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Wellhead Protection Area (WHPA) Model

WHPA is a semi-analytical groundwater flow simulation program used for delineating capture zones in a wellhead protection area. The program consists of four computational modules: RESSQC, MWCAP, GPTRAC, and MONTEC. WHPA is applicable to homogeneous aquifers exhibiting two-dimensional, steady groundwater flow in an areal plane and appropriate for evaluating multiple aquifer types (i.e., confined, leaky-confined, and unconfined). The model is capable of simulating barrier or stream boundary conditions that exist over the entire depth of the aquifer. WHPA can account for multiple pumping and injection wells and can quantitatively assesses the effects of uncertain input parameters on a delineated capture zone. The program can be used as a postprocessor for two dimensional numerical models of groundwater flow.


Version 2.2
Release Date September 1993
Operating System DOS

Minimum System Requirements

  • IBM PC/AT or compatible
  • DOS version 2.1 (or higher)
  • CGA, EGA, VGA, or Hercules graphics capability
  • 640 KB of RAM


Program and Installation files 1 (ZIP)(416 K)  (416 K)

Program files 2 (ZIP)(364 K)  (364 K)

Addendum to the WHPA Code, Version 2.0, User's Guide: Implementation of Hydraulic Head Computation and Display into the WHPA Code

Installation Instructions

To download and install WHPA, the following procedures must be followed:

  1. Refer to the user's manual for further instructions.
  2. Download program and installation files (1 and 2).
  3. Unzip program and installation files (1) from your hard drive to a blank formatted 3.5-inch high-density diskette labeled "WHPA Disk 1."
  4. Unzip program files (2) to a blank formatted 3.5-inch diskette labeled "WHPA Disk 2."
  5. Insert the disk labeled "WHPA Disk 1" into the 3.5-inch drive.
  6. At the DOS prompt, change drives to the 3.5-inch drive.
  7. Type INSTALL.
  8. Follow the on-screen directions and refer to the user's manual.