National Park Service health-risk determinations:
E. Coli Levels
Low risk: 177 colonies per 100 ml of water. Swimming, diving, wading has a LOW chance of getting sick. The water is in full compliance with recreation water quality criteria.
High risk: 234 colonies per 100 ml of water. Contact with the river is NOT recommended if the level is High Risk. A person in direct contact with river water has an increased risk of getting sick. The water quality does NOT meet federal recreation water-quality criteria.