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Kakwa Falls

Kakwa falls is the main attraction of the Kakwa Wildland Provincial Park which is in the Foothills, 150 kilometres southwest of Grande Prairie. Besides being a place of great beauty, it also displays an outcrop of the Cadomin Formation, one of the most prominent ridge and ledge-forming rock deposits in the area. The last portion of the road to the falls is passable only by 4-wheel drive vehicles.

The Kakwa River, fed by Lake Kakwa, is a tributary of the Smoky River. The falls are formed as the river flows over a large anticline, or folded arch of bedrock. Looking downstream from the lookout of the falls, you can see that the prominent Cadomin Formation forming the falls also forms the lip of the canyon. This demonstrates that the falls have moved slowly upstream as the underlying rock was eroded away.

The river plunges a vertical distance of approximately 30 metres. Like most falls, they are the result of a river crossing an outcrop of resistant rock which overlies softer, and more easily eroded rock. Here, the erosion-resistant rock is the Cadomin Formation is a conglomerate, which is often referred to as "nature's concrete," that has thin layers of coal and sandstone. It is made up of rounded pebbles, cobbles, and boulders of multicolored chert and quartzite, with a matrix of well cemented sand. These sediments were deposited as alluvial fans and braided river deposits west of a narrow river channel that once flowed parallel to the then rising Rocky Mountains. As ancient rivers flowed off the steep mountains and into the channel, the break in slope caused the rivers to dump their load of gravel and sand. Around the Kakwa River area, the Cadomin Formation is nearly 26 metres thick, and farther west it reaches thicknesses of 200 metres! This formation is one of the more recognizable rock formations in the Foothills and is an importan important marker for subsurface well logs in oil exploration. During early petroleum exploration, the Cadomin proved to be a major problem for drilling in the Alberta Foothills because its extreme hardness quickly wore out drill bits.

The distinctive feature of these falls is the degree of undercutting that has taken place. There is a large cave behind the falls formed by water splashing and spraying against the back wall of the falls and eroding it. The boundary, or contact, between the upper resistant layer and lower weak layer is what forms the ceiling of the cave.