Saltwater intrusion is a global threat to coastal freshwater ecosystems linked to climate and anthropogenic change. Alterations to coastal landscapes can lead to saltwater intrusion events. Sapelo Island has had an extensive history of landscape alteration for agriculture, but the movement of salt inland has impacted its recent cultural revitalization. Intrusion events are expected to increase in frequency and magnitude due to rising sea levels and storms. Salinizing freshwater habitats are at risk for diversity loss, impacting humans relying on these habitats, and a potential positive feedback effect on global warming through the loss of carbon sequestration. While species have varying tolerance levels to salt, many are incapable of migrating to other habitats, resulting in a higher chance of eventual extirpation or extinction. Denser saltwater also puts more pressure on benthic organisms in intruded areas, like macroinvertebrates that higher trophic levels rely on for food. Previous studies show that saltwater intrusion negatively affects freshwater communities and the essential ecosystem process of decomposition. We hypothesized freshwater habitats exposed to an increasing gradient of salinity would exhibit reduced diversity and function (e.g., lower decomposition rates). We monitored hydrology, measured decomposition rates, and sampled benthic macroinvertebrate communities to assess potential impacts of saltwater intrusion in sites with varying salinities. At the site with the highest salinity, preliminary data show levels higher than oceanic salinity on the benthos and lower salinity levels at the surface, indicative of halocline presence. This site had less diverse benthic macroinvertebrate communities, less crayfish abundance, an absence of amphibians, and the presence of estuarine fishes. Preliminary decomposition data shows overall lower rates of decomposition (slope = 3.170×10⁻⁵), with a higher rate in the freshwater reference site (slope = 3.403×10⁻⁵). This study outlines problems associated with saltwater intrusion on freshwater habitats tied to anthropogenic impacts and this data should help the management of imperiled habitats across the coast.