ANCHORAGE -

Warm weather and rapid thawing could soon see weight restrictions imposed on Mat-Su Valley roads.

Borough Director of Public Works Terry Dolan said high temperatures and unusually sunny days over the past few weeks have warmed the subsurface materials beneath valley roads to the point where they are nearly thawed.

That could lead to restrictions as soon as next Wednesday, April 9. Allowing normal traffic as the roads thaw and weaken could result in thousands if not millions of dollars in repairs, Dolan said.

"Some paved roads are already seeping water through cracks indicating the frost under the road is dissipating rapidly,” Dolan said. ”Once thawed, the roadbed will be unable to support heavy traffic for several weeks."

“For normal residents driving normal passenger vehicles, there’s no impact on them,” Dolan said. But for commercial operators and others with heavy vehicles, the restrictions mean loads will be limited to 50 percent of a vehicle’s allowable load limit.

It’s a “normal thing that happens every year” but the unusual winter is leading to an unusual thaw, Dolan said.

“Most of our roads are thawing from the bottom up quicker than they are from the top down,” he said. After January, “winter never really came back” to the Valley and Dolan said intense sunshine has accelerated the process.

Once water in subsurface road materials and soils is absorbed and dried out, the restrictions will be lifted, Dolan said, but that could take weeks, even months.

The southern part of the borough—the “core” area of Palmer and Wasilla extending to the Little Su Bridge on the Parks Highway and to the Granite Creek Bridge on the Glenn Highway—are likely to see restrictions implemented by next week.

Additional restrictions could be added in the north as warm temperatures move there, Dolan added.

City-maintained roads in Houston, Palmer, and Wasilla may also see restrictions.

Restrictions on state roads are listed on the state website.