The surest sign of spring in Glacier National Park is not the long sweet note of the varied thrush or the call of swans sweeping over the Continental Divide — it’s the rumble of diesels and the screech of steel digging into a winter’s worth of snow.

Park plow crews hit the pavement April 1, starting with the Camas Road on the west side. After that, they went to work on the Going-to-the-Sun Road, Park spokeswoman Denise Germann said.

Glacier National Park plow crews are now beyond the Avalanche Creek campground, working in the Red Rocks area on the Going-to-the-Sun Road.

Crews had a week of good weather and the road is largely clear of ice and snow up to Avalanche Campground.

The road is gated at Lake McDonald Lodge, but hikers and bikers can go beyond that. While plow crews are working, there’s a closure about a half-mile before Avalanche, but there  generally are no restrictions when crews aren’t plowing.

On the east side of Glacier, crews are working in the Many Glacier Valley, where they’re experiencing larger than normal drifts. The Many Glacier Road remains closed to motor vehicles.

The Camas Road is completely plowed, but isn’t open to vehicles yet, though hikers and bikers can travel the road.

It usually takes Park crews about two and a half months to clear the Sun Road. This will be the first summer in years without construction taking place on the west side of the Sun Road, so the road will open to Logan Pass for motor vehicles when it’s safe and clear of snow, Germann said.

Plow crews have their work cut out for them. This year’s snowpack is running about 128 percent of average for the Flathead River Basin, with higher amounts locally, according to the Natural Resource Conservation Service.

On the east side, construction on the Sun Road continues from Siyeh Bend to Rising Sun. The earliest the Sun Road will open to motor vehicles on the east side is June 20, Germann said.

(Chris Peterson writes for the Hungry Horse News)