A Comprehensive Guide to Colorado River Rafting

March 23, 2021

By Susan Munroe

Not All Colorado River Rafting is in Colorado

And it’s not all in Grand Canyon, either. Along the Colorado River’s 1,450-mile stretch, it touches five states and Mexico and runs through at least 12 distinct sections that are ideal for paddling, rowing, and floating. Rapids and flat water, steep canyons and wide agricultural valleys, red rock and black rock, Colorado River rafting goes far beyond the boundaries of the state that shares the river’s name and the canyon that made it famous.

The Colorado River begins in Rocky Mountain National Park. Nestled in a lush valley on the western slope of the Continental Divide, it starts as a boggy trickle seeping out of La Poudre Pass Lake, northwest of Denver, Colorado. The shallow, clear water runs over cobblestones, winding back and forth through aspen and pine trees. Moose, elk, and deer roam the verdant meadows along the river. These first miles offer excellent hiking terrain and are also popular with fishermen, but the real rafting adventures begin about 60 miles downstream.

There are more than 17 dams and diversions on the Colorado River.
Although it isn’t the longest or the largest river in the United States, its water is a critical resource for communities on both sides of the Continental Divide. In the river’s first (approximately) 35 miles alone it is dammed and diverted three times: Shadow Mountain Lake, Granby Lake, and Windy Gap Reservoir pull a maximum of 310,000 acre-feet of water per year out of the Colorado River’s natural basin and send it east to supply homes and farms in Fort Collins, Greeley, Loveland, Estes Park, Boulder, and Sterling, Colorado. Many of the Colorado’s tributaries are also dammed, and their water is pumped east to Denver, Colorado Springs, and other Front Range cities. Glen Canyon Dam (which creates Lake Powell) and Hoover Dam (which creates Lake Mead) are the two largest dams on the Colorado River.

These Are the Places to Go for Colorado River Rafting:

From the Mountains…

Gore Canyon

Just west of Kremmling, Colorado, Gore Canyon makes a rocky fist, squeezing the river into what may be its gnarliest piece of whitewater. The river descends at a rate of almost 44 feet per mile through continuous Class IV and V rapids, including a 12-foot waterfall. Outfitters who run this section have stringent rules about who they will take on their trips. You have to pass a swim test, be able to follow instructions, and be capable of staying calm in stressful situations, but if adrenaline is your thing, Gore Canyon provides plenty.

Little Gore Canyon and Lower Gore Canyon

Further downstream, in Little Gore and Lower Gore Canyons, the Colorado River quiets, slipping through open ranchland and forested cliffs. Hot springs, dinosaur tracks, riverside campsites, and a few mellow (Class II–III) rapids make these sections great for 1- or 2-day family floats. It’s also possible to continue rafting all the way to the town of Dotsero, where the Colorado meets Interstate 70, although no commercial companies run this lovely, mostly calm section.

Glenwood Canyon

Downstream of Dotsero, the Colorado River parallels I-70 through open agricultural land and low, craggy bluffs. The sheer walls of Glenwood Canyon rise swiftly, compressing both the interstate and the river. The highway is an engineering marvel, with eastbound lanes cantilevered over the river and the westbound lands suspended above the eastbound. The river also executes some spectacular twists and turns. Three main sections challenge kayakers and rafters: Barrel Springs, Shoshone, and Grizzly Creek. Barrel Springs is infrequently run; it’s just downstream of the Shoshone Generating Station (see textbox) and often has either too much water or not enough. Shoshone and Grizzly Creek, however, make for a delicious, 6-mile whitewater snack. The town of Glenwood Springs is home to several rafting outfitters that offer day trips through the canyon. Some will even run you through the rapids twice! There’s also a whitewater park in the center of town, just downstream of the confluence of the Colorado and the Roaring Fork River, perfect for kayakers who want to practice surfing and pirouettes.

How the Shoshone Generating Station protects the flow of the Colorado River.
There’s a diversion dam in Glenwood Canyon that temporarily impedes the river’s progress, diverting a maximum of 1,250 cubic feet per second (cfs) of water out of the river. This water runs through the turbines of the Shoshone Generating Station to create approximately 14 megawatts of power, and then is returned to the river. This is the first diversion on the Colorado River that doesn’t transport water east over the Continental Divide to the communities on the Front Range. In fact, this diversion ensures that a certain amount of water continues west along the river’s natural course. Shoshone’s water rights date to 1902. These predate water rights owned by entities in eastern Colorado, which means that no matter what, rights-holders in the east must allow at least 1,250 cfs to flow past their intakes and down to Shoshone—and beyond, to other water users and ecosystems that depend on a westward-flowing Colorado River.

…to the Desert.

As the river descends into Grand Junction, Colorado, cottonwoods trees replace the pines, sage and rabbitbrush dot the increasingly sandy soil, and the river itself begins to take on a red, silty hue as it cuts into the soft sedimentary rocks of the Colorado Plateau. Pink and orange sandstone rises out of the landscape where the Colorado swallows up the Gunnison River (a major tributary) and then plunges headlong into the iconic red rocks that most people associate with the river. In fact, the word “Colorado” is Spanish for this very specific shade of red. We’re officially in the desert now, with 368 miles of raft-able river still to go before Grand Canyon.

Horsethief and Ruby Canyons

Horsethief and Ruby start in Loma, Colorado. These two linked canyons are extremely popular for private rafting trips, although a few commercial companies (including Holiday!) offer fully catered trips. The river is calm, with a few Class I and II rapids to keep things interesting. The canyons are stunning: smooth, sherbet-colored sandstone walls line the river and all but erase the rest of the world. Archaeological sites and natural rock arches can be found up the many side canyons along the river. Ancient black schist juts above the river’s surface in a few places: a preview of the dark, narrow gorges of Westwater and Grand Canyons. After its journey across half the state of Colorado, the river crosses the border into Utah.

Westwater Canyon

Ruby Canyon blends almost seamlessly into Westwater, which offers perhaps the best 1- or 2-day rafting trip on the Colorado River. Westwater features 18 miles of Class I–IV whitewater and a wild ride through the river’s narrowest section. Westwater is sometimes referred to as the “Little Grand Canyon” because the geology is similar: black schist laced with pink granite beneath brilliant red-orange sandstone. The 1.7-billion-year-old schist of Westwater is the same rock that is exposed in the deepest parts of Grand Canyon.

Cisco to Moab

Few people choose to float the river between Cisco, Utah, where Westwater Canyon trips end, and the wildly popular “Moab Daily,” but this 15-mile placid stretch is a great place for bird watching; the river passes irrigated fields where raptors like to hunt. The Dolores River, another major tributary, joins the Colorado in a quiet, red-walled corner of the river corridor.

Fisher Towers

As the Colorado approaches the town of Moab, Utah, it enters one of the most spectacular landscapes along its entire length. Often referred to as the “Moab Daily” or the “Fisher Towers” section, the official name for this panoramic, 20-mile stretch is Professor Valley. Dark red walls border the west side of the river, but the east side is wide open, dotted with red rock buttes, mesas, and towers, gradually rising to the green slopes of the La Sal Mountains, whose rocky, 12,000-foot summits often hold snow well into the summer months. There is an abundance of rafting companies that offer half-day or full-day trips along this section, which includes several small but splashy rapids.

Canyonlands National Park and Cataract Canyon

South of Moab, the river slows as its gradient decreases. It noses its way, irretrievably, into a network of canyons that spreads across the landscape like long, coral fingers. For more than 50 miles, it flows through Canyonlands National Park, sinking ever deeper into a red rock wonderland. It collects the water of the Green River, its biggest tributary, and then drops into the infamous Cataract Canyon. If Gore Canyon has the gnarliest whitewater and Grand Canyon has the best-known whitewater, Cataract Canyon has the wildest whitewater. At flows over 30,000 cubic feet per second, the waves in Cataract Canyon can swallow 18-foot rafts in the blink of an eye, and even 32-foot motorized rafts pick their lines very, very carefully.

The Colorado River was not always the Colorado.
From its headwaters to its confluence with the Green River, what we now call the Colorado was, once upon a time, called the Grand River. If you follow its course on a map, you’ll find nods to this historical name. There’s Grand Lake and Grand Ditch, near the headwaters. The city of Grand Junction is at the confluence with the Gunnison River. The river flows through two Grand Counties, one in Colorado and the other in Utah. When John Wesley Powell made his historic journey down the Green River, he wrote of meeting the Grand River deep in what is now Canyonlands National Park. This is where the Colorado River used to begin, at the confluence of the Grand and the Green. But in the 1920s, Colorado Congressman Edward Taylor made it a personal mission to see the Grand renamed, to link the river with the state where it begins. In July 1921, the House of Representatives passed a joint resolution to officially change the name.

Unlike Grand Canyon, in which the flows of the Colorado River are carefully orchestrated and managed by Glen Canyon Dam, Cataract Canyon is hundreds of miles downstream from any big dam and still experiences an almost-natural, big, silty spring flood. Similar to Grand Canyon, the lower reaches of Cataract are submerged beneath the sediment and still water of a reservoir: Lake Powell for Cataract, Lake Mead for Grand. At its maximum capacity, Lake Powell swallowed up more than 200 miles of the Colorado River, including lower Cataract and all of Glen Canyon. Today, dramatically reduced reservoir levels have allowed the river to reclaim approximately 30 miles of its original channel in lower Cataract Canyon, although yearly fluctuations in river flow and reservoir volume mean that those 30 miles are still somewhat of a transition zone between the two waterbodies.

Grand Canyon

Just upstream of the Glen Canyon Dam, the river (deep under Lake Powell) crosses the border into Arizona, the third state to claim a piece of its shoreline. Fifteen miles downstream of the dam is Lee’s Ferry, the starting point for Grand Canyon trips. This most famous piece of the Colorado River deserves its notoriety. For over 200 miles, the Colorado winds through one of the most magnificent canyons in the country. The walls of Grand Canyon encompass nearly 1.5 billion years of the earth’s history, and rise to 6,000 feet above the river at their highest point. River trips often take over 2 weeks to run the length of the canyon, and non-commercial boaters may wait years to score a permit to run their own trip. The rapids are big, fun, and plentiful, although the water that is released from the dam is a brain-freezing 46 degrees Fahrenheit; even in the hottest part of the summer, splash gear is a necessity. Most trips take out at Diamond Creek, 226 miles downstream from Lee’s Ferry. The canyon continues for another 50 miles before ending dramatically at the Grand Wash Cliffs, although the water becomes increasingly sluggish as Lake Mead swallows the river’s current. Here, as in Cataract Canyon, the transition between river and reservoir changes yearly, but in most years, due to ongoing drought, the river seems to be winning.

Black Canyon

The iconic Hoover Dam, the first to be constructed on the Colorado River, is situated squarely at the head of Black Canyon. The last section of the river that is truly accessible to non-motorized craft, Black Canyon is a 30-mile stretch of beaches, secret coves, and hot springs that was designated as a National Water Trail in 2014. There are no rapids to speak of, and because the water slows as it approaches Lake Mohave (another reservoir), this section is better suited to kayaks and canoes than rafts.

The End of the Colorado River

Through Black Canyon and beyond, the Colorado River defines the border between Arizona and Nevada, and then Arizona and California. This is the beginning of the end for the river. Of the 17-plus dams and diversions on the river, eight of them are in the 280 (or so) miles between Hoover Dam and the Mexican border. The river begins to resemble more of an industrial canal than a natural waterway, running quietly downhill in brief spurts between impoundments.

The Black Canyon National Water Trail ends in Lake Mohave, which is created by the Davis Dam. Davis was built in 1960 in order to store water for delivery to Mexico, per the stipulations of a 1944 treaty. Prior to this treaty, the United States had conveniently ignored the fact that the Colorado River flowed into Mexico and, therefore, that Mexico deserved a share of the river’s water, too. The 1944 treaty declared that Mexico is entitled to 1.5 million acre-feet of Colorado River water per year.

After Davis Dam, there is Lake Havasu, created by the Parker Dam. Below Parker Dam, there’s the Parker Strip, a 16-mile stretch of “river” lined with palm trees and RV parks, popular for motorboats, jetskis, canoes, and tubing. The Headgate Rock Dam provides water for farms on the Colorado River Indian Reservation. The Palo Verde Diversion Dam sends water to citrus farms in Imperial and Riverside Counties, California. Senator Wash Dam was constructed to aid with the scheduling of water deliveries downstream, and it allows for extra holding capacity in times when there is less demand for water. The Imperial Diversion Dam was built around the same time as the Hoover Dam. This is the diversion that allows California’s Imperial Valley to be one of the most productive farming regions in the United States. The Laguna Dam diverts water to Arizona’s Yuma District, and finally, the Morelos Dam, which straddles the U.S.-Mexico border, diverts Mexico’s share of the Colorado River to the highly developed agricultural lands in the Mexicali Valley (Source).

Historically, the Colorado River ran through Mexico for another 100 miles or so, spreading across the flat topography, myriad channels creeping through a jungle of lush riparian growth. The delta was its own wetland ecosystem, home to jaguars, dolphins, and countless bird species. But because of the demand for the river’s water, the delta has been dry for decades. The Colorado River no longer reaches the Gulf of California. Instead, its journey ends in the ditches, pipes, and sprinkler heads of the Mexicali Valley.

Colorado River Rafting: The Ultimate Way to Experience a National Treasure.

The Colorado River offers boaters and adventurers an incredible variety of landscapes to explore: steep mountain ravines, grassy meadows, brilliant red-rock canyons, wide-open desert expanses, and mysterious black-walled gorges. It is also the key component of an enormous, highly engineered plumbing system. The river provides drinking water to approximately 40 million people in hundreds of western towns and cities, including several that aren’t even within the Colorado River basin, such as Denver, Salt Lake City, Phoenix, Los Angeles, and San Diego. The modern Colorado River is a complicated entity, but rafting it is simple. Whether you choose to do a day trip through Gore or Glenwood Canyon or a multi-day trip in Cataract or Grand Canyon, rafting is the best way to gain a personal understanding of this beautiful, critical, multifaceted waterway. Dip your toes in its currents. Stretch out on its sandy beaches. Ride its rapids. Look up, look around, and breathe deep. You may never be quite the same again.

Susan Munroe is a reader, writer, traveler, and river guide. She moved to Utah from New Hampshire for the mountains, but it was the allure of the desert and its rivers that have truly kept her transfixed. More than eight years after she first came to work for Holiday River Expeditions, she still can’t get enough of life on the water. Susan spends her winters skiing and working in Salt Lake City, Utah, with frequent trips to southern Chile to run the Río Baker and support the work of the educational kayaking exchange program Ríos to Rivers. See more of  Susan’s work here: www.susanmunroe.com