Water Quality. Good water quality is important for the plants and animals of the riparian community. Fish, aquatic insects, amphibians, and perhaps endangered species could easily be affected by poor water quality. High bacteria counts have been observed in the Park. In 1972, E. coli counts as high as 16,000 ppm contributed to a die off of several mammal species. The US Public Health Service identified the culprit as infection due to the bacterium genus Arizona (closely related to genus Salmonella).