Could the Mississippi River actually begin in South Dakota? [View all]

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The question by Wendell Duffield, first posed in an essay in 2012, isn’t really new. Other geology texts and scholarly papers have cited similar logic. Nor does Duffield, a geologist who grew up in Browns Valley, Minn., on the South Dakota border north of Big Stone Lake, mean any harm (although he does live a safe distance away in Washington state).

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In other words, while Lake Itasca is the Mississippi’s cultural source, Duffield makes a case that the Minnesota River and the tiny town of Veblen, S.D., is the river’s geologic source.

Here’s why: If you follow the Minnesota River up to Big Stone Lake, that takes you to the Little Minnesota River, which takes you to Veblen.

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We’d be lumbering 11,000 years ago along the River Warren, a huge glacial river that cut a wide valley through what now is central Minnesota, fed by the immense Lake Agassiz, which lay over a continental divide near Browns Valley. In what now is St. Paul, we might have gazed upon River Warren Falls, which dropped 175 feet — taller than Niagara Falls — into a deep gorge.

But over the next 1,000 years, the waterfall eroded the channel back to where Fort Snelling now stands, and where a river from the north (which later became known as the Mississippi) joined the Warren. The waterfall continued its eroding ways up that new channel, eventually forming St. Anthony Falls.

In the meantime, Lake Agassiz finally broke through the ice to the north and began draining toward Hudson Bay. The River Warren, on the south side of the divide, dwindled to a much smaller river.

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http://www.startribune.com/could-the-mississippi-river-actually-begin-in-south-dakota/387864512/