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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

• RORA version 2.0 software, documentation, and sample data sets, updated March 2012 (1.6MB EXE)
• README file describing files included in EXE 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.

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