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Surface Water Models

The following surface water models were developed by the U.S. Environmental Protection Agency in conjunction with other government, academic, and commercial institutions. To find out more about a particular model, click on a hyper-linked model name in the table below. The models listed are available for download and are subject to the distribution and support policy.

Product Name Operating System Key Words Supported by ORD?
AQUATOX Windows AQUATOX, simulation model, fate prediction, aquatic systems, effect on ecosystem, ecological risk assessments, aquatic ecosystem Yes
BASINS Win XP, Vista, 7, 8, 10 multipurpose environmental analysis system, watershed management, water quality, tmdl, gis framework, analytical components, NPDES Yes
CGEM Linux water quality, nutrients, hypoxia, eutrophication, surface water, sediment, estuary, marine, mechanistic model Yes
DFLOW Win XP, Vista, 7, 8 stream flows, low flow analysis, design flow statistics, daily stream flow records No
EFDC Win 98, NT, 2000, XP surface water, hydrodynamic, sediment-contaminant, eutrophication, rivers, lakes, reservoirs, wetlands, estuaries, coastal ocean regions, assessment, management, regulatory No
EXAMS Win 98, NT, 2000, XP aquatic biology, assessment, biology, chemistry, compliance, environmental effects, metals, NPS related, permits, pesticides, point source(s), rivers, streams, surface water, test/analysis Yes
EXPRESS Win 98, NT, 2000, XP PRZM, EXAMS, exposure, shell No
GCSOLAR Windows 7,8,10 solar, photolysis, half-life, pollutant, aquatic, ozone No
HMS Web Services hydro-informatics, hydrologic micro services, environmental modeling, water quality data provisioning web services, modeling components, precipitation, air temperature, solar radiation, soil moisture, evapotranspiration, surface and subsurface flow, runoff. Yes                                       
HSCTM2D Win 9x, NT hydrology, sediment, contaminant, transport, finite element model, river, estuary No
HSPF Windows XP, Vista, Windows 7, or Windows 8 assessment, biology, compliance, deposition, discharge, environmental effects, estuaries, hydrology, lakes, metals, monitoring, NPS related, NPDES, nutrients, permits, pesticides, point source(s), rivers, sediment, streams, surface water, test/analysis, TMDL related, toxicity No
Low Flow Text only definition and characteristics, low flows, aquatic life criteria, design flows No
PLUMES2.0 Windows surface, water, jet, plume, model, quality, contaminant, TMDL Yes
PRZM3 Win 98, NT, 2000, XP assessment, discharge, environmental effects, hydrology, land use management, metals, pesticides, surface water, test/analysis No
QUAL2K Win ME, 2000, XP aquatic biology, assessment, compliance, discharge, environmental effects, hydrology, NPS related, NPDES, point source(s), surface water, test/analysis, TMDL related No. Please see:
EPA Region 4
RUSLE2 Win 98, NT, 2000, XP rill, interrill, erosion, sediment, overland flow, climate, soil, topography, land use No. Please see:
USDA Agricultural Research Service
SERAFM MS-Excel serafm, exposure, assessment, mercury, hg, surface water, pond, stream, river Yes
SWMM Win 98, NT, ME, 2000, XP aquatic biology, assessment, combined sewer, community, discharge, environmental effects, metals, NPS related, NPDES, point source(s), procedure, rivers, stormwater, streams, surface water, test/analysis, TMDL related No. Please see:
Center for Environmental Solutions and Emergency Response (CESER)
Surface Water Toolbox Win 7, 8 Water Resources, Groundwater and Streamflow Information Program, n-day frequency analysis, compute biologically-based design flows, Flow duration curves No: Please see:
US Geological Service (USGS)
Virtual Beach MS Windows surface water, water bodies, beach, pathogen predictor, multiple linear regression, MLR, best-fit model Yes
Visual Plumes Win 98, NT, 2000, XP surface, water, jet, plume, model, quality, contaminant, TMDL No
WASP Early versions of Windows, 64-bit Windows 7 or higher, Mac OSX, Linux Ubuntu aquatic biology, assessment, compliance, discharge, environmental effects, hydrology, metals, NPS related, NPDES, point source(s), surface water, test/analysis, TMDL related Yes
WHATIF Win XP(SP2) watershed, health, fish, habitat, macro-invertebrate, biodiversity, BASS, biomass, biota, aquatic ecosystem, MAHA, CVI, hydraulic, bankfull, flow, restoration, food web, mercury, PCB, dioxin No
WMOST Windows Excel 2010, 2013, 2016 with Macros Integrated Watershed Management, Optimization, Decision-Support, Green Infrastructure, Tool Yes

Hydrologic Modeling Community of Practice

  • Modeling Products
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Last updated on April 16, 2025
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