In this study the hypothesis that Lake Michigan water levels affect coastal wetland hydrology and soil variables was examined. Both long-term (several years) and short-term (daily) fluctuations in lake levels were influential. Short-term differences in lake level affected the distribution of plant species through anaerobic soil conditions, and resulting concentrations of nutrients influenced the distribution of plant species in coastal wetlands and beaches. Long-term fluctuations in water level resulted in different quantities of wetland and beach areas. The two time-frames were related, with long-term lake levels operating as a primary variable to influence short-term soils and plant characteristics.