[ skip to content ]

The Enhanced Stream Water Quality Model (QUAL2E) is a steady state model for conventional pollutants in branching streams and well mixed lakes.
QUAL2EU can be operated either as a steady-state or dynamic model and is intended for use as a water quality planning and regulartory tool. The model can be used to study impact of waste loads on instream water quality and identify magnitude and quality characteristics of non-point waste loads.
It can simulate up to 15 water quality constituents in any combination desired by the user. The model is applicable to dendritic streams that are well mixed. It uses a finite-difference solution of the advective-dispersive mass transport and reaction equations. The model is intended for use as a water quality planning tool. The Enhanced Stream Water Quality Model with Uncertainty Analysis (QUAL2EU) is an enhancement to the QUAL2E model that allows the user to perform uncertainty analysis. Three uncertainty options are available. Three uncertainty options are employed in QUAL2E-UNCAS: sensitivity analysis, first order error analysis, and Monte Carlo simulation. AQUAL2 is an interactive data preprocessor program for the QUAL2E and QUAL2EU models. AQUAL2 can be used to build input data files for either model. Q2PLOT is an interactive data post processor program for both.
Detailed model description, input requirement and output information, and system requirements are available.
Original EPA's QUAL2E program for MS Windows will not run either from the BASINS interface or as a stand-alone application under Windows 2000 and Windows NT operating systems. If you're using either Windows 2000 or NT, please download QUAL2E program for Windows NT & 2000.
File (for Windows NT & 2000) Size Download
QUAL2EU program for MS Windows NT & 2000 1.1 MB
QUAL2EU user manual for MS Windows (PDF format) 0.35 MB
Installation Guide for QUAL2EU for MS Windows NT & 2000 5 KB
Guide for "How to Run QUAL2EU under Windows NT & 2000"
 5 KB
File (for Windows 9x) Size Download
QUAL2EU program for MS Windows 9X 1.22 MB
QUAL2EU user manual for MS Windows (PDF format) 0.35 MB
QUAL2EU user manual for MS Windows (WP format) 0.45 MB
File (for MS-DOS) Size Download
QUAL2EU model v3.22 (program only) 2.21MB
QUAL2EU model v3.22 installation image and data set, zipped -- Use this if you have a difficulty with EPA's installation program 1.61MB
QUAL2EU FORTRAN source codes 166KB
QUAL2EU v3.22 User Manual in PDF format (Zipped) 7.00MB