Nathan Myers Learn to properly read the white-water rapid rating system to gauge the difficulty level of the river before embarking upon a rafting trip. Read the European scale from I to VI, with I being the easiest and VI being unnegotiable. Read the American scale from 1 to 10, with 1 being the easiest and 10 being very dangerous. Understand that different water levels can affect the rating of a rapid one way or the other.
Some rapids are more dangerous in low waters, and some are more dangerous in deeper waters.
Know the rating for each rapid you'll encounter on your rafting trip before you embark. Know the rating for that particular time of year, for that particular year. Check the dates and ask the rangers. Always plan and prepare well before a rafting trip. Make sure your raft is outfitted for all types of emergencies.