Benthic Macroinvertebrates as Indexes of Water Quality in the Upper Cuyahoga River

Indices of water quality for the Cuyahoga River of northeastern Ohio, based on benthic invertebrate community composition, indicate a range in water quality along the river. Overall water quality is relatively high compared with areas of the river below Akron and to most nearby river systems. Highest quality areas are located in the most headwater region and in the lowermost region near Lake Rockwell. These areas are characterized by a large number of taxa, moderate density of organisms, high ratios of scraper-grazers to detritivores, high ratios of amphipods to isopods, and less than 1% organic pollution-tolerant organisms. Moderate degradation of water quality due to organic sedimentation in these areas is indicated by large proportions of organic pollution-facultative organisms.