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