New & Noteworthy

  TWRI-B3 Chapter 2: Introduction to Ground-Water Hydaulics [12MB PDF], now with internal document links added

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  Groundwater Technical Procedures of the USGS

 WTAQ Version 2 — Computer program for calculating drawdowns and estimating hydraulic properties for confined and water-table aquifers

 FLASH: A Computer Program for Flow-Log Analysis of Single Holes

USGS in Your State

USGS Water Science Centers are located in each state.

RORA: The recession-curve-displacement method for estimating recharge

This web site includes information about the use of the RORA computer program for analyzing a streamflow record. The version at this site will read streamflow data in the format that is available from USGS web sites.

The computer program RORA estimates groundwater recharge using the recession-curve-displacement method. The method is based on the change in total potential groundwater discharge that is caused by each recharge event.

RORA Downloads

• Download RORA software executable files and sample data sets (690kb ZIP file, updated January 2007)
• Download README file describing files included in ZIP file
• Download fortran source code (10KB ZIP file)
• Download user's manual (50KB PDF file)

Background Literature

The user's manual does not include complete explanation of the computer program; the program user is referred to the documentation report (first item below). Additional information is provided below.

• Computer programs for describing the recession of ground-water discharge and for estimating mean ground-water recharge and discharge from streamflow records: USGS WRIR 98-4148.
• Considerations for use of the RORA program to estimate ground-water recharge from streamflow records: USGS OFR 00-156.
• Testing an automated method to estimate ground-water recharge from streamflow records: Ground Water, vol. 32, no. 2, pp. 180-189, 1994.
• Use of RORA for complex ground-water flow conditions: USGS WRIR 03-4304
• Obtaining streamflow data from a USGS web site.
• USGS Water Resources Applications Software
• USGS Ground-Water and Surface-Water Interactions web site.

Point of Contact

Comments about this site can be sent to Paul Barlow.

Other USGS Groundwater Software

The USGS develops groundwater, water-quality, surface-water, and other water-resources software for use by the USGS in fulfilling its mission. Most of this software is available online for download at no charge.

Disclaimers and Notices

Please refer to the USGS Software User Rights Notice for complete use, copyright, and distribution information. The USGS provides no warranty, expressed or implied, as to the correctness of the furnished software or the suitability for any purpose. The software has been tested, but as with any complex software, there could be undetected errors. Users who find errors are requested to report them to the USGS.

References to non-USGS products, trade names, and (or) services are provided for information purposes only and do not constitute endorsement or warranty, express or implied, by the USGS, U.S. Department of Interior, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

Note: Some or all of this information is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of the free Adobe Reader from the Adobe web site.  Visit http://www.adobe.com/accessibility/  for free tools that allow visually impaired users to read PDF files.