Exposure Assessment Models


BASINS (Better Assessment Science Integrating point & Non-point Sources)

photo of water fall

Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) is a multipurpose environmental analysis system designed to help regional, state, and local agencies perform watershed- and water quality-based studies.

It was developed by the U.S. Environmental Protection Agency to assist in watershed management and TMDL development by integrating environmental data, analysis tools, and watershed and water quality models.

Screen shot of analysis dataScreen image of analysis in BASINS

A geographic information system (GIS) provides the integrating framework for BASINS. GIS organizes spatial information so it can be displayed as maps, tables, or graphics. GIS allows the user to analyze landscape information and display relationships among data. Through the use of GIS, BASINS has the flexibility to display and integrate a wide range of information (e.g., land use, point source discharges, and water supply withdrawals) at a scale chosen by the user.

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BASINS makes watershed and water quality studies easier by bringing together key data and analytical components in one tool. BASINS allows users to efficiently access national environmental information, incorporate local site-specific data, apply assessment and planning tools, and run a variety of proven, robust nonpoint loading and water quality models. BASINS is a useful tool for those interested in watershed management, development of total maximum daily loads (TMDLs), coastal zone management, nonpoint source programs, water quality modeling, and National Pollutant Discharge Elimination System (NDPES) permitting.

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Contact Information

BASINS Listserv: Join this online community of BASINS users to exchange questions and answers regarding the use of BASINS.

Join the BASINS listserv by sending an email to lyris@lists.epa.gov, leaving the "Subject:" field blank and putting "subscribe basinsinfo firstname lastname" in the body of the text. Once you have subscribed, you will receive a welcome message confirming your membership.

Search the BASINS listserv archives (as well as other EPA forums to which you are subscribed) by going to https://lists.epa.gov/read/all_forums/.  Login, then go to “My Forums”.  Select the forum you want  (e.g., basinsinfo). Then click on “Search”.  There is also a link for Advanced Search.

You can also contact EPA's BASINS Support Team to find additional information on BASINS not answered through the BASINS Listserv.

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The preferred citation for BASINS is:

US EPA (2015). BASINS 4.1 (Better Assessment Science Integrating point & Non-point Sources) Modeling Framework. National Exposure Research Laboratory, RTP, North Carolina. http://www.epa.gov/exposure-assessment-models/basins. Accessed day month year.

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