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delayed impact calculator

This water resource engineering tool calculates stream-aquifer system attenuation and lag for well-induced surface stream depletion or for stream-incurred return flow from deep percolation to groundwater.  


Update 2024.01.08

Read the manual for detailed description of the finite difference formulation, solution method, and calculation input requirements of the workbook, as well as examples of application to water use scenarios.

No special software is necessary; native Visual Basic for Applications code operates from a tidy Excel spreadsheet interface.  The numerical treatment allows discrete representation of real aquifer configurations, including flexible placement of barriers, meandering streams, and other user-defined features.

Requests for assistance and suggestions for improvement are welcome. 

They may be made with this contact information. 

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