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Watershed Deposition Tool for air quality impacts

What is the Watershed Deposition Tool (WDT)?

The WDT is a software tool for mapping deposition estimates from the Community Multi-scale Air Quality (CMAQ) model to watersheds. It provides users with the linkage of air and water needed for the total maximum daily load (TMDL) and related nonpoint-source watershed analyses. The WDT takes gridded atmospheric deposition estimates from CMAQ and allocates them to user-defined hydrologic cataloging units of rivers and streams (HUCs) within a watershed, state or region and provides output as text or shapefiles.

What are the benefits of using the WDT?

CMAQ model outputs are in the Models-3-Input/Output Applications Programming Interface (I/O API), which is not a commonly used format for watershed analyses. The WDT makes it easy for modelers to make this conversion and perform further analyses.

Who should use the WDT?

The WDT is primarily used by anyone requiring atmospheric deposition estimates as input to watershed analyses. The software only works with specifically post-processed CMAQ output files. Users seeking more flexibility should use the Visual Environment for Rich Data Interpretation (VERDI) program.

How does the WDT work?

The WDT uses the Windows operating system. Users should open the Graphical User Interface (GUI) and utilize CMAQ model output files provided for use with the WDT to create spatial maps of atmospheric deposition. WDT users can use HUC delineations provided with the software or may use their own delineations to utilize deposition to individual or groups of HUCs. Users can then choose to output the results of their analyses as text or shapefiles.

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