Matanuska River erosion near Sutton prompts emergency repairs along Glenn Highway

Lina Portman6 days ago

0 2 minutes read

The Matanuska River erodes the riverbank next to the Glenn Highway Friday at Mile 76 in Chickaloon. Emergency repairs are planned to shore up the river banks and protect the highway. (Loren Holmes/ADN)

PALMER — State transportation officials say they plan emergency repairs next week on an erosion-threatened section of the Glenn Highway near Sutton and are closely monitoring two other sites.

Local residents say the river, swollen by summer snowmelt, has consumed about 40 feet in a month, and has lost more in recent days.

The Matanuska River erodes the bank next to the Glenn Highway Friday at mile marker 63 in Sutton. (Loren Holmes / DNA)

Homes sit on the eroded bank of the Matanuska River next to the Glenn Highway Friday at mile marker 63 in Sutton. (Loren Holmes/ADN)

“It's moving very quickly,” said Chris Rose, who lives in the area and described some driveways that once led to abandoned homes and now lead directly to the river.

The Matanuska River is “a stone's throw” from the highway at Mile 76 near King Mountain and is getting special attention at two other locations about 12 miles closer to Sutton, according to Justin Shelby, regional director of administrative operations for the Alaska Department of Transportation and Utilities. Facilities.

The agency is using accelerated funding for emergency repairs to protect the highway at Mile 76 using large rocks known as riprap by the middle of next week, Shelby said. He could not provide details of funding but estimated the cost to be “tens of thousands.”

The Matanuska River erodes the bank next to the Glenn Highway at mile marker 76 in Chickaloon. (Loren Holmes/ADN)

The other sites will likely also be protected by rockfill, but using the Department of Transportation's conventional design and procurement process because erosion is less imminent, he said.

The Matanuska, an unpredictable glacial river that drains a 2,100-square-mile basin in the Chugach and Talkeetna Mountains, has engulfed riverfront properties from Sutton to Butte, sometimes swallowing entire homes or outbuildings. Buyouts and relocations have been happening for decades as government agencies try to move people away from the river.

Caution tape blocks what was once a driveway as the Matanuska River erodes the bank next to the Glenn Highway at mile marker 63 in Sutton. (Loren Holmes / DNA)

A series of sunny, warm days Friday had raised river levels and flows, according to a National Weather Service gauge on Old Glenn Highway near Palmer.

Yellow caution tape warned of rising waters along a section of the highway. But, Shelby said, the Glenn itself is not in imminent danger.

“The highway probably won't be affected anytime soon,” he said Friday afternoon.