The Pembina Escarpment came up in a conversation recently. Most people have heard of the Pembina River, Pembina Gorge, and Pembina Hills, but I doubt many among us have heard much about the Pembina Escarpment.
The Pembina Escarpment is the boundary between Glacial Lake Agassiz or the Red River Valley and the Glaciated Plains to the west. The term is perhaps more frequently used in association with the area in northeast North Dakota where it is quite prominent, although it has been used to mark the boundary southward to northeast South Dakota as well as in Manitoba. In Manitoba, however, the escarpment is generally known as the Manitoba Escarpment.
The Pembina Escarpment in North Dakota (and again, think the western boundary of glacial Lake Agassiz) runs southward from near Walhalla to western Richland County then into northeastern South Dakota. Northward from the border with Manitoba the escarpment trends northwest where it skirts the east side of Riding Mountain, Duck Mountain, and Porcupine Hills north of Swan River.
The Pembina Escarpment is quite prominent in the area of eastern Cavalier County where the landscape may change from the characteristically flat landscape of the Red River Valley to the east. Westward a rise in elevation of 300-400 feet may occur within a few miles or even less than a mile and change to a hilly landscape with many draws and ravines dominated by oak. For example, when traveling highway 5 between Cavalier and Langdon, the elevation rises considerably to the west of the intersection of highway 32 south of Walhalla. That is the Pembina Escarpment. It is also very noticeable when traveling highway 2 west of Grand Forks. Look for it to the west of the intersection with highway 18.
References to the Pembina Hills or occasionally Pembina Mountain is often rather loosely used to refer to the escarpment as well as the hills associated with the Pembina River from around Walhalla upstream northwestward to the Manitoba boundary.
The Glaciated Plains are very different than the Red River Valley in terms of geology, soils, land use, and more. So, the next time you travel west from the Red River Valley, look for signs of the escarpment. It’s not always obvious, but differences elevation, vegetation, and land use will help you find it.