Complex sentence: The South Fork Sauk River headwaters flow from a glacier on the northwest side of Columbia Peak and flows generally northwest through Seventysix Gulch to Monte Cristo, where it is joined by Glacier Creek.
Split into simpler sentences: The South Fork Sauk River's headwaters flow from a glacier on the northwest side of Columbia Peak. The river flows generally northwest through Seventysix Gulch to Monte Cristo, where it is joined by Glacier Creek.