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Environmental Modeling Community of Practice

Total Maximum Daily Load (TMDL) Models and Tools to Assess Exposures

The EPA Center for Exposure Assessment Modeling (CEAM) distributes simulation models and database software designed to quantify movement and concentration of contaminants in lakes, streams, estuaries, and marine environments.

Available Products

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 CEAM distribution and support policy.

Product Name Operating System Key Words Maintained By
Evapotranspiration Calculator Java enabled browser evapotranspiration, et tool, hamon, morton-crae, penman-montieth daily, penman-montieth hourly, priestly taylor, shuttleworth-wallace, class-a pan penpan, open surface penman,  granger-gray, morton-crwe, mcjannett-penman-montieth, time series, TMDL CEAM
Evapotranspiration Desktop Version Windows XP, Vista, Windows 7, or Windows 8 evapotranspiration, et tool, hamon, morton-crae, penman-montieth daily, penman-montieth hourly, priestly taylor, shuttleworth-wallace, class-a pan penpan, open surface penman,  granger-gray, morton-crwe, mcjannett-penman-montieth, time series, TMDL CEAM
GRAY Tool Java enabled browser HSPF, WinHSPF, FTABLE, RCHRES, BMP, assessment, compliance, discharge, environmental effects, hydrology, permits, rivers, sediment, streams, surface water, TMDL related, toxicity CEAM
GREEN Tool Java enabled browser HSPF, WinHSPF, FTABLE, RCHRES, BMP, assessment, compliance, discharge, environmental effects, hydrology, permits, rivers, sediment, streams, surface water, TMDL related, toxicity CEAM
Desktop HDFT Win 9x, NT, XP HSPF, WinHSPF, FTABLE, RCHRES, BMP, assessment, compliance, discharge, environmental effects, hydrology, permits, rivers, sediment, streams, surface water, TMDL related, toxicity CEAM
HDFT Web Version Java enabled browser HSPF, WinHSPF, FTABLE, RCHRES, BMP, assessment, compliance, discharge, environmental effects, hydrology, permits, rivers, sediment, streams, surface water, TMDL related, toxicity CEAM
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 CEAM
Model Performance Tool Java enabled browser Model Performance Evaluation and Scenario Analysis, MPESA, model performance, models predict time series data, streamflow, Hydrological Simulation Program-Fortran, HSPF, Stormwater Management Model, SWMM, evaluation, diagnostics, time series separation and reconstruction, TSSR, descriptive statistics, error analysis, weighted ranks, serial and cross-correlation analysis, Nash-Sutcliffe model efficiency CEAM