Tough, Foot-Friendly Sandals Originating with Colorado River Guides: Chaco

Wearing sandals for outdoor adventures has become the norm, and they’re also popular for city use thanks to their comfort and style. Many brands are now offering a wide range of sandal types. But that leads us to wonder: "What exactly makes a truly good sandal?"

One brand we recommend is the Colorado-born sandal label Chaco. For this article, we interviewed Katsuaki Kono from A&F CORPORATION to dig deep into the roots and products of Chaco.

Building Sandals Tough Enough for Harsh Environments

"Chaco was founded in 1989 in Colorado, USA by Mark Paigen. As a river guide who often rafted and explored the Colorado River, he realized there were no sandals suited for life on the water. In search of hardwearing footwear able to withstand demanding conditions, he started developing his own. That’s the beginning of Chaco.

"Rafting can be enjoyed in many places in Japan as well, such as Saitama, Okutama, Gunma, Hakuba in Nagano, Niseko in Hokkaido, and even in Shikoku. There are courses for everyone, from beginners to those who want something a bit more challenging. The Colorado River is the same, featuring some seriously intense courses that weave between rocks and rush through rapids."

"Materials have improved in recent years, but back then, sandals made using ethylene-vinyl acetate, known as 'EVA,' wore out after about three years—the inner cushioning flattened, holes developed, and when the straps were attached with hook-and-loop fasteners, they lost strength and would sometimes come off and get whisked away in the rapids.

"I thought this was unacceptable, so I turned my attention to a material called high-density polyurethane. It offered excellent cushioning, shock absorption, impressive durability, and longevity. When making sandals for rafting, they must withstand splashed water and heavy stress of hundreds of kilograms. You’re not just riding in a boat—you might be jumping in, or sprinting along rocky shores to help customers. So sandals have to be truly tough and reliable.

"If your sandals get swept away in rapids, it can hinder rescue operations, and sharp objects like wood, nails, or glass can even pierce right through. That’s why it was necessary to create sandals with real grip, safety, and robust construction."

Classic Models: "Z/1" and "Z/2"

Let’s move on to the flagship models from Chaco. There are two main types: the open-toe "Z/1 Classic" and the "Z/2 Classic," which features a toe loop. Here’s a closer look at what makes these sandals unique.

"Chaco launched their brand with the 'Z/1' and later released the 'Z/2.' Both use the high-density polyurethane footbed described earlier and feature a one-piece continuous webbing strap as their signature design.

"With the desire to create sandals that are genuinely healthy for your feet, Chaco involved a German podiatrist in the development process, working together to refine the models with expert advice. This initiative eventually led to the creation of Chaco's original 'LUVSEAT' footbed (details coming up soon).

"The sandals deliver impressive grip on wet rocks and provide a secure fit that prevents them from slipping off, even in rough rapids. In over 35 years, the design of these sandals has hardly changed. Today, these two types remain recognized as the classic core of Chaco's lineup."

Spotlight on Chaco's Original LUVSEAT Footbed

Chaco sandals aren’t just tough—they also stand out as superior, healthy footwear. Let’s talk about their unique, originally designed footbed called LUVSEAT.

"As part of the brand’s distinctiveness, Chaco sandals are recognized by three key elements: the single-piece webbing, integrated footbed, and our uniquely developed LUVSEAT. Developed in collaboration with podiatrists, LUVSEAT supports the arch of the foot, while the U-shaped, concave heel cup fully cradles the heel.

"When it comes to walking comfort, the single-piece webbing I mentioned earlier can be freely adjusted, so it fits anyone—whether you have a high instep or wide feet. The ball of the big toe is the most prominent part under the base of your big toe, and by firmly securing this area with the webbing, your toes become easier to use.

"The support from LUVSEAT and the range of motion for your toes shifts your balance—if your pelvis tilts backwards, you’ll find your center of gravity moving forward, which encourages a more beautiful walking posture. Today, LUVSEAT is used in every Chaco product, and it has a proven positive effect on foot health. What’s more, Chaco sandals have earned the certification of the American Podiatric Medical Association (APMA)—a credential awarded only to products that pass rigorous podiatric scrutiny."

Pro Model Featuring a Vibram Sole

We’ve talked about the brand’s roots, staple products, and the LUVSEAT footbed. Now, finally, let’s introduce a model designed with input from professional river guides.

"Based on the classic 'Z/1' and 'Z/2' designs, we’ve released models equipped with the Vibram MEGAGRIP sole—trusted by professional river guides. The soles of Chaco sandals were originally specially designed to be slip-resistant and deliver excellent grip, even on wet rocks.

"For this pro model, we further pursued unmatched grip and durability for waterside adventures, developing an original Chaco outsole pattern in partnership with Vibram: the 'Vibram MEGAGRIP.'"

Chaco is also committed to repair and upkeep with a program called "ReChaco." Customers can ship their products to the U.S. headquarters, where sole or webbing strap replacements are handled. Here’s one memorable story: Some sandals sent in for repair in Japan are as old as 15 or even 20 years. That speaks volumes about the enduring durability of Chaco sandals.

Their safety and remarkable toughness make them a favorite with both river guides and backpackers. In Japan, they’re also widely worn for leisure—at camps, festivals, or day-to-day, and on rainy days thanks to their versatility. Chaco may well be a truly unique sandal, fusing exceptional toughness with proven support for foot health.