WYDOT to address Rupe Hill landslide

By Sarah Pridgeon
One of the largest landslides affecting a Wyoming state highway is located just outside Sundance on Hwy 14. A thousand feet in length and up to 70 feet in depth, it has been moving constantly since 2011, prompting the Wyoming Department of Transportation to initiate a project to replace that portion of the road before it fails entirely.
“We’re doing this now because of the potential that the road could fail, which would impact a greater area,” says Nick Hines, Environmental Coordinator. “We don’t want anybody getting hurt.”
The landslide is thought to be the result of flooding in the spring of 2011, caused by heavy rainfall and unprecedented snowpacks. It is similar to a landslide just ten miles east at Oudin Hill, which forced a road closure that same year.
“This project wasn’t something that was on our radar to go do,” comments Ronda Holwell, Public Relations.
“In 2011 we had huge wet slides and that entire portion slid and for us it’s not feasible to fix it in its current location. We’re reacting to what happened in 2011 and trying to mitigate and come up with a solution as quickly as possible.”
The environmental assessment for the Rupe Hill Project was presented at a public meeting on Tuesday. It includes a preferred option and alternative to replace the affected section of road.
The eventual aim is to ensure the long-term safety, maintenance and mobility of the road in the Rupe Hill vicinity. Though the landslide might remain stable for several years, Crook County is historically a landslide area and there is no way to know if and when it will fall.
“This is just the way the good Lord put it together, it’s just how it is. If it failed, we would have to close it. We’ve had landslides fall as far as 30 feet and there’s no way to negotiate with that,” says Stark.
“Things happen fast and it isn’t going to be pleasant. It could be very inconvenient and expensive for the public.”
The project has faced opposition from landowners in the vicinity, but has also met with encouragement from people who use the road.
“We even got a phone call asking why we weren’t doing anything to fix the road yet,” says Hines. “We said, well we are, but there’s a process.”
WYDOT has worked on the environmental study with the goal of minimizing impact on landowners and sensitive environmental resources and providing acceptable road grades, all with the minimum disruption to travel.
“The two things that came up in the environmental assessment were the location of wetlands and the location of archaeological sites,” says Tim Stark, Environmental Services Engineer. “We looked at wetlands and other things to avoid. Some cairns were identified so they can be avoided during the design stage.”
The preferred option will avoid the landslide area by building an entirely new section of road between mileposts 198.3 and 197.1, at a cost of $1.3 million. This alternative would avoid both direct and indirect impacts on archaeological resources and would have a relatively insignificant impact on visual resources, vegetation and wildlife habitat.
It was selected as the preferred option because it will affect fewer landowners, require 100,000 fewer cubic yards of fill material and cost significantly less. Based on geological testing, it will also place the new section of road on better soil conditions for the required embankments.
The route will change very little for motorists and, while visible to property owners, will not change the views of Warren Peak or Sundance Mountain. It will also improve travel and provide a reliable transportation route for goods, services, tourism and emergency services.
The alternative would create a new section of road between mile post 198.1 and 197.3 for a higher cost of $1.65 million and similar benefits, but greater potential adverse impacts. If neither is approved and WYDOT simply continues to maintain the road as it is, the landslide will continue to break apart.
“It does need to be put on a different alignment because the foundation of the existing alignment is moving, so it’s not a sound place to put it – it’s going to fall,” says Stark.
WYDOT anticipates that it will need to purchase new land and rights-of-way to address the need for a new alignment and has already involved the landowners who may be affected. The current comment period, however, is focused mainly on the environmental issues associated with the project, while the details of construction will follow later this year, such as lane numbers and widths.
“Design will commence after this process and that’s when all the nuts and bolts and the details will be worked out. We’ll know an exact date and an exact location, we’ll know exact fills and cuts of the road,” said Stark.
The official closing date for public comment on the environmental study is August 2 but WYDOT will continue to accept comments for a reasonable time afterwards. Right-of-way acquisition and design will begin in the fall and the project is expected to break ground in 2014.
Construction, if the preferred alternative is chosen, should not greatly affect travel on the road except when the new section is tied in with the existing one, which will be done as quickly and with as little disruption as possible.
The environmental assessment is available online at  www.dot.state.wy.us and at the Sundance Library. Comments can be directed to [email protected]
Through the design process we’ll be having public meetings as well, but we’d like people to take the opportunity to comment now. This isn’t going to be the last meeting, but don’t wait until it’s all sewn up already, get involved now,” says Stark.