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Environmental Modeling Community of Practice


PEST is a model-independent parameter estimation package which can communicate with any model through the model's own input and output files. PEST can be used for nonlinear parameter estimation and predictive analysis in many different fields of study including ground and surface water hydrology, geophysics, engineering and others.

Current Version: 6.05
Release Date: April 2003
Development Status: General Release
Development Information: Release Notes - changes and known deficiencies
Operating System: DOS
Development Language: FORTRAN
Intended Audience: Hydrologist, Geophysicist, Engineer
Key Words: model, independent, parameter, estimation
Related Web Sites: None Available
Text Files (ASCII Format)
File Name File Description
ABSTRACT.TXT Summary of functions, theory, and applicability.
README.TXT Important installation and usage information.
Download Files
File Type /
File Name /
Format /
File Description
Install /
Self-extracting Zip /
3.0 MB
Setup file for version 6.05 of the PEST system. See README.TXT for important installation information.
Document /
PESTMAN.PDF PEST Model-Independent Parameter Estimation. User's guide for the PEST software.
Install /
Self-extracting Zip /
1.6 MB
The PEST Surface Water Utilities are a suite of programs designed to assist in the use of PEST with surface water models. See README.TXT for important installation information.
Document /
SWUTILS.PDF PEST Surface Water Utilities. User's guide for the optional PEST surface water utilities.
Install /
Self-extracting Zip /
0.9 MB
The modified version of Hydrological Simulation Program - FORTRAN (HSPF) reads numbers contained in input files with greater precision, enhancing its use with PEST. See README.TXT for important installation information.
Document /
HSPF_ALT.PDF Alterations to HSPF Data Input. Describes the changes made to HSPF to enhance its use with PEST.
Install /
Self-extracting Zip /
1.7 MB
The PEST workshop download contains files required to complete the exercises outlined in WORKSHOP.PDF. See README.TXT for important installation information.
Document /
WORKSHOP.PDF Calibrating a HSPF Model Using TSPROC and PEST. Provides lessons which can be applied to the calibration and predictive analysis of environmental models. Files contained in WORKSHOP.EXE are required to complete the exercises.