EPA AGWA
http://www.epa.gov/water-research/automated-geospatial-watershed-assessment-tool
EPA, Registry of EPA Applications, Models, and Databases (READ)
http://ofmpub.epa.gov/sor_internet/registry/systmreg/resourcedetail/general/description/description.do?infoResourcePkId=11982
EPA EnviroAtlas
http://enviroatlas.epa.gov/enviroatlas/tools/agwa.html
EPA Council for Regulatory Environmental Modeling
http://cfpub.epa.gov/crem/knowledge_base/crem_report.cfm?deid=75821
Texas A&M University and the Bureau of Reclamation Hydrologic Modeling Inventory
http://hydrologicmodels.tamu.edu
Ecosystem-Based Management Tools Network
http://ebmtoolsdatabase.org/tool/agwa-automated-geospatial-watershed-assessment-tool
The Landscape Toolbox
http://wiki.landscapetoolbox.org/doku.php/tools:agwa-test
The Nexus Tools Platform
https://data.flores.unu.edu/projects/ntp