Search and rescue efforts continued in Grand Canyon National Park this week after a sudden raging flood over the weekend left at least two people dead and more than a dozen others unaccounted for, the National Park Service said.
As USA Today reports, water levels in the Grand Canyon’s Bright Angel Creek and Phantom Creek rose suddenly on Aug. 29 after a severe thunderstorm dumped more than 2 inches of rain in parts of the park, washing out footbridges and damaging part of the park’s water system. Additional rain was expected this week, the park service reported.
More than 60 people were evacuated, the park service said. The body of a 46-year-old man was later recovered near Crystal Rapids along the Colorado River, Grand Canyon National Park said in a 6:30 p.m. Aug. 30 update on the flooding.
It’s Monsoon Season in the Region
It’s the middle of the summer monsoon rainy season in the Four Corners area, where the corners of Arizona, New Mexico, Utah and Colorado meet, said Josh Weiss, a meteorologist with the National Weather Service Weather Prediction Center. The region typically receives a significant share of its rainfall during this time of year, Weiss said.
The Grand Canyon, along with other mountain canyons in places like Utah, are especially vulnerable to sudden flooding during the summer monsoon season. Dry, dense soil absorbs less water, while steep canyon walls and narrow channels quickly funnel rainfall into creeks.
The Grand Canyon flash flood shows how intense monsoon rainfall can overwhelm dry terrain within minutes, turning normally calm waterways into powerful currents, making them exceptionally risky places to be.
Drought and Dry Earth Added to the Flood Risk
Several factors caused the Grand Canyon flooding. Intense monsoon rainfall fell across dry terrain, while drought and the Dragon Bravo wildfire burn scar increased runoff. Together, these flash floods created dangerous flooding, forcing evacuations and widespread closures.
As rain falls on the dry, arid slopes in the region, large volumes of water can quickly flow into creeks and waterways. Burn scars on the landscape from those previous wildfires can also rapidly funnel water into dangerous downslope torrents. Post-fire landscapes can experience faster runoff because vegetation has been removed.
A map showcasing the Grand Canyon flood causes highlights how rainfall, drought, and the wildfire burn scar overlapped across the affected areas.
High pressure in the atmosphere over the region has been in a favorable position to pull in “a lot of moisture” out of the Pacific and Mexico in August, Weiss said. On top of that over the last two weeks of August, a trough over the eastern Pacific was bringing in even heavier rain than typical for multiple days in a row, Weiss said.
Intense rainfall remained the dominant factor among the flood causes, while drought and wildfire conditions added to the overall flooding risk.
Location of the Flash Flooding in Grand Canyon
Rain flowed into Bright Angel Creek and Phantom Creek, which flows into Bright Angel, where water levels rose rapidly according to U.S. Geological Survey gauges in the park. The gauge data are considered preliminary as the geological survey and weather service work to verify the totals and examine any potential equipment failures during the sudden onslaught of the water.
The Colorado River also rose briefly just upstream from where Bright Angel Creek empties into the river, in response to the sudden influx of water, according to the river gauge on the geologic survey, but quickly adjusted. The river is in severe drought, and water levels at two major reservoirs on the river recently reached record lows.
To put it in perspective, the average rainfall for the month of August is 2.67 inches. By August 29, only slightly more than 1 inch had been recorded at Bright Angel weather station. On August 29, 2.21 inches fell in a matter of hours, bringing the monthly rainfall total to 3.27 inches over less than a 24-hour period.
What parts of the Grand Canyon Remain Closed?
Flood damage to the Transcanyon Waterline prompted closures within the park, the park service posted on its website. Several areas in the park also are closed, as damage is assessed, and the park service encouraged visitors to check closures before arriving. Those include:
- Bright Angel Campground
- Phantom Ranch and Phantom Ranch Canteen
- The entire North Kaibab Trail from the trailhead to Phantom Ranch
- Black Bridge and Silver Bridge crossings on the Colorado River
- Colorado River closed to river traffic
- Overnight accommodations at the South Rim
No estimated reopening dates have been provided, the park said, also warning that other inner canyon closures may be necessary.
Park officials urged anyone who knows of hikers or backpackers who were in the inner canyon along the Bright Angel Creek corridor on Aug. 29, as well as anyone with a campground reservation in the affected area, to contact the park service at 888-653-0009. Or email.
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Photo Credit: Elisabeth Bender / Alamy.com
