Officials at Glen Canyon National Recreation Area are now requiring personal flotation devices to be worn by those using hand-propelled watercraft on the stretch of Colorado River between Glen Canyon Dam and Lees Ferry.
The 16-mile section is increasingly popular for paddleboarding, canoeing and kayaking.
Officials say conditions can quickly change on the river and water temperatures are often around 50 degrees Fahrenheit making it difficult to reboard watercraft or swim to shore after being immersed in water.
In addition, boat traffic can often be congested in narrow canyons.
The Park Service says all users must use a U.S.-Coast Guard-approved PFD while on the river and the new requirement is meant to increase visitor safety.