HR: 1330h
AN: H43A-04    [Abstracts]
TI: Estimation of Low Streamflow Statistics at Ungauged Sites Using Baseflow Correlation
AU: * Zhang, Z
EM: zzx509@yahoo.com
AF: Environmental Resources Engineering, State University of New York College of Environmental Science and Forestry, 1 Forestry Dr., Syracuse, NY 13210 United States
AU: Kroll, C N
EM: cnkroll@esf.edu
AF: Environmental Resources Engineering, State University of New York College of Environmental Science and Forestry, 1 Forestry Dr., Syracuse, NY 13210 United States
AB: Low streamflow estimates are required for water quality and quantity management purposes. This study focuses on estimation of the 7-day 10-year low flow (Q7,10), an extensively employed low flow statistic in the United States. The baseflow correlation method is an information transfer technique that can be used to estimate low flow statistics at an ungauged site by correlating a nominal number of measured baseflows at the ungauged site with those at nearby gauged sites. A national assessment of baseflow correlation estimators is made via a jackknife simulation with daily streamflow values at more than 1300 USGS HCDN gauged river sites. It is shown that the chosen performance metric is important when evaluating the method across a large range of Q7,10 values. Results confirm that baseflow measurements should be obtained from different baseflow recessions. The method performance is sensitive to the correlation coefficient between baseflows at gauged and ungauged sites when the number of baseflow measurements is 5. When the number of baseflow measurements is 10 or more, the method performs adequately if the correlation coefficient is greater than 0.6. The performance of the baseflow correlation method improves as the number of baseflow measurements increases, but levels off dramatically when one has more than 10 measurements. This research also investigates a number of different baseflow correlation methods that employ information from multiple gauged sites to estimate the Q7,10 at a single ungauged site. Results show that the performance can be improved by using multiple site information, especially when less than 10 baseflow measurements are used.
DE: 1812 Drought
DE: 1854 Precipitation (3354)
DE: 1860 Runoff and streamflow
SC: Hydrology [H]
MN: 2005 Joint Assembly