Seawall planned for Utqiagvik will help protect the Arctic Alaska city from increasingly extreme storms

The ocean near Utqiagvik was bound with ice last week, but strong winds opened the waters back up. Waves running freely can attack the shoreline and damage houses and roads. They can also slowly eat at the land — and with it, cultural sites as well as the sense of safety.

“It’s a losing battle,” said Scott Evans, deputy director of Capital Improvement Program Management at the North Slope Borough. “Every day, we are one step closer to experiencing an event none of us want to. We’re basically rolling the dice.”

A seawall planned for Utqiagvik is aimed at protecting residents from extreme storms while preserving their connection to the ocean.

The North Slope Borough in November approved an additional $300,000 for the U.S. Department of the Army to complete the design of the Barrow Coastal Erosion Mitigation Project. An initial $300,000 in funding came last year.

Since then, engineers have been making plans for a rock wall, taking into account the behavior of the waves, melting ice and the need of whalers, fishermen and other residents to access the ocean.

Potential for severe impacts

Severe coastal storms, such as those in 2015 and 2017, already lead to flooding and erosion around Utqiagvik. Evans said that last year the ocean surface stayed open well into November, and with ice forming later each year, strong winds have a longer window to form large coastal waves.

“Our storm seasons are getting longer, the waters are becoming more ice-free, and our storms are becoming more severe,” Evans said. “We all know it’s a matter of time till we get hit by a big storm.”

The U.S. Army Corps of Engineers evaluated coastal erosion and storms in Utqiagvik and outlined main risks in the 2019 Barrow Alaska Coastal Erosion Feasibility Study.

Strong waves could attack the bluffs on the south end of town, and the homes that sit on top could lose the ground beneath them, engineers concluded in the study. Damage to Stevenson Street, which runs along the beach, could cut off residents close to the Naval Arctic Research Laboratory.

“If it happens to wash out that road, how do we get back and forth to make sure that those folks are provided for?” Evans said.

[From 2015: Barrow’s eroding coastline reveals human bones at Ukkuqsi site]

Residents could lose the only gas station in town and the only tribal college in Alaska, as well as electricity and internet access, according to the study. If the storm waves reach the lagoon area, they could contaminate the only freshwater source in the community, and “it doesn’t take a once-in-a-lifetime storm for saltwater to actually breach the top lagoon,” Evans said.

Sewer infrastructure and an old military landfill are also close to the coast, and if they are damaged, engineers said, contaminants could harm people as well as birds and marine animals.

Every year the borough spends approximately $8.3 million on emergency response and uses most of the local gravel for obstructing and maintaining the temporary berm along the coastline.

“Our public works folks are out actively in the storm repairing the berm while the storm is taking place,” Evans said. “If you don’t do that, (the berm) washes away and you have no protection, so it’s just kind of a big cycle.”

Waiting for a wall

To bring a more permanent solution to the community, engineers recommended raising and revetting Stevenson Street and building a two-layer rock revetment at the bluff area and the lagoon, said Bruce Sexauer, chief of the Civil Works Management Projects Branch with the department. The wall will stretch for about 5 miles along the coast, from the airport past Browerville and to the Naval Arctic Research Facility.

The total cost for the project is estimated at $328.6 million. Federal funding will cover 65%, while 35% — approximately $110.5 million — will come from the North Slope Borough.

The borough is paying for the design phase, but the first part of the construction funding has to come from the federal government. If such funding sources as the Infrastructure Investment and Jobs Act move the project forward, engineers would be able to award a construction contract as soon as fall 2022, Sexauer said.

“We would start construction as soon as we could,” he said. “It’s kind of a limitation of the funding right now.”

Construction should start no later than 2025 to ensure residents’ safety, according to the study by the department. Residents are looking forward to the project’s completion, Evans said.

“If something is not built, people are going to have to look at relocating somewhere,” he said.

Maintaining access

For now, engineers are continuing to design the first segment of the revetment stretching from the airport, planning the height and composition of the wall.

Over the course of the last decade, engineers have done in-depth modeling of the northern Arctic Ocean, looking at the different storm scenarios from different data points — buoys, weather stations and even ships in the ocean, Sexauer explained. Now, they are putting that data into a supercomputer to generate wave conditions and see how the waves would interact with the shoreline and run up on a given structure.

In Utqiagvik, they also need to consider water levels rising and ice forming later and later each year. The wall needs to have several layers of rocks varied in size to protect the shore and the beach against erosion.

The ocean poses a danger for people in Utqiagvik but also stores such resources as whales and fish.

“The sea acts as the store for most of our residents,” Evans said. “All of our North Slope communities rely heavily on subsistence.”

To make sure the wall preserves access to traditional activities, engineers are designing the revetment with access points such as walkways and openings for boat launches.

“We’re working inside a community with a strong cultural history — with the local tribal entities and the whaling captains — to have a good understanding about the cultural significance of the shoreline,” Sexauer said. “One thing that’s particularly important for them is to be able to view the shoreline and access it.”

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