Developed for the Louisiana Department of Environmental Quality by Wiland Consulting, Inc.

View version history (PDF)

To download the most current version that Louisiana DEQ has posted on their website (Version 11.0 as of October 2023), click here and scroll down to the LA-QUAL model link under the heading TMDL Water Quality Modeling. No login is necessary to download this model from the Louisiana DEQ website. An older version of LA-QUAL (Version 9.38) is also available on the Louisiana DEQ website here.

The LA-QUAL model defaults to the Louisiana DEQ defaults. However, for any given version number, the LA-QUAL model will yield identical results to the QUAL-TX model used by the Texas Commision on Environmental Quality (TCEQ) if the the "Model Assumptions" are set to "Texas (TCEQ) defaults" in the menu Preferences/Additional Preferences. LA-QUAL may have newer versions than QUAL-TX with additional enhancements and corrections not available with QUAL-TX. These will be shown in the version history above.

Download zipped file with LA-QUAL executable, User's Manual, and example data set (these downloads require login):

Version 11.02

Version 11.01

Version 11.00

Version 10.03

Version 10.01

Version 9.38

Version 9.37

Version 9.36

Version 9.35

Version 9.34

Version 9.32

Version 9.30