The Ausable drains 1,142 square kilometres (441 sq mi) of land, and falls 158 metres (518 ft) in elevation from source to outlet.

In 1875, engineers of the Canada Company engaged in a large scale drainage project, referred to locally as "The Cut", which altered the course of the river dramatically and permitted the draining of several local small lakes and wetlands for agricultural purposes.

The former course of the river, sections of which almost completely dry up during the summer season, can still be seen in Pinery Provincial Park.

The formation of the Ausable Gorge by the river near Arkona has exposed fossils from the Middle Devonian period.

At one time, a hydroelectric plant was located at nearby Rock Glen Falls.