GLIDE — Three members of a five-man crew felled trees perched precariously close to the edge of an unstable hillside above Little River Road Wednesday.
It’s a section of roadway that has repeatedly been blocked by rock slides over the past seven years.
On Wednesday, the crew was clearing vegetation in preparation for a construction project the county hopes will be a permanent fix for the problem.
It’s a project that’s long been in the works, but the almost $5.2 million price tag was more than Douglas County could afford until it was awarded a Federal Lands Access Program grant that will pay $4.6 million of the cost.
Little River Road branches off Highway 138 East just west of Glide and winds its way along Little River, which looks more and more like a creek the further upstream motorists followed it on a dry day in August.
The road passes Peel Country Store and Wolf Creek Job Corps. Eventually, it reaches popular campgrounds and waterfall hikes in the Umpqua National Forest.
Just past milepost 24, the road narrows to a single lane where rock sprawls across one lane of the road. The hill there will soon receive a facelift that includes inserting metal bolts into the rock and stretching a heavy metal mesh across it.
The green rock on the hillside has repeatedly broken off and periodically sent chunks down onto the roadway. It’s basically sandstone layered with green, volcanic rock called vitric lapilli tuff. It’s not the hardest of rocks, said Douglas County Public Works Director Scott Adams.
“The rock, once it gets weathered on a little bit, it cracks in formations. Water and freezing and different temperatures and stuff then separate it, and it starts deteriorating and falling off,” Adams said.
In 2012, the rock on the hillside started moving.
“This rock cut has been here since the road was established, and it’s had little pop-outs here and there, but it really came down, a large component of it, in 2012 and blocked the road,” Adams said. “We kinda came in and got it to one lane, and we’ve been fighting it ever since.”
The road was completely blocked for a while after the 2012 slide, and again following a subsequent slide November 2017.
The county first applied in 2015 for a federal grant to fix the problem. The grant program is administered by the Federal Highway Administration, and the money is awarded to projects on roads that provide access to federal lands.
The grant was approved in 2016, and from 2017 until this spring, the county has worked with the federal government to finalize the design.
Adams said the county put in a rock catchment system to improve safety while the design for the permanent fix was underway.
“Being able to keep a safe corridor through here, and being able to alleviate our maintenance crews to be able to work on other stuff is just really important. You want motorists to be able to drive through without having to look up,” he said.
Glide-based Triptych Construction, which specializes in rockfall mitigation, is the contractor for the project.
Triptych Site Superintendent Sam Richardson said the project starts with clearing trees and loose brush that’s in the way.
The next step, Richardson said, will be scaling to remove any loose material or rock past the falling edge. This part of the project includes the use of airbags, which he described as “pretty much a giant pillow that deflates and inflates.”
These are inserted into cracks and used to break up unwanted rock.
The pressure forces it to fall off the hill in a controlled manner, rather than in an unexpected and dangerous slide later.
After that, the rock will be bolted to the hillside using pneumatic air drills to create holes into which lengths of steel will be inserted, Richardson said.
The bolting stabilizes the hill by transferring the load from the unstable exterior to the stable and stronger interior of the rock mass, explained Douglas County Public Works Engineering Division Manager Josh Heacock.
Drain holes will also be drilled to help cut back on wintertime erosion. Then a mesh that looks like chain link fencing but is a lot stronger will be stretched out across any section that has loose material, Richardson said.
At the largest chute down which rocks have been sliding, the fence will be angled out from the hill to catch more sliding material.
Adams hopes the project will be completed by the end of the year.
While the work is underway, there will be flaggers during the daytime and traffic lights in the evening. Adams urged drivers to use caution traveling through the area. With a blind corner and no space to pass, ignoring the signal would be very dangerous, Adams said.
Though delays up to 30 minutes are possible, all recreation sites east of the slide area will remain open.