Mudslide area monitored
Evacuation plans are ready if needed.
Mesa County authorities announced Friday afternoon that the initial water surge has passed and the site of the massive West Salt Creek landslide near Collbran is stabilizing as water continues to flow at a slower rate.
The county said Friday it has initiated a Level Two response to its emergency preparedness action plan, advising residents in the area to be prepared to evacuate. Officials will keep that alert and will monitor the situation throughout the weekend.
A pond at the landslide area released water and cut a new drainage channel Thursday evening.
“Mesa County Sheriff deputies are contacting people who live nearby in addition to reverse 911 notifications,” the county said in a news release. “Road and Bridge equipment is being staged in Collbran as well as thousands of sand bags in the event flooding becomes an issue.”
The 2.8-mile-long West Salt Creek landslide on the Grand Mesa on May 25, 2014, was the longest such slide in Colorado history. It killed three men.
Worries of another catastrophe have persisted in the slide’s wake, particularly last spring, when heavy rains prompted warnings. The main risk, officials say, is in early spring as snowmelt travels down the slide area.
Water that has collected in a depression near the top of the slide has created a “sag pond,” which continues to spark fears among geologists of another catastrophe.
In October 2015, the Colorado Geological Survey said conditions remain at the West Salt Creek area that could prompt another disaster of comparable magnitude.
The highest alert level for the landslide area is Level Three.
“The alert level was raised because the pond spilled over the slump block at the head of West Salt Creek early (Friday) morning,” said Jeffrey Coe, a research geologist with the U.S. Geological Survey who has studied the slide. “There was some local flooding near the toe of the landslide. A flood watch was issued for areas downstream. But from everything I have heard so far, the impact to downstream areas has been minimal.”
Coe’s research showed the initial deadly slide was caused by a rainstorm over melting snowpack in the area, triggering a series of events that led to the disaster.
The county said Friday that an initial water surge made it through Collbran without overflowing the banks of Plateau Creek. There have been no signs of land movement.
“Right now, the landslide is doing what we want and expect it to do,” the county said. “However, if Mother Nature decides to take more land down, we want residents to be ready to evacuate.”
Officials say they have a team flying over the area that will monitor the conditions.