Classifications of Rapids for Whitewater Rafting in Colorado

Our whitewater rafting guests often ask us questions about river water depth, the kind of rapids they’ll be rafting through, and what the whole class system means as they prepare for their first or even 50th rafting adventure with us.  So we thought we’d bring some clarity to the question and give you an overview of rapids classifications for whitewater river rafting … and provide some expertise on the topic.

Factors in Rapids Classifications

Rapids and the classifications of whitewater vary due to different circumstances: water levels can be high or low depending on the amount of snowmelt and vary as weather conditions change. Our beautiful snowcapped Rocky Mountain peaks melt and flow into Colorado streams, rivers, and reservoirs starting in earnest in May, which is the start of the spring runoff. The start of rafting season usually kicks off in the middle of May as the weather warms up, and tends to max out the highest water flow throughout Colorado depending on altitude and distance from the deepest snow pack. In general, spring snowmelt brings higher water and higher levels of difficulty while running our rivers primarily because the water runs fast and furious, forcing quick decisions as river features change. Water levels fluctuate dramatically throughout the summer and our guides can even see differing conditions between a morning run and an afternoon trip when water levels are in a high state of flux.

What are Rapids Classifications?

Rapids themselves are graded on a class system starting at 1 and progressing to 6.  The higher up the scale they go, the more difficult and the more consequential the stretch of water will be. As an example, there are many variables that can change, either upgrading or downgrading the classification of a rapid. Rapid variables include water levels, objects, under

cut rocks, and strainers (like a log jam). Certain features within a river naturally are more difficult and make it more challenging to navigate. For example, Brown’s Canyon is less difficult to navigate than the Numbers section of the Arkansas River. This is why it’s so great to have an experienced raft guide to help you experience Colorado’s most beautiful areas safely. This, as well as having a great day of fun on the water, is what you experience when rafting with Kodi Rafting. Let’s explore the difference between each classification of whitewater in even more detail than is outlined on our website’s rapids classification page.

Class I is flat, easy moving current. Minimal moves, minimal difficulty. The most difficulty you experience on this level of river is navigating around bends and avoiding shallows, perhaps pulling into eddies. Think of this as a leisurely float down a river. Class I is about staying with the current and literally going with the flow.

Class II is moving current with slightly more difficulty and has specific moves that your raft guide needs to make in order to navigate the river efficiently. The difference between class I and II is the necessity to maneuver around objects or shallow sections. Class II is a moderate river trip and great for families. A bit more adventure and splashing without high anxiety. Join Kodi for class II trips on the Upper Colorado, Blue River, or Clear Creek for 1/2 day or full day trips.

Class III is a moderately difficult section of river, with slightly higher consequences, and with more difficult moves to be made by your raft guide. There is typically faster moving current than class I and class II, and there can be objects and things to avoid along your path. Some of these potential objects could impede your raft, or even flip you over if not navigated around properly. Class II, & III trips are your typical family trips with somewhat older or more adventurous family members. If you’d like to experience a higher level of family excitement, book our Arkansas 1/2 day or full day trip with Kodi at our Buena Vista location, or the Clear Creek Canyon trip departing from Idaho Springs to enjoy class III rapids.

Class IV is a difficult stretch of river. A class IV section has fun, fast and technical rapids. Standing waves, big rocks, turbulent water, and difficult features are all things you will find on Class IV river runs. These rapids are active: multiple objects, multiple variables and multiple moves involved in order to navigate safely. The Numbers of the Arkansas River, and Clear Creek are examples of exciting options Kodi offers to raft this kind of trip, for a high level of excitement and challenge.

Class V is for experts only. This is the most challenging level for a commercially rafted trip. Class V includes lots of maneuvering, with fast consequential moves. Teamwork, communication, coordination, and strong paddling are needed to safely navigate Class V sections of whitewater. These rapids can have large drops, violent currents, and extremely steep gradients – and loads of excitement!

Class VI is extraordinarily difficult or non-runnable sections of river. Rafters face extreme imminent danger. Think cliff drops, big rocks, and scary aspects of challenge. Class VI level rapids are never run commercially, and are often walked around by rafters to avoid them.

So whatever level of challenge, splashes, and excitement you desire, Kodi Rafting can deliver. From calm float trips to expert runs to go big, give us a call to book the rafting adventure that suits your family, group, or yourself!

Call to book your whitewater adventure with us today at 877-747-RAFT or book online here. See you on the river! 


KODI’s Rivers: An Overview

Arkansas River

The Arkansas River starts as a patch of melting snow in Leadville, Colorado, a city rich in mining history and famous for its 10,200-foot elevation. The Ark (as locals like to call it) gains momentum as it flows past some of the biggest mountains in Colorado, benefiting from their abundant snow melt in the spring and summer. From its headwaters, the Arkansas River deliver more than 100 miles of whitewater, making it the most popular river for rafting in the American West. The river’s appeal lies in its wide variety of trips and easy accessibility.

Arkansas River Raft Trips

Blue River

The Blue River is roughly 65 miles long and is a tributary of the mighty Colorado River. Flowing from the Dillon Reservoir Dam just above the town of Silverthorne to the confluence with the Colorado River at Kremmling, the Blue River is easily a candidate for Colorado's most scenic river. Lined by cottonwood trees and crowned by the rugged Gore Mountains, the Blue River winds a scenic course through ranch land, and its public access points are popular among anglers and kayakers alike.

Blue River Raft Trip

Clear Creek

Clear Creek is a tributary of the South Platte River that flows through Clear Creek Canyon in the Rocky Mountains directly west of Denver. It descends through a long gorge to emerge on the Colorado Eastern Plains where it joins the South Platte. Clear Creek is unusual in that it is a stream named "creek" fed by a stream named "river."

Clear Creek Raft Trips

The Upper Colorado River

The Upper Colorado River Basin, defined by the river network above northern Arizona, is comprised of four states—Colorado, New Mexico, Utah, and Wyoming. These states contribute to the vast majority of the water coming into the Colorado River Basin, primarily through winter snowpack.

Colorado, specifically, is known as the Headwater State because it’s home to the headwaters of four major rivers: Platte, Arkansas, Rio Grande, and Colorado. The Colorado River flows west out of the slopes of Rocky Mountain National Park and connects to several tributaries, including the Animas, Eagle, Dolores, Yampa, Blue, and Roaring Fork Rivers.

Upper Colorado River Trips

Ten Mile Creek

Ten Mile Creek is a stream in Summit County. It rises above Copper Mountain Ski Resort and follows next to Interstate 70 for several miles before emptying into Dillon Reservoir. The creek and the paved trail that follows alongside it are easily visible from Interstate 70 between Frisco and Copper Mountain Ski Area.

Ten Mile Creek River Trip

Dolores River

A long and winding river in southwestern Colorado, the Dolores flows through canyons packed with enormous ponderosa pine and high sandstone cliffs in brilliant oranges and reds. The river continues its journey from the alpine scenery into the high desert and through canyons dotted with amazing white water, ancient ruins, and untamed wilderness.

Dolores River Raft Trip


Colorado’s Upper Colorado River

The Colorado River provides water to nearly 40 million people, flows through nine National Parks, and drives a $1.4 trillion economy. If the Colorado River basin were a country, it would be the world’s 7th largest by economic output.

The Upper Colorado River Basin, defined by the river network above northern Arizona, is comprised of four states—Colorado, New Mexico, Utah, and Wyoming. These states contribute the vast majority of the water coming into the Colorado River Basin, primarily through winter snowpack.

Colorado, specifically, is known as the Headwater State because it’s home to the headwaters of four major rivers—Platte, Arkansas, Rio Grande, and Colorado.

The Colorado River flows west out of the slopes of Rocky Mountain National Park and connects to several tributaries, including the Animas, Eagle, Dolores, Yampa, Blue, and Roaring Fork Rivers.

KODI Rafting runs raft trip on the Upper Colorado River out of Kremmling. The water we raft runs through a unique and beautiful landscape known for its diverse water features, abundant wildlife, and cultural landscape.

Notable sections of the Upper Colorado include Parshall to Blue River, Gore Canyon (where you’ll find extreme class IV and V whitewater), Pumphouse to State Bridge, and State Bridge to Dotsero.

Pumphouse to State Bridge is the most popular section because of its combination of placid waters through pastoral heritage ranchland and more challenging class II and class III rapids in the intervening canyons.

The Colorado River cuts a path through the Gore Mountain Range at the beginning of its long trip to the Pacific Ocean. There are natural hot springs, historic cabins, swimming, hiking, and beautiful scenery. The river is ideal for first time participants, families, and groups of all ages and abilities. The Upper Colorado River is easily accessible from many resorts, including Breckenridge, Vail, Steamboat Springs, and Winter Park.