With just weeks left before temporary access roads open to the northern parts of Yellowstone National Park, attention is turning to permanent road replacements.
The new, temporary road between Gardiner and Mammoth is due to open to the public on Oct. 15. But the permanent road that replaces huge, washed-out sections of the old road is yet to be determined.
Engineers have been working since June to determine the best route for a permanent road.
“I asked for an analysis of every possible, constructible alignment down to Gardiner from Mammoth,” Park Superintendent Cam Sholly said.
What Sholly got was five alternatives. He says those will be analyzed in five ways.
The criteria include which will have the least environmental effect, which is the least visually disruptive, which is the fastest, which is the most cost-effective, and which is most resilient to future weather or seismic events.
That last item does not bode well for rebuilding the old route through the Gardiner Canyon.
During a tour of the road washout and the part of the canyon that collapsed, Sholly said: “When you think about going back through this canyon, and you look at this up here, like I said, you could potentially build it for, you know, you could build it to be resilient to a future flood event. But it might not be resilient to this whole cliff face collapsing on it. So it might be a really good opportunity to restore this river canyon back to its natural state.”
Sholly said there are good reasons to continue upgrading the temporary road to turn it into the new permanent route.
“We’ve put twenty million dollars into this Old Gardiner Road already and, you know, there’s no going back on that," he said. "I think a fundamental question we need to ask is, do we really want to blow out another two-lane in this park to Gardiner, right next to the two-lane we just created?”
Another consideration is the big cliffs looming over the old road.
“The last thing we want to do is build a viaduct through the canyon and have it imploded from up top. And I think there’s some real value to consider restoring that canyon to its natural state,” said Sholly.
Over in the northeast part of the park, Sholly said the new roads are already being built to withstand any future flood event and while the new road sections are called temporary, the work is permanent in nature.
He said an environmental assessment of future road work on the northeast road was already underway when the flood struck. Now the park may speed up improvements to any remaining vulnerable areas to match the work which has already been completed, he said.
Once plans for replacement roads are finalized, several alternatives will be presented to the public. Sholly said he expects it to take 3 to 5 years to complete work on the permanent roads.
Interview with Cam Sholly on YNP road repairs: