This is Roald Tweet on Rock Island.
You'd think even a river could perform a task as simple as finding its way south from central Minnesota to the Gulf of Mexico. It's all downhill. But not our Mighty Mississippi. It took the Father of Waters years of wandering before he settled on the exact route.
A million years ago, the ancient Mississippi wandered clear over into central Iowa before meandering south. Then came the Pleistocene Epoch—the Age of Glaciers. Each of the four great glaciers which covered much of North America sent the Mississippi searching for a different route. The first glacier, the Nebraskan, pushed the river from central Iowa east to Clinton, creating the palisades one can see at Savannah, Illinois. The second glacier, the Kansan, pushed the Mississippi clear over into central Illinois, where it flowed into the Illinois River at present-day LaSalle-Peru. That old channel, the Meredosia Bottoms, is still visible from an airplane coming into the Quad City Airport.
The third great glacier, the Illinoisan, pushed the Mississippi back into central Iowa, where it drained a large lake—Lake Calvin—and emerged at Keokuk.
Not until the last glacier, the Wisconsin, some twenty thousand years ago, did the Mississippi form Rock Island. The Wisconsin glacier forced the river back from Iowa to flow east and west for 14 miles across a hard limestone outcropping. We Rock Islanders and our island are the new kids on the block. Here, unlike the tall palisades at Savannah, the Mississippi has just begun to wear a channel through the rock. That accounts for the treacherous Rock Island Rapids, which gave steamboats such grief before locks and dams submerged them under nine feet of water.
This long attempt to find its way south may also explain why the Mississippi is one of only a few rivers in the world to have masculine gender. Like every male you and I know, the Father of Waters simply refused to ask directions.
Rock Island Lines with Roald Tweet is underwritten by Augustana College, Rock Island, Illinois.
