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Charles F. Avery

Publications and source records attributed to Charles F. Avery.

4 recordsLinked to original sources
USGS2004

Estimating flood-peak discharge magnitudes and frequencies for rural streams in Illinois

Flood-peak discharge magnitudes and frequencies at streamflow-gaging sites were developed with the annual maximum series (AMS) and the partial duration series (PDS) in this study. Regional equations for both flood series were developed for estimating flood-peak discharge magnitudes at specified recurrence intervals of rural Illinois streams. The regional equations are techniques for estimating flood quantiles at ungaged sites or for improving estimated flood quantiles at gaged sites with short records or unrepresentative data. Besides updating at-site floodfrequency estimates using flood data up to water year 1999, this study updated the generalized skew coefficients for Illinois to be used with the Log-Pearson III probability distribution for analyzing the AMS, developed a program for analyzing the partial duration series with the Generalized Pareto probability distribution, and applied the BASINSOFT program with digital datasets in soil, topography, land cover, and precipitation to develop a set of basin characteristics. The multiple regression analysis was used to develop the regional equations with subsets of the basin characteristics and the updated at-site flood frequencies. Seven hydrologic regions were delineated using physiographic and hydrologic characteristics of drainage basins of Illinois. The seven hydrologic regions were used for both the AMS and PDS analyses. Examples are presented to illustrate the use of the AMS regional equations to estimate flood quantiles at an ungaged site and to improve flood-quantile estimates at and near a gaged site. Flood-quantile estimates in four regulated channel reaches of Illinois also are approximated by linear interpolation. Documentation of the flood data preparation and evaluation, procedures for determining the flood quantiles, basin characteristics, generalized skew coefficients, hydrologic region delineations, and the multiple regression analyses used to determine the regional equations are presented in the main text and appendixes.

Illinois↗
USGS1998

Flood tracking chart for the Illinois River basin

This Flood Tracking Chart for the Illinois River Basin in Illinois can be used to record and compare the predicted or current flood-crest stage to past flood-crest information. This information can then be used by residents and emergency-response personnel to make informed decisions concerning the threat of flooding to life and property. The chart shows a map of the Illinois River Basin (see below), the location of real-time streamflow-gaging stations in the basin, graphs of selected historical recorded flood-crest stages at each of the stations, and sea-level conversion (SLC) factors that allow conversion of the current or predicted flood-crest stage to elevation above sea level. Each graph represents a streamflow-gaging station and has a space to record the most current river stage reported for that station by the U.S. Geological Survey (USGS). The National Weather Service (NWS) predicts flood crests for many of the stations shown on this chart.

Illinois↗
USGS1994

U.S. Geological Survey ground-water studies in Illinois

Ground water is an important source of water supply in Illinois. The largest amount of ground*water withdrawal is in the northern one-third of the State where aquifers to a depth of about 1,500 feet below land surface contain large quantities of potable water. Approximately 74 percent of the public water-supply systems in Illinois use ground water to supply potable water to more than 5.5 million people. Ground-water withdrawals account for almost 25 percent of the total water withdrawn for public water supplies in Illinois. Many public water-supply systems in the Chicago area have recently changed from using ground water pumped from wells to using water delivered from Lake Michigan. The major issues related to ground water in Illinois are: Water- quality degradation or contamination from point and nonpoint sources, and Water availability, because of the lowering of ground-water levels in the bedrock aquifers in northeastern Illinois and elsewhere in the State where pumpage has exceeded aquifer recharge and the susceptibility of the limited surface-water supplies in central and southern Illinois to drought.

Open-File Report↗