USGS Groundwater Information
New & Noteworthy
USGS Groundwater Watch
USGS maintains a network of active wells to provide basic statistics about groundwater levels.
USGS in Your State
USGS Water Science Centers are located in each state.
Other USGS Water Science Areas
FLASH: A Computer Program for Flow-Log Analysis of Single Holes
FLASH (Flow-Log Analysis of Single Holes) is a computer program for the analysis of borehole vertical flow logs. The code is based on an analytical solution for steady-state multi-layer radial flow to a borehole. The code includes options for (1) discrete fractures and (2) multi-layer aquifers. Given vertical flow profiles collected under both ambient and stressed (pumping or injection) conditions, the user can estimate fracture (or layer) transmissivities and far-field hydraulic heads. FLASH is coded in Microsoft Excel with Visual Basic for Applications routines. The code supports manual and automated model calibration.
First official release is version 1.0, released March 7, 2011. FLASH v1.0 has been tested for use with Microsoft Excel 2007 with Visual Basic for Applications routines
Source Code and Documentation
Point of Contact
Support is provided for correcting bugs and clarification of how FLASH is intended to work. Only limited assistance can be provided for applying FLASH to specific problems by contacting the point of contact listed below:
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.
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