Ecosystems Research Division

UPDATE to EPD-RIV1 Version 1.1 released 2/23/05

EPD-RIV1 is a system of programs to perform one-dimensional dynamic hydraulic and water quality simulations. The computational model is based upon the CE-QUAL-RIV1 model developed by the U.S. Army Engineers Waterways Experiment Station (WES). This modeling system was developed for the Georgia Environmental Protection Division of the Georgia Department of Natural Resources, Dr. Roy Burke III, Program Manager and the U.S. Environmental Protection Agency, Region IV, Dr. Jim Greenfield.

EPD-RIV1 is a one-dimensional (cross-sectionally averaged) hydrodynamic and water quality model. It consists of two parts, a hydrodynamic code which is typically applied first, and a quality code. The hydraulic information, produced from application of the hydrodynamic model, is saved to a file which is read by, and provides transport information to, the quality code when performing quality simulations.

The quality code can simulate the interactions of 16 state variables, including water temperature, nitrogen species (or nitrogenous biochemical oxygen demand), phosphorus species, dissolved oxygen, carbonaceous oxygen demand (two types), algae, iron, manganese, coliform bacteria and two arbitrary constituents. In addition, the model can simulate the impacts of macrophytes on dissolved oxygen and nutrient cycling.

The model was designed for the simulation of dynamic conditions in rivers and streams for the purpose of analyzing existing conditions and performing waste load allocations, including allocations of Total Maximum Daily Loads (TMDLs).

EPD-RIV1 is the result of a series of modifications to the original WES code to improve its performance and add to its capabilities, particularly for performing wasteload allocations. Considerable effort has also been made to make the model easier to use. Several additional programs were developed to aid the user in the development of input datasets for the EPD-RIV1 models and interpret the results. A pre- and post-processors are integrated with the Water Resources Database (WRDB) also developed for Georgia EPD and Region IV EPA. This system provides the user a unique set of tools to aid in the analysis of environmental data, preparation of data for a model application, simulating the impact of time-varying point and non-point sources on the hydrodynamics and water quality of a stream or river, and analyzing model results.

The PreRiv1 preprocessor is organized about the project concept, in which all the files associated with a hydrodynamic and water quality simulation are identified and stored. Input data files are saved in the standard model input format, but can be edited with user-friendly forms especially designed for inputting modeling data; on-line help explains the required input and offers suggestions for reasonable values for kinetic parameters..

Time series data can be manually input, or imported from WRDB or other data sources, mapping one or more stations to model cross sections. The user can interpolate missing values if appropriate, and apply scale and conversion factors during the "build"operation.

PreRiv1 also acts as the control center for viewing data files, running the hydrodynamic and water quality simulation models, examining modeling results using the postprocessor, and running WRDB. When the simulation models are running, intermediate results are displayed in an "interactor"screen; the user can cancel lengthy computations if it apparent that computed results are inappropriate.

The postprocessor is capable of graphically displaying huge (100s of Mb) modeling output files and comparing simulation results with observed data stored in a variety of data sources (usually WRDB). Several graphic formats are available including: time series; longitudinal, depth, and width profiles; frequency histograms and probability plots, and scatter plots. Statistics can be instantly displayed to help the modeler compare various modeling runs or observed data.

PreRiv1 uses spreadsheet-style inpu forms especially designed for inputting modeling data; on-line help explains the required input and offers suggestions for reasonable values for kinetic parameters..

Time series data can be manually input, or imported from WRDB or other data sources, mapping one or more stations to model cross sections. The user can interpolate missing values if appropriate, and apply scale and conversion factors during the "build"operation.

PreRiv1 also acts as the control center for viewing data files, running the hydrodynamic and water quality simulation models, examining modeling results using the postprocessor, and running WRDB. When the simulation models are running, intermediate results are displayed in an "interactor"screen; the user can cancel lengthy computations if it apparent that computed results are inappropriate.

The postprocessor is capable of graphically displaying huge (100s of Mb) modeling output files and comparing simulation results with observed data stored in a variety of data sources (usually WRDB). Several graphic formats are available including: time series; longitudinal, depth, and width profiles; frequency histograms and probability plots, and scatter plots. Statistics can be instantly displayed to help the modeler compare various modeling runs or observed data.

Download EPD-RIV1 (MSI)

EPD-RIV1 Fact Sheet (PDF) (2 pp., 595KB, about PDF)

 Technical Support Center fact sheet (PDF, 2 pp., 733 KB, about PDF)

TMDL fact sheet (PDF, 2 pp., 697 KB, about PDF)