Pleistocene Deposits

At one time the ice front stabilized near Redfield, South Dakota, forming a fairly substantial natural dam that stored meltwater in a temporary lake called Lake Dakota. When the dam was breached, a great flood eroded a large valley that is now known as the James River valley. Once the ice melted completely away, the only water left to feed the river was from rainfall. So today we see a small river lost in the broad floor of the James River valley.