A mudslide snaked down from Royer Gulch the east end of Telluride and into the East Pandora neighborhood Tuesday afternoon. The mudslide left three feet of debris on the river trail by Pandora Lane and additional “weather-related impacts on roadways and passes,” according to San Miguel County Sheriff’s Public Information Officer Susan Lilly.
There were no reported structural damage or injuries, she added, but one hiker, who “requested assistance getting out of steep terrain that was compromised with the torrential rain and slides” was safely retrieved by way of UTV up Tomboy Road.
Telluride deputies and search and rescue also responded to a motorist, who explained that he was “stuck above the stairs on Black Bear Pass” with other four occupants and his pet, Lilly said. No injuries were reported during either rescue.
“On top of everything, we have people who choose to drive on dangerous passes with little or no experience, and are ill-equipped for weather-related emergencies,” Sheriff Bill Masters said in a social media post Tuesday evening.
There was also a “suggested and voluntary evacuation of a family in a home on Pandora Lane where the mud, debris and water were particularly impactful,” Lilly explained. “We encourage emergency awareness and preparedness for all residents and visitors to our county. The county has thorough emergency plans and protocols, as well as preparedness tips all available on the county website. All of the county agencies train for many types of emergencies, but at the end of the day it is each individual’s responsibility to be prepared to act in case of emergency. We encourage everyone to sign up for CodeRed (public.coderedweb.com) and follow us (San Miguel County Sheriff) on Facebook for important safety alerts.”
A flash flood watch was in effect for Telluride Wednesday.
The forecasted weather “could produce similar flooding problems experienced yesterday," according to a San Miguel County Sheriff Facebook post Wednesday.
Lilly added that the forecasted monsoonal flow for the next week has not occurred in the past three years. As of press time Wednesday, Black Bear Pass has reopened, but people were discouraged from traveling in the area. Imogene Pass was closed to allow the county to check on bridge safety. Pandora Lane was open to residents only. Highway 145 east of Lone Tree Cemetery was open to alternating lanes due to debris removal. Travel to Bridal Veil was also discouraged.
“Conditions during particularly sudden, heavy rain or monsoons are favorable for slides like what we experienced Tuesday,” Lilly said. “It’s difficult to ‘predict’ slides, however, as opposed to forecasting or predicting other weather-related events. Mudslides can be caused by acute events such as an earthquake. In our case, mudslides are typically caused by heavy rain that accumulates quickly on the ground and loosens dirt and rocks creating a mudslide.”
The Telluride Science Research Center canceled their Town Talk due to “travel danger and mudslide potential,” development director Mark Kozak said in a news release Tuesday. He added the calculated risk for panel participants driving in from outside of town was too high.
Mike Charnick, a National Weather Service (NWS) meteorologist based in Grand Junction, explained that mudslides are a “common threat” in San Miguel County during the summer due to “the influence of the North American Monsoon.”
Mudslides are a result of “ample moisture” combined with “several days of rain,” leading to saturated soil, Charnick said. “It is possible to predict the threat or likelihood of mudslides occurring if antecedent conditions are favorable (well-saturated soils and the potential for additional heavy rain) six to 12 hours out,” Charnick said. “However, our ability to forecast the exact location of a mudslide occurring is considerably more difficult. It all hinges on where showers and thunderstorms develop and how they track over a particular area. Our time scale is usually on the magnitude of 30 minutes to an hour.”
Many mudslides occur in areas of previous wildfires, since vegetation hasn’t “regenerated” and the soil isn’t able to absorb rainfall, according to Colorado Department of Transportation (CDOT) Communications Manager Michelle Peulen. She added that it is important for motorists and hikers to “know before you go,” urging people to sign up for the travel alerts on CDOT’s website and the NWS forecast.
Charnick added that the role of the NWS is to prepare the public and their partners, which include local law enforcement agencies, when mudslides have occurred. NWS hosts spotter talks and workshops several times a year to teach people how to identify hazardous weather features and report perilous conditions, Charnick said.
“In order to better be prepared for mudslides, people should monitor the latest forecast before heading out for the day by visiting our website at weather.gov/gjt, particularly during the summer months,” he added.