Naturally occurring large wood replacement in Killbuck Creek, Ohio, one year after large wood removal. (Aquatic Biology 09:00 AM, Saturday, April 5, 2003 Brewer/Frost Science 109 Dr. Gwynne Stoner Rife-Presiding).

Morris, Arthur E.L. ; Goebel, P. Charles

9:15

Although large wood in rivers may increase flooding by impeding high water flow, large wood in rivers also moderates the energy of floodwaters and greatly increases animal and plant habitat diversity. In 1999, the Ohio General Assembly made available 5 million dollars for the removal of logjams and debris from Ohio rivers to decrease flood risks. A primary question underlies the advisability of such spending: how long does it take for new logjams to form? If new logjams form quickly, then the economics of removal and the impacts on stream ecology must be evaluated in light of this rapid replacement. To test the hypothesis that fewer and/or smaller logjams occurred after wood removal from a river, we georeferenced all new logjams in approximately 16 km of Killbuck Creek, a channelized river in Holmes County, Ohio, 18 months after logjams were cleared from that section of the creek in 2001. The number of new logjams we found exceeded the number recorded by Holmes County personnel in the spring of 2001. River bends, islands, and inflowing tributaries seemed to focus logjam formation. It appeared that much of the new large wood in the river was recruited from floodplain forests and tributary streams. The rapid, natural replacement of large wood in Killbuck Creek suggests that one-time removal of large wood may not be an effective management option if the objective is long-term absence of logjams in similar channelized streams. Consequently, alternative methods of flood mitigation should be considered.

ARTHUR E. L. MORRIS MORRIS.591@OSU.EDU, P. CHARLES GOEBEL GOEBEL.11@OSU.EDU, OHIO STATE UNIVERSITY, OARDC, SCHOOL OF NATURAL RESOURCES, 1680 MADISON AVE, WOOSTER OH 44691-4114