There are numerous navigable (?) tributaries flowing into the San Juan River (navigability having to do with experience, training, equipment, river conditions and the company of other paddlers in your group, as well as local knowledge of the river and an emergency plan.) These above Navajo Dam include the Rio Blanco and the Navajo River, as well as the Piedra River and Los Pinos River which join the San Juan in Navajo Reservoir. Below Navajo Reservoir the San Juan is fed by tributaries that include the Animas River, La Plata River and Mancos River in New Mexico, and McElmo Creek in Utah, among many others. The San Juan tributaries originating in the San Juan Mountains are snowmelt streams with the normal highest flows between March and June, depending upon winter snowpack and spring rains. Southern tributaries generally are lower flow streams with much shorter seasons that may last from a few days to a few weeks, but which can flash carrying copious quantities of water rushing downstream during flash floods.

The San Juan River and its tributaries are to be taken very seriously. While not all rapids are major in characteristic the very nature of location is a hazard to life safety. Other than near Pagosa Springs the area is remote with little or no telecommunications due to the mountains surrounding the river, and the channel is choked with boulders. The East and West Forks may also be heavily congested with deadfall trees that mostly or completely block the channel. The water will be cold, so dress appropriately. And while the vast majority of the rapids on the San Juan will be Class II to III there are some definite Class IV's. Some of the tributaries to the San Juan have Class V or higher rapids, primarily due to the remoteness and difficulty of rescue in a stream choked with boulder and deadfallen trees making rescues even more difficult and dangerous for rescuers. Fortunately, you can scout most of the major rapids on the two forks and the river above Pagosa Springs from the road so that you will at least have a little info to consider before launching. But, aside from the difficulty of a very few rapids the San Juan in Colorado is a gorgeous, relatively easy trip for moderately experienced whitewater paddlers and probably something close to an E-ticket ride for those with less experience in whitewater, especially if they are paddling their own boat.