poor water quality. This work demonstrates linkages between aquatic and terrestrial ecosystems and the large-scale effects invasive species can have across this gradient, and our work represents a call to action for increased invasive species management and the protection of critical habitats in central Texas.