Arizona. Rounded Billows of Sandstone: A Journey through the Colorado River’s Horseshoe Bend
The Colorado River is the principal source of water for more than 40 million people. Beginning in the Rocky Mountains near La Poudre Pass, Colorado and extending over a course of 2,300 kilometers, the river drains an area that includes parts of seven U.S. and two Mexico states. Its name is derived from the Spanish word for red water. In part because of its high sediment load, early settlers described it as “too thick to drink, too thin to plow.” The river was not well known in 1846 when much of its watershed was incorporated into the U.S. Charged with investigating the river’s geography, geology, and ethnographic history, Major John Wesley Powell led an expedition down the length of the river in 1869. Recording his impression, Powell noted, “Past these towering monuments, past rounded billows of orange sandstone, past these oak-set glens, past these fern-decked alcoves, past these mural caves, we slide hour after hour, stopping now and then, as our attention is arrested by some new wonder.” Today, the river’s course is impeded by several massive dams. Moving southwest through Utah, it enters Lake Powell just north of Page, Arizona.
Measuring 220 meters in height, Glen Canyon Dam was constructed using an arch-gravity design similar to nearby Hoover Dam. Completed in 1966, the dam and reservoir provide flood control and storage for irrigation and domestic water uses. Because of Lake Powell’s considerable volume, the dam is also used to generate hydroelectric power. Water releases from Glen Canyon Dam follow a prearranged schedule with 227 cubic meters per second flowing from the dam between 7:00am and 7:00pm and 142 cubic meters per second between 7:00pm and 7:00am. In stark contrast to the muddy and turbid water that flowed before the reservoir’s construction, water emerging from the dam is relatively clear and sediment-free. Just downstream is Glen Canyon Dam Bridge. Anchored to sheer sandstone walls on each side of the river, the bridge is 387 meters long and 210 meters above the river. When completed in 1959, it was the tallest arch bridge in the U.S.
Departing southwest from Page on US Highway 89, we turned west, passing a kiosk where we paid an entrance/parking fee. The parking lot and trail are maintained by the City of Page. We followed the 2.4-kilometer (round trip) trail to an overlook 300 meters above the river. Below this place the river makes a gentle 270° turn forming a massive loop with sandstone cliffs surrounding emerald-green water. The river is flanked by sandbars and vegetation. Horseshoe Bend was relatively obscure until 2009 when it was featured as the default screensaver for the Microsoft Windows 7 operating system. Today, about two million people visit the overlook each year. Geologically speaking, the massive curve is a 305-meter-deep entrenched meander. The story of its formation began five million years ago when the Colorado Plateau experienced a period of uplift (the cause of which remains unknown). Subsequently, meandering rivers crossing the area became trapped in their incised beds leading to extreme down-cutting. At some point in the future the river will carve out a shortcut, forming a natural bridge at the point where its two channels push close together.
Our second sojourn involved traveling by boat through a section of the river. We arranged for our tour a few weeks in advance. After parking at the tour company office in Page we were given a 30-minute orientation. Subsequently, we boarded a bus for Lee’s Ferry where we met our guide. Lee’s Ferry was an important crossing point for early explorers and settlers. It is the only place within hundreds of miles where it’s possible to access the river from both sides. John Doyle Lee began running a ferry service there in the mid-1800s and continued transporting people and goods for 55 years until a bridge was constructed. Today, Lee’s Ferry is used as a launching point for fishing trips and whitewater rafting excursions through the Grand Canyon.
Our guide assisted our group as we boarded a shallow-draft inflatable boat equipped with a single large outboard motor. The boat was arranged with long benches along each side of the hull and in the center. A console in the center-aft section contained the steering wheel and throttle. Our guide explained that passengers sitting near the boat’s bow were likely to get wet from spray. Hoping to be seated in a good place for photographs, my companion and I volunteered for the most forward seating positions, a decision we soon regretted. Departing upstream, we passed through Echo Canyon, five kilometers north of Lee’s Ferry. Although it was early fall, steep canyon walls surrounding the river channel prevented the sun from reaching our location and within ten minutes we were soaked from spray coming over the bow. Wet and cold, we sheepishly moved to empty center bench seats near the aft of the boat.
Continuing upstream, we reached Waterholes Canyon a popular alternative for visitors wishing to hike through a slot canyon. Like nearby Antelope Canyon, visitors to Waterholes Canyon must have a permit and guide. The river appeared wider in straight sections and on the outside of curves, the water came into contact with the canyon’s steep sandstone sides. Elsewhere the riverbank has been colonized by an invasive plant called tamarisk (aka salt cedar). At the 14.5 kilometers mark upstream we reached Horseshoe Bend and its broad gooseneck curve. Near the top of the cliff, we could see visitors high above at the overlook where we had been standing the previous day. We continued to Petroglyph Beach, located 16 kilometers upstream from Lee’s Ferry. After disembarking, we took a short hike through scrubby brush where our guide showed us ancient images carved into desert varnish that represent bighorn sheep, human figures, and birds. One of the most famous is “descending sheep,” a linear string of bighorn sheep images estimated to be 3,000 to 6,000 years old. In 2011, a North Carolina man was fined thousands of dollars for damaging ancient images at Petroglyph Beach. At the 21-kilometer mark from Lee’s Ferry we reached Honey Draw, our final upstream destination. On our return trip to Lee’s Ferry, we saw two desert bighorn (aka Glen Canyon bighorn) that have smaller bodies and lighter coats compared to bighorn found in the Rocky Mountains. We also saw a single feral horse grazing near a turn in the river. Although we didn’t see other animals, the area has populations of mountain lion, bobcat, black-tailed jackrabbit, coyote, and mule deer. The segment of river we were traveling on is also popular for fishing. Beginning in 2020, anglers have been offered US$25 for every brown trout caught between Glen Canyon Dam and the mouth of the Paria River. The incentive was put into place to address problems with non-native brown trout competing with native fish such as the endangered humpback club. On the return bus ride to Page, we passed Vermillion Cliffs National Monument. The 1,133 square kilometer monument protects Paria Canyon, Paria Plateau, Vermilion Cliffs, and Coyote Buttes.
