Grey skies and blustery wind didn’t keep dozens of people from packing into the Kenai Senior Center on Wednesday to celebrate the end of work on one of the communities longest-sought projects. It’s a roughly 5,000-foot rock berm along the north shore of the Kenai River. The berm parallels part of the Kenai bluff, which loses about three feet a year due to erosion.
Newly-elected Kenai Mayor Henry Knackstedt is a lifelong Kenai resident. He describes the bluff as the heart of the city’s historical and cultural significance, home to the city’s Old Town and parks where people watch the river and Cook Inlet. But Knackstedt says the bluff’s also been a source of concern.
“Year after year, steady erosion destroyed and threatened homes, businesses, public facilities and sites of cultural and historical importance, we all knew something had to be done,” he said. “Today, we can finally say it's done. The bluff is stabilized.”
It’s been more than a year since the U.S. Army Corps of Engineers, Sen. Lisa Murkowski, local lawmakers and Kenai officials gathered at the top of the bluff for a ribbon cutting ceremony to celebrate ground breaking. Work began in earnest last spring. Crews placed the first rock May 16 and the final rock Oct. 9.
The Corps awarded a roughly $20 million project contract last year. Previous estimates had put the price tag at double that amount. The project picked up $28 million through the federal bipartisan infrastructure bill and another $6.5 million from the state.
Since then, a circuit of barges loaded down with rocks made the 18-day roundtrip journey between Kenai and Sand Point in the Aleutians. Patrick McHugh is the president of Western Marine Construction. That’s the company that built the berm. He says sourcing volcanic rock from Sand Point is intentional – it’s denser, and therefore hardier.
“Rock can have lots of different properties when it comes to the density of it,” he said. “The freeze/thaw is the biggest thing. If it has water absorption and freezes and then splits in parts and breaks, that's where rock deterioration really happens. … This rock from Sand Point does not saturate with water and then freeze and break in half.”
McHugh says the Corps has strict specifications for the rocks that are used to ensure longevity. He says they put the rocks through 100 freeze/thaw cycles over almost six months to monitor degradation. Only after passing those tests does the rock get used.
Drone footage of waves battering up against the rock berm played on monitors around the senior center dining hall Wednesday. The video, captured by the City of Kenai, shows a high tide pushing waves toward the bluff. The water ripples along the rock berm – but doesn’t touch the bluff.
City officials say the video is proof the berm works. But just in case, the Corps says they’ll keep an eye on the project to make sure it performs as intended.
