The Missouri that Lewis and Clark poled up in 1804 was broad, shallow and slow, braided into channels around sandbars and islands, with floodplain forests of giant cottonwoods, marshes and wet prairies along its bottoms. Every flood cut new side channels and oxbow lakes and abandoned old ones. The river's nickname, Big Muddy, came from the sediment it carried.
Straightening the river
Over the century after Lewis and Clark, hundreds of steamboats sank in it, and efforts to control it began. In 1912 Congress authorized the Army Corps of Engineers to keep a six-foot channel from Kansas City to the mouth, 368 miles, with levees and wing dams that pushed the current into one narrow course. In 1945 the Corps began the Missouri River Bank Stabilization and Navigation Project, a channel 300 feet wide and nine feet deep for 735 miles from Sioux City to St. Louis. Rock dikes scoured the bed, meanders and side channels were sealed off, and the river was dredged. The whole Missouri is about two hundred miles shorter than it was in the late nineteenth century.
The work made the bottoms safe to farm. About 300,000 acres of floodplain became farmland, and by the 1980s more than 700 miles of the river had been channelized. The cost fell on what had lived in the shallows. Narrower, deeper and faster water carried less sediment, and the slack water that young fish, amphibians and shorebirds need was mostly gone.
Letting it back in
The Fish and Wildlife Service bought its first parcel for the Big Muddy National Fish and Wildlife Refuge on September 9, 1994, the year after the great flood of 1993. The refuge is a string of separate units on the river's last 367 miles, between Kansas City and St. Louis, almost twenty thousand acres in all. On many of them levees have been cut and the river is allowed onto its floodplain in minor floods. Side channels have been reopened, and willows, cottonwoods, silver maples and box elders have grown into thickets of bottomland forest less than twenty years old.
Three chutes on the refuge formed and work on their own: Cranberry Bend, Boone's Crossing and Lisbon Bottom, on the far bank a few miles from Arrow Rock. Since 2002 the Corps has built three more, at Jameson Island and Overton Bottoms. A chute is a side channel with shallower, slower water than the main river, and the endangered pallid sturgeon, which still swims here, depends on that kind of water for its young. Floods leave another habitat behind. Where water bursts through a levee or road it scours a plunge pool, which locals call a blew hole, and the pond that remains, from one acre to forty, draws fish, turtles, frogs and birds.
On the ground
The refuge aims to keep every unit open to the public for wildlife watching, hunting and fishing. In March 2003 it buried a time capsule in Arrow Rock for the centennial of the national refuge system. Check the river gauge before going out: the refuge asks visitors to stay off the units once the river reaches action flood stage.