AQUA TERRA Consultants

Downloads & Software

Quick Links to Popular Software Packages

  HSPF   GenScn
  BASINS   (via EPA)   HSPEXP+

EPA manages an active user community that offers support and perspective on BASINS, HSPF, HSPEXP+, and other associated software. To become a member of that community, please subscribe to the listserv following the instructions on EPA BASINS page.

To pursue a more demanding level of support than listserv interactions can provide, please refer to our Premium Support option.

Software Packages Grouped by Client/Agency:

USGS Software available from the Applications page at the Water Resources Division (WRD) of the USGS

  • HSPF User's Manual (in Windows Help format)
  • GenScn (see also our GenScn page)
  • ANNIE A Character-based interactive program designed to help users store, retrieve, list, plot, check, and update spatial, parametric, and time-series data for hydrologic models and analyses. Data are stored in a direct access file called a Watershed Data Management (WDM) file.
  • HSPEXP (HSPEXP is no longer supported by USGS, please refer to HSPEXP+ linked above.)
  • IOWDM A character-based program designed to reformat data to and from a WDM file.
  • SWSTAT Software for statistically analyzing time-series data. The time-series data are read from a Watershed Data Management (WDM) file. The computed statistics and (or) time series can be written back to the WDM file or to a text file.

EPA Software available from the Office of Science and Technology of the Office of Water of the EPA

EPA Software available from the Center for Exposure Assessment Modeling (CEAM) of the EPA

State of Washington Department of Ecology

  • WWHM Western Washington Hydrology Model

San Antonio River Authority

  • SARA Time Series Utility SARA Time Series Utility supports analysis and management of time-varying environmental data including listing, graphing, computing statistics, computing meteorological data and saving in a WDM or text file.
  • SARA Load Reduction Tool The SARA Load Reduction Tool was developed to allow users to determine the constituent load reductions needed to reach water quality standards in model reaches within a watershed through the application of BMPs.

Complementary Professional Services

AQUA TERRA Consultants maintains close professional associations with a number of complementary consulting firms and clients. We encourage you to visit the following sites:

CH2M Hill

CH2M Hill provides expertise in watershed assessments, planning and modeling, public involvement, GIS and database management, bio-assessments, hydrology, hydraulics, hydrogeology, and Best Management Practice (BMP) planning and design.

Computational Hydraulics

Computational Hydraulics, International - specialists in stormwater management activities including developing and supporting software, conducting short courses on stormwater management modeling, and publishing the quarterly newsletter 'SWMM News & Notes'

HydroGeoLogic, Inc.

HydroGeoLogic, Inc. provides advanced technical consulting services for environmental investigation and remediation, water resource assessment, and numerical modeling and computer simulation. Offers strong groundwater and multi-media assessment capabilities.

Dynamic Solutions, LLC a small, woman-owned firm that specializes in water resource engineering including 1,2 or 3-dimensional hydrologic, hydrodynamic, sediment transport and water quality modeling. Expertise in EFDC, CEQUALW2, and WASP for watershed planning, flood studies, thermal and mixing zone studies, and TMDLs.

Clear Creek Solutions specializes in computer modeling of complex hydrologic and hydraulic systems.

Data Sources and Other Useful Links

King County

King County Department of Natural Resources and Parks This web site provides public access to rainfall, streamflow and other hydrologic data collected at King County, Washington, gage sites.


The American Association of State Climatologists in conjuction with NOAA offer maps, weather and climate information, and links to related resources are provided for the entire U.S., presented and organized within six geographic sub-regions. NOAA's National Climatic Data Center offers climate data - surface and upper air observations and products generated from these observations.


PRISM Climate Group offers digital climate maps, including precipitation, temperature, snowfall, degree days, and dew point.


Earthinfo the leading commercial supplier of environmental data on CD-ROMs. Data sources include NCDC, USGS, EPA, Environment Canada, GHCN, and COADS.


USGS water data includes real-time water data, historical records of daily streamflow and peak flows for almost 20,000 stations, a collection of high-quality records from the water quality monitoring network, and a suspended-sediment database.


Watershed and Water Quality Modeling Technical Support Center