Geomorphic, basin-characteristic, and peak-streamflow data for 50 streams in Ohio

In cooperation with the Ohio Department of Transportation and the U.S. Department 
of Transportation, Federal Highway Administration, the USGS developed a database 
of geomorphic data for a sampling of unregulated natural alluvial streams in Ohio.  
The vector point shapefile that these metadata describe is based on this geomorphic 
database and consists of 50 points and associated attributes.  The database was 
developed as part of a study to develop methods to estimate bankfull characteristics 
of Ohio streams and to relate geomorphic characteristics of Ohio streams to peak 
streamflows of selected recurrence intervals.   The results of the study are presented 
in a report by Sherwood and Huitger (2005).
The database developed for this study consists of geomorphic, basin, and flood-frequency 
characteristics for 50 study sites in Ohio, of which 40 sites are near streamflow-gaging 
stations.  Field surveys were done at each site to collect the geomorphic data.  Bankfull 
indicators were identified and evaluated, cross-section and longitudinal profiles were 
surveyed, and bed- and bank-material were sampled.  Field data were analyzed to 
determine various geomorphic characteristics such as bankfull width, bankfull mean 
depth, bankfull cross-sectional area, bankfull discharge, streambed slope, and bed- 
and bank-material particle-size distribution.  
The various geomorphic characteristics were analyzed by means of a combination of 
graphical and statistical techniques. These techniques resulted in a set of regional curves, 
simple-regression (drainage-area only) equations, and multiple-regression equations to 
estimate bankfull width, bankfull mean depth, bankfull cross-sectional area, and bankfull 
discharge.  Explanatory variables included drainage area, main-channel slope, main-
channel elevation index, median bed-material particle size, bankfull cross-sectional area, 
and local-channel slope.  Average standard errors of prediction for bankfull width equations 
ranged from 20.6 to 24.8 percent; for bankfull mean depth, 18.8 to 20.6 percent; for bankfull 
cross-sectional area, 25.4 to 30.6 percent; and for bankfull discharge, 27.0 to 78.7 percent.  
The simple-regression (drainage-area only) equations have the highest average standard 
errors of prediction.  The multiple-regression equations-in which the explanatory variables 
included drainage area, main-channel slope, main-channel elevation index, median bed-material 
particle size, bankfull cross-sectional area, and local-channel slope-have the lowest average 
standard errors of prediction.
Statistical and graphical analyses were done to investigate development of methods to estimate 
flood-peak discharges from geomorphic characteristics based on the 40 study sites at 
streamflow-gaging stations.   The logarithms of the annual peak discharges for each site 
were fit by a Pearson Type III frequency distribution to develop a flood-peak-frequency relation 
for each site.  The peak-frequency data were related to geomorphic, basin, and climatic 
variables of the 40 study sites by multiple-regression analysis.  The analyses resulted in a set 
of multiple-regression equations to estimate flood-peak 
discharge having recurrence intervals of 2, 5, 10, 25, 50, and 100 years from bankfull cross-sectional 
area, in which the average standard errors of prediction are 31.6, 32.6, 35.9, 41.5, 46.2, and 
51.2 percent, respectively. 
Sherwood, J.M. and Huitger, C.A., 2005, 
Bankfull Characteristics of Ohio Streams and Their Relation to Peak Streamflows: 
U.S. Geological Survey Scientific Investigations Report 2005-5153

Tags: bankfull-bankfull-characteristics-stream-channel-geometry-regional-curves-flood-frequency-flood, usgs-4962f1f2-98df-403a-aa6d-058fb9b4ab1d
Organization: Department of the Interior