Data from surface water and sediment nutrient processing experiments associated with the Maumee River (Toledo, OH) during the 2021 growing season

River-to-lake transitional zones or rivermouths are biogeochemically active sections of the aquatic continuum that are often understudied compared to their adjoining environments. Internal nutrient loading from these transitional zones may be a considerable source of nutrients to lakes and disconnect upstream management initiatives from in-lake improvements. To contextualize internal nutrient loading by rivermouth sediments, we conducted sediment core incubations and nutrient assays at three timepoints over a growing season (2021) in the Maumee Rivermouth (Toledo, OH). These data can be used along to estimate nutrient processing rates within the Maumee Rivermouth.