The International Scale of River Difficulty / Learning to Fish Rivers & Streams

International Scale of River Difficulty

Before you load up the ‘ol kayak and attack a river – make sure you do some research to see if you can find information explaining the level of difficulty of its rapids. In an effort to standardize the terminology surrounding rapids, The International Scale of River Difficulty was developed.

Keep in mind that the water stage (whether the water is high and fast or low and slow) may have an impact on the difficulty level. For instance, high water can turn Class 2 rapids into Class 3 – or even 4 in some circumstances. If you have any hesitation or uneasy feelings about a section of river or certain rapids, do what you can to scout ahead from shore before attempting to make a run.

The Six Grades of White-Water Difficulty:

Remember: no matter what class of rapid you plan to traverse, a personal flotation device like a lifejacket is absolutely critical – do not leave home without one!

Personal Flotation Devices - PFDs
Personal Flotation Devices – PFDs

The following images can be found in: The Freshwater Angler™: Fishing Rivers & Streams

Class 1: Easy rapids with small standing waves and few obstructions. Under high water conditions they may disappear completely.

Class 1 Rapids Example
Class 1 Rapids Example

Class 2: Standing waves that may reach a height of 3 feet. Some maneuvering is required for safe passage. As a general rule of thumb – anglers in small fishing boats should avoid any rapids greater than Class 2.

Class 2 Rapids Example
Class 2 Rapids Example

Class 3: High, standing waves are capable of swamping an open canoe or small boat. Extensive maneuvering may be required to follow narrow chutes between boulders or turbulent areas.

Class 3 Rapids Example
Class 3 Rapids Example

Class 4: High, irregular standing waves along with constricted passages and blind drops require a rubber raft, decked canoe, kayak, a maneuverable deep-sided boat or jet boat.

Class 4 Rapids Example
Class 4 Rapids Example

Class 5: Hazardous to life because of long, violent rapids and steep drops or falls, which may require a complex route to navigate. These rapids are runnable only by experts with a raft or fully decked boat.

Class 5 Rapids Example
Class 5 Rapids Example

Class 6: The same hazards that are present in Class 5 rapids, but more severe. Even whitewater experts consider Class 6 rapids nearly impossible to navigate. These torrents pose a great risk to life.

Class 6 Rapids Example
Class 6 Rapids Example

Moving Forward

This summer, I will not be taking my jon boat out to try to navigate any rapids. We might do a bit of kayaking, but the goal will be to hike and explore as many winding streams as possible. Still… this is very important knowledge to have, even if it is just put into play from a research perspective.

2020 Fishing (Resized for Gallery)

It’s cold outside as I write this… but soon… we fish… tight lines!

NEXT SECTION: Top 5 Baits for Streams & Rivers

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“When will those bass come back shallow?!”
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