Aquatic resources along the Little Missouri River near Theodore Roosevelt National Park, North Dakota

Tronstad, Lusha

Water quality in the Little Missouri River, North Dakota is potentially threatened by high concentrations of fecal coliform bacteria and a water diversion. Fecal coliform concentrations are above the standards for recreation in one reach of the Little Missouri in and near the South Unit of Theodore Roosevelt National Park. Concentrations are near the recreation water quality standard in and near the North Unit of the Park. Additionally, a water diversion was built upstream of the South Unit of Theodore Roosevelt National Park, which may alter the hydrology of the river. To investigate ecosystem quality along the Little Missouri River, I collected basic water quality, fecal coliform concentrations, Escherichia coli concentrations, and aquatic invertebrate samples at four sites. Basic water quality was similar among sites. Fecal coliform concentrations were above the water quality standard for recreation at all sites, and E. coli exceeded the limit at the downstream site. Aquatic invertebrate samples indicated that the sites upstream of the South Unit of Theodore Roosevelt National Park were in good condition according to the Macroinvertebrate Biotic Integrity Multimetric Index of North Dakota. However, individual metrics suggested that the water diversion may be impacting the river. The Little Missouri River at the North Unit of Theodore Roosevelt National Park had lower ecosystem quality according to the Macroinvertebrate Biotic Integrity Multimetric Index of North Dakota and individual metrics, but the lower score may be at least partially due to sand substrate. Fecal coliform concentrations are high in the Little Missouri River, which may be due more to livestock grazing than municipal waste. To reduce fecal coliform concentrations, land management practices will likely need to change throughout the affected watershed and within Park management actions will likely have minimal effect on concentrations. To understand the ecosystem quality of the Little Missouri River at the North Unit of Theodore Roosevelt National Park, a more intensive study should be conducted.

Aquatic resources along the Little Missouri River near Theodore Roosevelt National Park, North Dakota

Series