The Big Drift is in Glacier National Park, in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

and is an area along the

Going-to-the-Sun Road Going-to-the-Sun Road is a scenic mountain road in the Rocky Mountains of the western United States, in Glacier National Park in Montana. The Sun Road, as it is sometimes abbreviated in National Park Service documents, is the only road that trav ...

where a large amount of winter snow can accumulate to depths of . Located immediately east of

Logan Pass Logan Pass (elevation ) is located along the Continental Divide in Glacier National Park, in the U.S. state of Montana. It is the highest point on the Going-to-the-Sun Road. The pass is named after Major William R. Logan, the first superintenden ...

, the westerly winds push snow over the crest of the

Continental Divide A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not ...

onto the eastern flank of a long

arête An arête ( ; ) is a narrow ridge of rock that separates two valleys. It is typically formed when two glaciers erode parallel U-shaped valleys. Arêtes can also form when two glacial cirques erode headwards towards one another, although frequ ...

which extends south from

Pollock Mountain Pollock Mountain () is located in the Lewis Range, Glacier National Park (US), Glacier National Park in the U.S. state of Montana. Pollock Mountain is situated along the Continental Divide of the Americas, Continental Divide and is one of the pe ...

. West of the divide, this arête is known as the

Garden Wall The Garden Wall is a steep alpine area within Glacier National Park well known during the summer months to be heavily covered in dozens of species of flowering plants and shrubs. Located along the west side of the Continental divide and extendin ...

. As spring approaches, the region is surveyed by helicopter in preparation for

snow removal Snow removal or snow clearing is the job of removing snow after a snowfall to make travel easier and safer. This is done both by individual households and by governments institutions, and commercial businesses. De-icing and anti-icing De-icin ...

that will be needed in order to reopen the Going-to-the-Sun Road for the summer season. By early April, snow removal crews working from either end of the roadway have begun to ascend the steeper east and west slopes of the

Lewis Range The Lewis Range is a mountain range located in the Rocky Mountains of northern Montana, United States and extreme southern Alberta, Canada. It was formed as a result of the Lewis Overthrust, a geologic thrust fault involving the overlying of ...

. The area of the Big Drift is usually reached by late May, and it often can take a month to clear this one stretch of road that is slightly more than in length. Survey crews identify

avalanche An avalanche is a rapid flow of snow down a Grade (slope), slope, such as a hill or mountain. Avalanches can be triggered spontaneously, by factors such as increased precipitation or snowpack weakening, or by external means such as humans, othe ...

hazards and help to locate the road using global positioning equipment. Large

cornices In architecture, a cornice (from the Italian ''cornice'' meaning "ledge") is generally any horizontal decorative moulding that crowns a building or furniture element—for example, the cornice over a door or window, around the top edge of a ...

are usually removed using explosives, then

excavators Excavators are heavy equipment (construction), heavy construction equipment primarily consisting of a backhoe, boom, dipper (or stick), Bucket (machine part), bucket, and cab on a rotating platform known as the "house". The modern excavator's ...

and

front-end loader A loader is a heavy equipment machine used in construction to move or load materials such as soil, rock, sand, demolition debris, etc. into or onto another type of machinery (such as a dump truck, conveyor belt, feed-hopper, or railroad car). ...

s move the snow over the cliffsides or into

dump truck A dump truck, known also as a dumping truck, dump lorry or dumper lorry or a dumper for short, is used for transporting materials (such as dirt, gravel, or demolition waste) for construction as well as coal. A typical dump truck is equipped ...

s. The entire Going-to-the-Sun Road takes about ten weeks to plow, even with equipment that can move 4,000 short tons of snow an hour. By the first of June of each year, the Logan Pass visitor center can usually be reached by vehicle from at least one side of the Continental Divide. In 2011, due to abnormally heavy late winter and early spring snowfall, the Going-to-the-Sun Road did not open until July 13, which, at that time, was the latest opening since the road was built. That record was passed in 2022, when Going-to-the-Sun Road opened July 15, exactly 89 years since the road was dedicated.

References

{{Glacier National Park Going-to-the-Sun Road Glacier National Park (U.S.) Lewis Range