Links
- Document: Report (6.3 MB pdf) , HTML , XML
- Table: Tables 1.1 and 1.2 (csv)
- Data Release: USGS data release - Data in support of flow frequency report—Magnitude and frequency of peak and low flows in the Elkhorn River Basin, Nebraska, 1881–2022
- NGMDB Index Page: National Geologic Map Database Index Page (html)
- Download citation as: RIS | Dublin Core
Abstract
Flood-frequency analysis is based on records of annual maximum instantaneous flows observed at long-term streamgages with 10 years or more of operation. Since the last flood-frequency analysis in Nebraska, an additional 30 years of annual peak-flow data have become available, and new flood-frequency analysis techniques have been developed. Moreover, the Elkhorn River Basin in north-central and eastern Nebraska has experienced two of the three highest magnitude floods on record in 2010 and 2019. The U.S. Geological Survey, in cooperation with the Nebraska Department of Transportation, analyzed flow frequency at streamgages in the Elkhorn River Basin in Nebraska.
Flow data from the U.S. Geological Survey and the Nebraska Department of Water, Energy, and Environment annual hydrographic reports were utilized to analyze peak flows. The Peak flow FreQuency (PeakFQ) software was used to perform a flood-frequency and nonstationarity analysis on the selected streamgages in the Elkhorn River Basin in Nebraska. Results of the peak-flow nonstationarity analysis indicate that, of the 23 streamgages analyzed for peak-flow frequency, 4 showed trends that were likely increasing for annual peak flows, whereas 3 indicated trends that were somewhat likely to be increasing. For 11 streamgages, the trend was categorized as about as likely as not, meaning there is less than a 70-percent chance of the trend being either upward or downward. Additionally, 2 streamgages exhibited trends that were somewhat likely to be decreasing, and 3 streamgages showed trends that were likely decreasing.
Low-flow streamflows and nonstationarity in the Elkhorn River Basin were analyzed for low flow periods representing the 1-day, 7-day, and 30-day flows at 21 streamgages using the Hydrologic Toolbox software. Spatially, the nonstationarity analysis results indicated likely increasing or somewhat increasing trend likelihoods for the 1-day, 7-day, and 30-day low flows for many of the Elkhorn streamgages downstream from the Elkhorn River at Ewing, Nebr., streamgage (U.S. Geological Survey station 06797500) and on eastern tributaries during the period of record.
Suggested Citation
Strauch, K.R., and Dietsch, B.J., 2026, Magnitude and frequency of peak and low flows in the Elkhorn River Basin, Nebraska, 1881–2022: U.S. Geological Survey Scientific Investigations Report 2026–5004, 17 p., https://doi.org/10.3133/sir20265004.
ISSN: 2328-0328 (online)
Study Area
Table of Contents
- Abstract
- Introduction
- Purpose and Scope
- Previous Studies
- Site Selection
- Statistical Methods
- At-Station Flow Statistics in the Elkhorn River Basin
- Summary
- References Cited
- Appendix 1. Recurrence Interval and Corresponding Exceedance Floods, and Non-Exceedance Flow for the 1-Day, 7-Day, and 30-Day Low Flows for Streamgages in the Elkhorn River Basin
| Publication type | Report |
|---|---|
| Publication Subtype | USGS Numbered Series |
| Title | Magnitude and frequency of peak and low flows in the Elkhorn River Basin, Nebraska, 1881–2022 |
| Series title | Scientific Investigations Report |
| Series number | 2026-5004 |
| DOI | 10.3133/sir20265004 |
| Publication Date | June 08, 2026 |
| Year Published | 2026 |
| Language | English |
| Publisher | U.S. Geological Survey |
| Publisher location | Reston, VA |
| Contributing office(s) | Central Plains Water Science Center |
| Description | Report: iv, 17 p.; 2 Appendix Tables; Data Release |
| Country | United States |
| State | Nebraska |
| Other Geospatial | Elkhorn River basin |
| Online Only (Y/N) | Y |
| Additional Online Files (Y/N) | Y |