San Juan - 01. Sand Island to Mexican Hat

San Juan, Utah, US


01. Sand Island to Mexican Hat (Upper San Juan)

Usual Difficulty II (for normal flows)
Length 26.5 Miles

San Juan Canyon

San Juan Canyon
Photo by Thomas O'Keefe © taken 04/13/14 @ 800 cfs

Gauge Information

Name Range Difficulty Updated Level
usgs-09379500 500 - 8000 cfs II 14d11h22m 2990 cfs (running)

River Description

The San Juan River is a great multi-day river trip and this section features one of the finest collections of petroglyphs in the southwest. This section is often run as a three day trip but can also be the start of a longer trip that continues on downstream past Mexican Hat to Clay Hills Crossing.
The put-in is at Sand Hills Crossing near Bluff, Utah approximately half a mile upstream of the Highway 191 Bridge. Sand Island has a ranger station, several campsites including group sites, drinking water, toilets, trash collection, and a wide boat ramp that provides enough space for a few trips to stage simultaneously.
The run begins in open desert country. The first six miles have several petroglyphs and moki steps carved in the sandstone as toeholds for Native Americans who traveled through these canyons in centuries past. Particularly impressive panels with an incredible density of petroglyphs are visible just upstream and downstream of Butler Wash. A short hike up the wash takes you to some smaller ruins and petroglyphs.
Six miles into the trip you reach the pullout for Riverhouse. It is about a 1/4 mile hike from the river to the base of the cliff. This ancestral puebloan ruin from the thirteenth century is built in a sandstone alcove overlooking the river. With 14 rooms this is the largest ruin along the river. It is visited by river runners and those on jeep tours. Given the heavy visitation, it is important to stay off the walls and out of the rooms so the structure remains undamaged for the benefit of future visitors. Less than a mile downstream of the Riverhouse is Barton's Trading Post. An interpretive sign marks the site which was established in the 1880s. The old trading post is at the base of San Juan Hill which was one of the last natural barriers encountered by Mormon pioneers who were searching for a route from Escalante to Bluff. Over the winter of 1879-1880, the pioneers sought to establish a settlement in the region to the east of the Colorado River and the journey that was expected to take only six weeks instead took six months. This last geologic barrier is a north to south-trending monocline known as Comb Ridge that extends approximately 80 miles and is bisected by the San Juan River. A short hike up San Juan Hill offers an impressive panorama of the landscape. All of these geologic and historic sites can be easily visited from one of the river camps on river right between River House and Comb Wash.
As you continue downstream, the river cuts through Comb Ridge as you approach the entrance to the canyon. On river left you will pass the trail to the Mule's Ear Diatreme. This feature is a volcanic pipe that formed when magma, originating in the upper mantle, rose up through a crack in the earth's crust. It takes a couple hours to hike up and back but it is easy walking on the sandstone ridge to reach the diatreme.
The next approximately 10 miles of river are through a deep canyon. A couple easier rapids get you ready for Four Foot Rapid, the first of the class II drops which can be scouted from the right. Below this rapid you pass the Perched Meander and Midway Canyon on river right. Both of these are great hikes accsessible from Midway Camp. The Perched Meander is a relatively easy hike where you can hike the ancient river channel before erosion sliced through the neck of the meander. Midway Canyon is a more technical hike with a series of puzzles that must be solved to pass upstream of the big ledges you encounter on your way up.
Another few miles downstream you will encounter Eight-Foot Rapid which is the most technical rapid on this section. Technical manuvering between a large midstream boulder at the top of the rapid and a bedrock wall on the right is required to safely negotiate this rapid. This drop is easy to scout from river left.
While there are two camps immediately below Eight-Foot Rapid, the next two miles of river are closed to camping as this is prime habitat for bighorn sheep who need to be able to access the river for water without being disturbed. The end of this section is marked by Ledge Rapid which is formed by a debris fan on river left that pinches the river against the bedrock wall on river right. You will want to run river right to stay in the main current and clear of the rocky shoals but keep your boat angled to the left to avoid going up against the wall on river right. The drop can be easily scouted from the top on river right.
Within a mile of Ledge Rapid the canyon starts to open up and you pass Fossil Camp on the right. As its name suggests, this is a fun place to view fossils. Within a few more bends the Mexican Hat Rock comes into a view on river right. Once you pass this feature it is only another couple miles down to the boat ramp at the BLM River Access site of Mexican Hat. You will find camping, garbage collection, and toilets at this site but no running water.

Permit Information

A permit is required year-round to float any section of the San Juan River between Montezuma Creek and Clay Hills. Permits are issued only through a pre-season lottery (for high use season of April 15 - Jul 15) and advance telephone reservations (for low and moderate use season to individuals 18 and older.

StreamTeam Status: Not Verified
Last Updated: 2018-12-02 18:36:12


Rapid Summary

Mile Rapid Name Class Features (Legend)
11.7Four Foot RapidIIPhoto
17.2Eight-Foot RapidIIPhoto
19.3Ledge RapidIIPhoto

Rapid Descriptions

Four Foot Rapid (Class II, Mile 11.7)

Four-Foot Rapid

Four-Foot Rapid
Photo by Thomas O'Keefe © taken 04/13/14 @ 800 cfs

A class II read and run or scout from river right.

Eight-Foot Rapid (Class II, Mile 17.2)

Eight Foot Rapid

Eight Foot Rapid
Photo of Tracy and Jan Tackett by Thomas O'Keefe © taken 04/13/14 @ 800 cfs

Run right of the big rock at the start and then move back to the center to finish the rapid.

Ledge Rapid (Class II, Mile 19.3)

Ledge Rapid, Upstream View

Ledge Rapid, Upstream View
Photo of Web Pierce and Dave Boyer by Thomas O'Keefe © taken 04/13/14 @ 800 cfs

Run to the right to stay in the main current and avoid the rocks on the left but be aware of the wall on river right.

User Comments

Users can submit comments.
April 21 2008 (3928 days ago)
x (1)
We ran this section at around 4,500 cfs. For fully-loaded open canoes, there are class II sneak
routes, but the center wave trains and holes for the larger rapids, e.g., 8 ft., would be class

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