HISTORY OF HUMAN MODIFICATIONS ON BIG BARREN CREEK, SOUTHEAST MISSOURI

This study investigates the history of channelization and its effects on channel conditions in Big Barren Creek. The Big Barren watershed drains 191 km² of the Ozark Highlands in southeast Missouri. Several segments of the creek have been channelized by levee construction and gravel mining. The objectives of this study are to: (1) use historical aerial photography to assess the timing and spatial distribution of channel disturbance and (2) evaluate the influence of both private and public land management practices on geomorphic stability of Big Barren Creek. Approximately 27.2 km of the main stem of Barren Creek were assessed for 11 photo-years ranging from 1930 to 2014. Channel width and bar deposition were used to evaluate channel morphology. In segments where channelization and levee construction was common, channel width has increased by up to four times that of the undisturbed condition. While 43% of the creek is under Forest Service management, 57% is managed for hay pasture/grazing by private landowners. Of the disturbed sections of the channel, 80% is on private lands. Further, of the remaining unstable channels on public land, approximately 14% is related to head-cuts and sediment pulses generated by private activities. Composing about 6% of the disturbed channel length along Big Barren Creek, public land disturbances are generated by road drainage, bridge crossings, and natural bluff obstacles.