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Update on the use of the RORA program for recharge estimation.
1U.S. Geological Survey, Reston, VA 20192, USA. rutledgealbert@gmail.com
Ground Water
|May 2, 2007
Summary
This study updates the RORA program for estimating groundwater recharge using streamflow data. It offers guidance to improve recharge estimate reliability by addressing potential errors and comparing methods.
Area of Science:
- Hydrogeology
- Hydrology
- Environmental Science
Background:
- The RORA (Runoff-Recharge) program, initially described in 1994, provides a method for estimating groundwater recharge.
- Accurate groundwater recharge estimation is crucial for sustainable water resource management.
Purpose of the Study:
- To provide an updated guide on the application of the RORA program.
- To enhance the reliability of groundwater recharge estimates derived from streamflow records.
- To address potential sources of error and improve the understanding of the RORA technique.
Main Methods:
- The RORA program utilizes streamflow records to estimate groundwater recharge.
- Key considerations, including the recession index and direct surface runoff, are analyzed.
- Groundwater levels are used for independent assessment of RORA results.
Main Results:
- The updated guidance aims to improve the reliability of automated recharge estimates.
- Potential errors associated with gradual recharge, discharge, and time scale reporting are discussed.
- RORA results are compared and contrasted with manual calculations and other base flow separation techniques.
Conclusions:
- The RORA program offers a valuable tool for estimating groundwater recharge from streamflow data.
- Careful consideration of methodological details and potential errors is essential for accurate application.
- Independent assessment using groundwater levels enhances the validation of RORA-derived recharge estimates.
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