Rainbow Arch, located just above the visitor center in Arches National Park, collapsed sometime this winter. A park ranger noticed it was no longer standing during a hike in February. The arch was cataloged by Stevens and McCarrick as SA-137 and had a reported span of 11.7 feet.
A research team from the University of Utah, including Jeff Moore and Paul Geimer, had actually been studying this arch not long before the collapse. The “before collapse” photos here were taken by Jeff Moore, and the “after collapse” photos were taken by Paul Geimer. The “before-after” comparison below was assembled by Holly Walker.
The team made vibration measurements four times at the site in 2017, focusing on a prominent crack working through the center of the span that appeared to be putting the structure in jeopardy. The crack is circled in the photo below.
Close-up photo of the crack before collapse:
However, the team observed no changes in the crack or vibration characteristics over 12 months, and backed off on their monitoring program, believing the arch to be more stable that it appeared.
The collapse is bittersweet for the team, as it highlights and validates the fragility of these features, but unfortunately they were unable to record its last few weeks and months and identify accumulating damage.
Below is a photo after collapse.
While they can’t say for certain what caused the collapse, they believe the most likely explanation is that fatigue caused by daily and annual heating cycles finally stressed the tip of the crack enough to cause a runaway failure sometime this past winter.
Rainbow Arch lives on in the virtual world as an interactive 3D model made by the research team that can be found at https://skfb.ly/VMvB.
Rope swinging at Corona Arch is now a thing of the past (photo courtesy Brian Mosbaugh at Slacklinemedia.com, Instagram: @Moabmonkeys).
BLM public information officer Lisa Bryant has supplied NABS with the following statement:
BLM-Moab has restricted roped activities, including swinging, for about 37 acres of BLM administered public lands, including Corona Arch (and nearby Bowtie Arch) and Gemini Bridges. The rest of the Moab Field Office area is still open for roped activities and includes several focus areas specifically for climbing and activities such as base jumping and highlining.
Gemini Bridges and Corona Arch are two outstanding geologic formations located northeast of Moab, Utah, in spectacularly scenic settings reached by short hiking trails. Corona Arch was acquired May 8, 2014 through the Utah Recreational Land Exchange, although the hiking trail leading to the arch has always crossed BLM managed lands.
Both features have been very popular destinations for hikers, sightseers and photographers for many years. It is estimated that 40,000 people visit Corona Arch and 50,000 people visit Gemini Bridges each year. Both geological features, but especially Corona Arch, are among the most often photographed sites on BLM lands.
In recent years Gemini Bridges and Corona Arch have become popular areas for a small number of visitors engaging in roped activities, such as highlining and swinging. This had led to a number of complaints from the public about the roped activities diminishing the experience of hikers and sightseers. Recently damage to the arch has also been noted from the rigging structures and ropes. On January 6, 2016 BLM issued a decision to temporarily restrict roped activities for two years, while it looked at appropriate management for the area. Following several public comment periods and environmental reviews, and the federal rule making process, that restriction became permanent on August 17, 2017.
Dave Kennedy, member of the Natural Arch and Bridge Society Board of Directors and former editor of its newsletter, SPAN, wrote this article about his trip to Rainbow Bridge for the publication Our Backyard in Glade Park, Colorado, September 6, 2017.
Lake Powell attracts a couple of million visitors to its blue waters and scenic red sandstone surroundings every year and about 100,000 of them make the trip to see Rainbow Bridge. This natural rock span, listed on Google Earth as the world’s largest natural bridge, though it is not, sits in Utah in a branch of Forbidding Canyon about 50 miles up-lake from Glen Canyon Dam.
The Natural Arch and Bridge Society has a page on their website at naturalarches.org which lists the “Big 19” arches and bridges in the world known to have a span greater than 200 feet. The Society seems to be the only body to set a protocol for measuring arches, which gets to be very technical for lay people. In short, span is defined by NABS as the horizontal extent of unsupported rock and is the organization’s basis for ranking the world’s arches and bridges. The Big 19 shows that Rainbow Bridge, spanning 234 feet, is the 6th longest natural bridge in the world and the 11th longest arch in the world (all natural bridges are arches, but not all natural arches are bridges). Its height is listed at 245 feet, making it also one of the tallest natural arches in the world. The five longest natural bridges listed in the Big 19 are all located in China. Of the Big 19, nine are located in China, nine on the Colorado Plateau and one is in the Sahara Desert of northeastern Chad, Africa.
In the NABS nomenclature, Rainbow Bridge is classified as a meander bridge formed in Navajo sandstone. That geologic stratum dates to the Jurassic Period from about 145 million years ago to about 200 million years ago. The bridge soars in a huge arc over the canyon and its intermittent stream below. The reaches of Bridge Canyon stand sentinel behind it and the entire scene is watched over by 10,000’ Navajo Mountain in the background. This is an outstanding example of the fabulous and fascinating landscapes of the American southwest.
President William Taft designated 160 acres that includes Rainbow Bridge as a National Monument in May 1910, less than a year after it was first documented by Anglos, though it could have been seen earlier by explorers who didn’t bother to record their having seen it. There is evidence of Native American habitation and visitation that dates to ancestral puebloan times and the bridge is held sacred by Navajos, Paiutes and today’s pueblo cultures. The native name for the bridge translates to “rainbow turned to stone.”
The native religious reverence for Rainbow Bridge has generated controversy over the years, which has been resolved to no one’s complete satisfaction by the placement of boulders and signs to discourage visitors from approaching or walking under the bridge. The National Park Service asks visitors to respect the site’s traditional religious nature by not doing so, but a lawsuit in prior years established that the NPS may not ban people from going under the bridge and that the current voluntary request does not constitute a ban.
Another controversy surrounding Rainbow Bridge comes from the story of its Anglo discovery. Two parties had been trying for a few years to locate the bridge based on tales told by Native Americans. One was led by Byron Cummings, a dean at the University of Utah and another by John Wetherill, he of the famous Wetherills that discovered Mesa Verde. At length the two parties combined for the trip that led to the finding of the bridge in 1909. Heated arguments ensued as to whether the discoverer should be Cummings or Wetherill. At least one source lists them in an epic weasel-out as co-discoverers.
Other controversies involving this natural bridge include scientific values, access, protection and cultural significance, all of which have shifted over time and are probably still shifting today.
There are two official ways to get to Rainbow Bridge National Monument. You can take a boat or you can hoof it. Private boats are allowed to enter Forbidding Canyon and tie up at the courtesy dock at the trail head for the bridge. The dock has a restroom but no other services are to be had there. Commercial boats are run by the Glen Canyon National Recreation Area concessionaire from Wahweap Marina. Trips take all day and, at the time we went, cost $125 per person.
The distance of walk from the dock to Rainbow Bridge depends on the level of Lake Powell. When we went the walk was about 1.25 miles each way. The trail ends at a viewing area near the bridge and there are signs requesting that visitors respect traditional religions and do not approach or walk under it. The concessionaire staffer on our trip yelled at one tourist to return to the viewing area and not go farther.
The boat ride is about two hours each way and leaves Wahweap Bay on the way to skirting Antelope Island on the 50-mile trip up-lake. Warm Creek Bay and Padre Bay, Lake Powell’s largest bay, offer up their fantastic scenery along the way.
The tour travels by several good viewpoints of Tower Butte which was a landmark for travelers long before the reservoir came into being.
Observant passengers may see other small arches in the sandstone shoreline of the lake and photo opportunities abound.
Not long after the boat enters Forbidding Canyon, 25-foot Rainbow Canyon Jughandle arch comes into view high on the right.
The blue water contrasting with the sandstone canyon walls make the entire trip a photographer’s paradise. Online information about the tours and reservations can be found at lakepowell.com.
The other official way to get to Rainbow Bridge is to hike from Navajo Mountain by way of either of two long trails. The northern route is 32.7 miles roundtrip and involves about 7000 feet of elevation change. It has the advantage of being less steep, though harder to get to, and it also goes near lovely Owl Bridge. Its 61-foot span will have you digging your camera out of your backpack.
The southern trail from Navajo Mountain is shorter at 24.5 miles roundtrip but much steeper, with over 8400 feet of elevation change. Distances and elevations for both trails are taken from the alltrails.com website.
Both trails are entirely within the boundaries of the Navajo Nation except for the little distance they are in Rainbow Bridge National Monument. As such, permits from the Navajo are required and can be obtained from the Navajo Nation Parks and Recreation Department in Window Rock, Arizona (928-871-6647) or from their website at navajonationparks.org.
Hikers with shuttle capabilities could walk in on one trail and back the other, and by making prior arrangements with the concessionaire at Wahweap Marina, hikers can ride out on one of the boat tours to the marina.
The trails are not maintained and may be subject to flash flooding, hot, dry conditions in the summer and severe cold and wind in the winter. There are not many trail signs but the trails are mostly marked with small stone cairns. These routes are not recommended for inexperienced or casual hikers.
The Lake Powell area of Utah and Arizona envelops a treasure trove of nature’s wonders for visitors of all interest levels from the casual to the intrepid. Visiting Rainbow Bridge will surely be one of the highlights of anyone’s trip to the area.
The Natural Arch and Bridge Society Spring 2015 Arch Rally was held in Escalante, Utah, and had about 40 members in attendance. It was great fun with several trips daily. Here are some photos from the Rally (hover for caption; click for slide show).
Your webmaster and Blog editor David Brandt-Erichsen got a new job as Natural Arch Consultant when NABS was asked by Red Bull Adventure for assistance in compiling a collection of arch photos. Although it was one-time only and there was no pay, it’s a start!
The NABS Board and a few other members joined in on the fun of making suggestions, and two of our intrepid international arch hunters, Ray Millar and Gunter Welz, actually got paid for some photos.
The Red Bull editors of course made the final selection. The article was published July 28:
Merwin Canyon Arch is on BLM land in Kane County, Utah, east of Zion National Park. Merwin Canyon is a side canyon of Bay Bill Canyon which itself is a side canyon of Parunuweap Canyon, the canyon of the east fork of the Virgin River. While the lower part of Merwin Canyon is just a sandy wash, 0.6 miles upcanyon it becomes a beautiful and easy to explore non-technical slot canyon. The arch is right at the entrance of the slot.
The opening has a width of approximately 40 feet and a height of approximately 25 feet. To take a better photo than mine, bring a tripod and a wide angle lens; take several photos with different exposures and then at home you can create an HDR photo on your computer.
Taking a GPS reading at the arch was not possible for me but it should be close to 12S 346250 4114530.
Directions: Less than a mile south of Mt. Carmel Junction turn west on a dirt road and drive on it about one mile to a fence with a cattle guard. Park there and walk down Parunuweap Canyon on a public road through private land for about 5 miles to the confluence with Bay Bill Canyon. If you have a 4 x 4 you can drive here if you don’t mind crossing the ankle deep river many times. Hike up the sandy wash of Bay Bill Canyon for 1 mile. Then turn left and walk up colorful Merwin Canyon for 0.6 miles to the arch and the slot.
These photos show a dramatic change in the appearance of Ring Arch in Courthouse Wash in Arches National Park. Sometime between April 29 and October 7, 2014, a significant portion of the arch collapsed, leaving the arch very much thinner and looking quite delicate.
As the photos show, the left abutment remains intact, but shortly beyond, a large amount of rock including a portion of the right abutment has fallen. The arc of rock that remains shows no fractures in the photos, but it showed no fractures in the earlier photos either. Standing under the arch, it appears as though much of the lower right front of the span has fallen.
Ring Arch may be seen almost directly west from the park road from a long pullout on the west side of the road (NABSQNO 12S-621729-4278463) about 0.15 miles southwest of the center of the Courthouse Wash Bridge. Binoculars will help, as the arch is about 1.3 miles from the road and the arch location is not obvious.
There is no established trail to Ring Arch. Walking directly to it from the park road view is not recommended since it is difficult to avoid disturbing sensitive desert soils. It’s also unpleasant to deal with the stickers in dense patches of Russian thistle and several tumbleweed-filled drainages. A better route starts on a use trail at the parking area on the northwest side of Courthouse Wash (12-622006- 4278791).
Ring Arch is tucked in a northeastward facing alcove and has morning sun. Courthouse Wash can have standing water, serious mud, and voracious seasonal biting insects. Walks taken after a dry spell and when insect populations are low are recommended. If you are good at finding use trails and return the way you came, your round-trip walk will be about 4.0 miles. This is a wonderfully pristine area, so stay in drainages when possible and do your best to insure there is only one narrow footpath leading to the arch.
Ring Arch is a very old pothole type natural arch, which has formed in the Slick Rock Member of Entrada Sandstone. The Slick Rock Member was deposited in tidal mudflats, beaches, and sand dunes during the Middle Jurassic period between 180 and 140 million years ago.
Sources agree that Harry Reed, a Moab photographer and custodian of what was then Arches National Monument, first reported Ring Arch in 1940. Slim Mabery, a former district ranger at the monument, named the arch in 1961. The name comes from the shape of the arch. According to the World Arch Database, Ring Arch’s span is 45’ with a height of 39’. After the recent rockfall, the arch may be marginally taller.