What You Need to Know About High-Water Rafting Trips in the West

For river guides and whitewater lovers, high-water rafting seasons in the western U.S. are responsible for many a tall-tale, told in celebration of big flips, upside-down boats, long swims and daring heroism.

Each winter, eager paddlers wait to see what Mother Nature has in store for the upcoming river season.  Hefty snowfall in the high elevations has the makings of an epic year and with each new snowstorm the excitement grows. But whether or not it will be a particularly memorable high-water season, and when, ultimately comes down to spring temperatures and snowmelt runoff across each region.

When is high-water season in the West?

On rivers across the West, the high-water window typically occurs from mid-May to mid-June with the possibility of lasting longer during years with above-average snowpacks.

“High water may last a few weeks in thin snowpack years, or prevail for a month or longer depending on how warm it is, how consistently warm it stays, and how cold it is getting in the high mountains at night,” according to Eric Riley, founder of the Swiftwater Safety Institute.

Since it all comes down to the elusive spring runoff, and the window is often short, some guides wait decades to experience their favorite rivers at record-setting high-water flows. For the average person, snagging a spot on a high-water rafting trip with a reputable outfitter is the opportunity for an unprecedented adventure.

What to Expect on the River

Prior rafting experience is not always necessary, but people considering a high-water rafting trip should be in good health, capable swimmers and physically fit. Some outfitters may also require a swim practice prior to certain trips when water levels are running higher than normal.

“Expect a faster paced trip that will require higher levels of muscular and cardiovascular exertion,” says Riley. “Expect to get wet, move fast, paddle hard and swim your butt off in the occasion that you find yourself in the water.” Being comfortable with your swimming ability is a must, he adds.

According to an article in Rafting Magazine by Commodore Trevor, long, cold swims are the biggest concern for high-water trips.

“Big snow packs mean that runoff will last well into the summer and the shock of cold water immersion can be debilitating even during hot summer trips,” writes Trevor. “Even if your safety boat is on point expecting long cold swims is the name of the game in big water boating.”

In addition to cold, fast-moving water and dangerous debris like trees and root balls, high-water conditions can create big hydraulic features, unpredictable crashing waves from unusual angles, strong eddylines, and boils.

“Wrap rocks turn into sticky holes hiding terminal surfs,” according to Trevor. “Trees and shrubs on the bank turn into hungry strainers hoping to gobble up unsuspecting swimmers.”

In preparation for commercially-run high-water trips, outfitters will often send their guides on multiple training trips as water flows increase to study the high-water lines and check for hazardous conditions like strainers, which can pin a swimmer and force them under water. Throughout the spring, they’ll also constantly monitor flows and weather forecasts so they can better anticipate which rivers will have high-water conditions.

Not for the faint of heart…

If you go on an early-season rafting trip, in addition to experienced guides who are familiar with high water, your trip may also be supported by safety kayakers, catarafts, or, on rivers like the Colorado River through Cataract Canyon, motorized snout rafts.  Since these boats are quicker and have more maneuverability, they provide an added layer of security in big water. And in the case of an unexpected flip, safety boats may be able to assist people who have come separated from their raft.

“Safety boats are commonly piloted by only one person, with one responsibility – to make sure your team has a stellar high-water experience,” says Riley.

Still, with fast-moving water and fewer eddies, safety boats can’t always reach swimmers immediately after a boat flips. So if the idea of going for a cold and lengthy involuntary swim or self-rescuing (aggressively swimming to a nearby raft or shore) makes you nervous, then a high-water rafting trip might not be a good fit. Families and people looking for a fun, but more leisurely pace should consider planning rafting trips during July through September when river flows have typically returned to normal levels.

How to Prepare for a High-Water Rafting Trip

There are inherent risks in river rafting, and even if you go with highly-trained and experienced guides, you are ultimately responsible for your own safety. Being prepared for the various situations that could arise on the river and dressing for early season rafting conditions are of utmost importance.

For the highly adventurous, though, there’s nothing quite like high water. To experience Utah’s Cataract Canyon, which offers up some of the biggest commercially-run rapids in North America during record-setting years, is incomparable. To paddle the Wild & Scenic Tuolumne River in California or Idaho’s Salmon River at high flows is nothing short of epic. These rivers – to name just a few with notorious high-water reputations – are true bucket-list adventures.