Erosion is an ever-present issue for coastal highways. It’s of particular concern for Kodiak, where a large portion of the major road system sits right alongside the ocean. Starting this spring, the Alaska Department of Transportation & Public Facilities has been working on a months-long construction project to slow the inevitable.
Steve Frey is leaning slightly over the edge of a bluff on the Chiniak Highway overlooking Kalsin Bay.
“I wouldn’t lean against this thing too hard,” he says, pressing lightly on the guardrail, “but you can kind of get an idea here, see how the guardrail is actually exposed.”
We’re at Construction Site 2, 25 miles out from downtown Kodiak. Below him, the thick metal posts holding up the highway guardrails are completely separated from the hillside. The cinderblock anchors that secure the posts are visible too.
Frey, a project engineer consulting for the Department of Transportation and Public Facilities, says that normally this whole support structure should be embedded well underground. But an exposed bluff like this is constantly being battered by ocean swells, winds, and rain, which steadily eat away at the hillside. “It’s gradual,” he says. “It goes pretty quick once it starts going.”
Erosion along the Chiniak Highway is well-documented in borough reports and government surveys. One 1983 study estimated that the bluffs were receding at a rate of five to seven feet per year, on average.
Aurah Landau, DOT Public Information Officer for the Southcoast Region, says there are two main issues endangering the roadway. “There’s erosion occurring along the coastal bluff that has steepened beyond the angle causing sliding and slumping next to the highway,” she says. “And then there’s erosion occurring at bridge and stream culvert crossings from flood events.”
With a roughly $10 million price tag, the Chiniak Highway Erosion Control project spans nine separate sites spread out over more than 20 miles along the highway. It’s a months-long operation that’s been on DOT’s docket for years. Landau says the design process took longer than normal due to the scope of the project.
Among the many complicated considerations that go into a project of this scale are making sure new roads or structures comply with borough code, causing as little impact to the environment as possible, and ensuring that the construction itself doesn’t cause too much of a disturbance to residents or thru-traffic.
Back at Site 2, Jacob Spalinger, a project superintendent for Brechan Construction is standing on a bluff above the eroding highway. “I think to this ditch line is roughly a 28-ft cut,” he says, pointing to a line of of orange explosives markers embedded in the ground. “Where we’re standing, it’s going to be 28 feet lower where we’re standing.”
In order to move the road inland, the crew has to blast part of the hillside away to level it out. It’s a very precise process involving holes drilled deep into the bluff and then filled with specific amounts of explosives. Brechan cuts off road access for about 20 minutes for each blast, but the explosion itself doesn’t take more than a few seconds.
A May 7 blast along the Chiniak Highway. (Video courtesy Louis Rocheleau, Vice President of Brechan Construction)
But even with these careful planning measures, staving off erosion on a coastal highway seems like a losing battle. “These areas are on a steep bluff, and if erosion continues like it is, it could potentially come impact the road again in the future,” says Garrett Paul, construction project manager with DOT.
Does that mean we’ll be back here blasting hillsides again in 30 or 40 years? It’s tough to tell. DOT says designers took measures to “greatly minimize” future erosion using retaining walls and realigning roadways. In site 2, the road is being moved 35 feet inland onto bedrock, which the project officials say will stand up better to the elements than the loose earth where the road is currently situated.
Should erosion continue to be a problem at other places along the 40-mile highway, the state could face a new problem — running out of room to move the road. That’s because the state’s right-of-way corridor only extends 200 ft out from where the road was originally built.
“Yes we would definitely run out of room,” says Paul. “Generally when we do that we purchase properties to move roads, or get easements to construct roads that are outside of our right of way.”
DOT hasn’t had to buy any private property for this project, though they have purchased several easements from property owners along the highway for things like driveway realignments. All negotiations with property owners are confidential, according to DOT Right of Way Chief Greg Weinert.
“I can say that in general, any time you change someone’s property rights, it’s not generally something they want,” Weinert says. “They may understand that it’s for the public good, but it’s still difficult to have things changed. It may have been fair compensation, but that still doesn’t mean there’s not aggravation on the part of the property owner.”
DOT says the project is currently on track to be completed October 31, 2019, with around 10 more blasts scheduled.