We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Exposure Assessment Models

Water Quality Analysis Simulation Program (WASP)

The Water Quality Analysis Simulation Program (WASP7) is an enhancement of the original WASP (Di Toro et al., 1983; Connolly and Winfield, 1984; Ambrose, R.B. et al., 1988). This model helps users interpret and predict water quality responses to natural phenomena and manmade pollution for various pollution management decisions. WASP is a dynamic compartment-modeling program for aquatic systems, including both the water column and the underlying benthos. WASP allows the user to investigate 1, 2, and 3 dimensional systems, and a variety of pollutant types. The state variables for the given modules are given in the table below. The time varying processes of advection, dispersion, point and diffuse mass loading and boundary exchange are represented in the model. WASP also can be linked with hydrodynamic and sediment transport models that can provide flows, depths velocities, temperature, salinity and sediment fluxes. This release of WASP contains the inclusion of the sediment diagenesis model linked to the Advanced Eutrophication sub model, which predicted sediment oxygen demand and nutrient fluxes from the underlying sediments.

WASP is one of the most widely used water quality models in the United States and throughout the world. Because of the models capabilities of handling multiple pollutant types it has been widely applied in the development of Total Maximum Daily Loads (TMDL). WASP has capabilities of linking with hydrodynamic and watershed models which allows for multi-year analysis under varying meteorological and environmental conditions. WASP has been applied to all of the major estuaries in Florida where it was linked with a hydrodynamic and watershed model simulating 12 continuous years to aid US EPA in the development of numeric nutrient criteria. Other examples of its use are: eutrophication of Tampa Bay, FL; phosphorus loading to Lake Okeechobee, FL; eutrophication of the Neuse River Estuary, NC; eutrophication Coosa River and Reservoirs, AL; PCB pollution of the Great Lakes, eutrophication of the Potomac Estuary, kepone pollution of the James River Estuary, volatile organic pollution of the Delaware Estuary, and heavy metal pollution of the Deep River, North Carolina, mercury in the Savannah River, GA.


Top of Page

WASP Preprocessor

The data preprocessor allows for the rapid development of input datasets. The ability to bring data into the model is as simple as cut and paste or queried from a database. The preprocessor provides detailed descriptions of all model parameters and kinetic constants. When linking WASP with hydrodynamic models it is as simple as pointing to the hydrodynamic linkage file.

  • Import time series from WRDB, Spreadsheet, Text Files
  • Automatically import hydrodynamic model interface information
  • Multi-session capable
  • Run time diagnosis

Top of Page

Post Processor

The Post-Processor (MOVEM) provides an efficient method for reviewing model predictions and comparing them with field data for calibration. MOVEM has the ability to display results from all of the WASP models as well as others. MOVEM allows the modeler to displays the results in two graphical formats:

  1. Spatial Grid . a two dimensional rendition of the model network is displayed in a window where the model network is color shaded based upon the predicted concentration.
  2. x/y Plots -- generates an x/y line plot of predicted and/or observed model results in a window.

There is no limit on the number of x/y plots, spatial grids or even model result files the user can utilize in a session. Separate windows are created for each spatial grid or x/y plot created by the user.


Top of Page

WASP Model Information

Current Version 7.52
Release Date November 15, 2013
Operating System Windows 95 / 98 / ME/ 2000 / XP
Intended Audience Environmental Engineers/Scientists, Regulatory Agencies
Key Words aquatic biology, assessment, compliance, discharge, environmental effects, hydrology, metals, NPS related, NPDES, point source(s), surface water, test/analysis, TMDL related
Media Surface Water
Pollutant Types Conventional Pollutants (Nitrogen, Phosphorus, Dissolved Oxygen, BOD, Sediment Oxygen Demand, Algae, Periphyton), Organic Chemicals, Metals, Mercury, Pathogens, Temperature

Top of Page

File Type / Priority Filename / Format / Size File Description
File Download Information
Install / Required Setup WASP 7.52(1 pg, 21 MB)  / Self Extracting Zip File 17.9MB This file contains the WASP Model including the data preprocessor, the kinetic models, graphical post processor, and model documentation. User is encouraged to download the example input files. This file also contains example input files to test model installation. The purpose of these files is for the user to acquaint themselves with the model and test execution. They do not represent a calibrated real world example.
Optional WASP Course This page contains the materials used during EPA Sponsored WASP Workshops. It includes Power Point presentations used for lectures, TMDL example datasets, utility programs and other materials.
Optional WASP Fact Sheet / PDF / 2 pages This file contains a Fact Sheet about the WASP Modeling System in PDF Format.

Top of Page