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Capture Zone Analytic Element Model (CZAEM)

The Capture Zone Analytic Element Model (CZAEM) is a single-layer model for simulating steady flow in homogeneous aquifers using the Analytic Element Method. It serves as a tool in the wellhead protection decision making process by delineating groundwater capture zones and isochrones of residence times.

CZAEM supports a limited number of analytic elements that can accommodate fairly realistic boundary conditions, such as streams, lakes, and aquifer recharge due to precipitation. CZAEM generates output on groundwater capture zones and residence times, and it accurately defines capture zone boundaries by first determining all stagnation points and dividing streamlines in the flow domain.


  • CZAEM is a public domain model that can be freely copied and distributed.
  • Operating system: Dos
  • Development status: General release

Minimum System Requirements

Hardware Software
  • MS/PC DOS version 5.0 (or higher)
  • DOS extender bound with CZAEM.EXE (provided)
  • ANSI.SYS driver (supplied with DOS)
  • MS/PC DOS version 5.0 (or higher)
  • DOS extender bound with CZAEM.EXE (provided)
  • ANSI.SYS driver (supplied with DOS)

Installation Files

Date Version Download
August 1996 1.1

Program and Installation Files (ZIP)(422 K)  

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

  1. Refer to the user's manual for further instructions.
  2. Download the program and installation files.
  3. After the download is complete, unzip the program and installation files into a new directory called CZAEM on your hard drive.
  4. CZAEM.EXE will start the program in a DOS window.

User's Guide and Related Material