Before you enjoy Idaho's swift waters it is important to fully appreciate all they have to offer and respect the boundaries they set forth for us. Please review this information to make sure you are fully prepared.
Before you select a whitewater guide or outfitter, get answers to these questions:
From the American Whitewater Association
Whitewater rivers contain many hazards which are not always easily recognized. The following are the most frequent reasons people are injured or killed. High water. The river's speed and power increase tremendously as the flow increases. This causes the rapids, which is the thrill for whitewater enthusiasts. It also makes for the most hazardous conditions. Reliable gauge information will help your guide be prepared for the dangers including the additional risks posed from melting snow, hard rain, and upstream dam releases which may greatly increase the flow.
Cold Temperatures. Cold drains your strength and robs you of the ability to make sound decisions on matters affecting your survival. Cold water immersion, because of the initial shock and the rapid heat loss which follows, is especially dangerous. With water temperatures of less than 50 degree f., wear a wetsuit or drysuit for protection if you should need to swim. Next best material is wool or pile clothing under a waterproof shell. NEVER COTTON. IT WILL WEIGH YOU DOWN.
Strainers. brush, fallen trees, bridge pilings, undercut rocks or anything else which allows river current to sweep through can pin boats and boaters against the obstacle. Water pressure on anything trapped this way can be overwhelming. Rescue is often extremely difficult. Pinning may occur in fast current, with little or no whitewater to warn of the danger.
Dams, ledges, reversals, holes, and hydraulics. When water drops over an obstacle, it curls back on itself, forming a strong upstream current which may be capable of holding a boat or swimmer. Some holes make for excellent sport. Others are proven killers. Paddlers who cannot recognize the difference should avoid all but the smallest holes. Hydraulics around man-made dams must be treated with utmost respect regardless of their height or the level of the river. Despite their seemingly benign appearance, they can create an almost escape-proof trap. A swimmers only exit from the "drowning machine" is to dive below the surface where the downstream current is flowing beneath the reversal.
Broaching. When a boat is pushed sideways against a rock by strong current, it may collapse and wrap. This is especially dangerous to kayak and decked canoe paddlers; these boats will collapse and the combination of indestructible hulls and tight outfitting may create a deadly trap. Even without entrapment, releasing pinned boats can be extremely time-consuming and dangerous. To avoid pinning, throw your weight downstream towards the rock. This allows the current to slide harmlessly underneath the hull.
Boating alone is discouraged. The minimum party is three people or two craft. HAVE AN HONEST knowledge of your boating ability, and don't attempt rivers or rapids which lie beyond that ability.
Divided into six classes, the whitewater rating system attempts to provide a uniform set of evaluation criteria for rivers. Bear in mind that changes in river levels can dramatically affect a river's difficulty rating.
Class I: Easy
Fast moving water with small waves; passages clear; no serious obstacles. Risk to swimmers is slight; self-rescue is easy.
Class II: Novice
Straightforward rapids with wide clear channels which are evident without scouting. Occasional maneuvering may be required, but rocks and medium-sized waves are easily avoided by trained boaters. Swimmers are seldom injured and group assistance, while helpful, is seldom needed.
Class III: Intermediate
Rapids with moderate, irregular waves which may be difficult and can swamp open canoes. May require complex maneuvers in fast current and good boat control in tight passages or around ledges. Large waves and strainers are often present. Strong eddies and powerful current effects are common, especially on large volume rivers. Scouting is advisable for inexperienced parties. Injuries to swimmers are rare; self-rescue is usually easy but group assistance may be necessary to avoid long swims.
Class IV: Advanced
Intense, powerful but predictable rapids requiring precise boat handling in turbulent water. Depending on the character of the river, it may feature large unavoidable waves and holes or constricted passages demanding fast maneuvers under pressure. A fast, reliable eddy turn may be needed to initiate maneuvers, scout rapids or rest. Rapids may require "must" moves above dangerous hazards. Scouting is necessary the first time down. Risk of injury to swimmers is moderate to high, and water conditions may make self-rescue difficult. Group assistance for rescue is often essential but requires practiced skills.
Class V: Expert
Extremely long, obstructed or very violent rapids which expose a boater to above-average endangerment. Drops may contain large, unavoidable waves and holes or steep, congested chutes with complex and demanding routes. Rapids may continue long distances between pools, demanding a high level of fitness. Eddies, if any exist, are small, turbulent and hard to reach. Often, several of these factors are combined. Scouting is mandatory and often difficult. Swims are dangerous and rescue is difficult even for experts. Proper equipment, extensive experience and practiced rescue skills are essential for survival.
Class VI: Extreme
These runs exemplify the extremes of difficulty. The consequences of errors are usually fatal and rescue is usually impossible. For teams of experts only, at favorable water levels, after close inspection and taking all precautions. This class does not represent drops thought to be unrunnable, but may include rapids which are only occasionally run.
Source: Chapin Clark Whitewater Safety Foundation