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Impaired Waters and TMDLs

Resources, Tools and Databases about Impaired Waters and TMDLs

Table 1 lists various tools and information for the layperson. Each site is designed to allow citizens to find out more about a specific waterbody in his/her neighborhood or community in an easily understandable format. For most, all one needs is a location, waterbody name or zip code to begin.

Table 2 provides more advanced tools and databases for water resource managers who may be assessing waters, developing TMDLs or planning restoration actions.

Table 1. Tools and Information Sources for the Public

Tool Description
How’s My Waterway A user-friendly search tool that retrieves state-reported water quality conditions from EPA data systems for a user-defined local search area. It allows you to see if your waterway was checked for pollution, what was found and what is being done.
Surf Your Watershed This tool allows one to find citizen-based groups that are working to your watershed. You may want to contact one of these groups to find out about cleanups, monitoring activities, restoration projects and other activities.
Watershed Central This site has been designed to assist users to develop and put into place effective watershed programs. It includes guidance, tools and case studies to help you share information, analyze data and identify opportunities to begin or increase your efforts.
Water Quality Assessment and TMDL Tracking (ATTAINS) ATTAINS contains information on waters that are not supporting their designated uses. These waters are listed by the state as impaired Under CWA section 303(d). The database also tracks the status of TMDLs and actual TMDL reports.
MyEnvironment For more experienced users, MyEnvironment is a search application that provides a cross-section of all environmental information for a specific location. Under the MyWater section, users can access information on all of EPA’s water programs, such as water quality assessment, drinking water and discharge permits, as well as from other sources, such as streamflow data from USGS.
AskWATERS This tool answers multi-program questions drawing on information from a number of linked databases. The Simple Query Tool allows users to tailor frequently asked questions about waters at the State, Region or National level. The Expert Query Tool is a web-based application that allows users to create their own queries and pull 303(d) listing and TMDL information.
MyWATERS Mapper This webpage displays snapshots of EPA Office of Water program data. It depicts the status of NPDES permits for each state, summary information from the clean Watershed Needs Survey and water quality assessments. MyWATERS Mapper also contains water-related geographic themes such as 12-digit watersheds, the national stream network known as the national Hydrography Dataset and other water-related map layers. MyWATERS Mapper enables the user to create customized maps at national and local scales.

Table 2. Regulatory Tools and Databases

Tool Description
Water Quality Assessment and TMDL Tracking (ATTAINS) ATTAINS contains information on waters that are not supporting their designated uses. These waters are listed by the state as impaired Under CWA section 303(d). The database also tracks the status of TMDLs and actual TMDL reports.
Recovery Potential Screening Tool This site provides technical assistance for restoration programs. It helps states consider where to invest their efforts and resources for greater likelihood of success, based on the traits of their own geographic area's environment and communities.
Compendium of Tools for Watershed Assessment & TMDLs (244 pp, 13.2 MB, About PDF) This report contains useful information for selecting appropriate models and supports the watershed approach by summarizing available techniques that assess and predict physical, chemical and biological conditions in waterbodies.
STORET EPA’s STOrage and RETrival data warehouse allows users to enter and retrieve water quality, biological and physical data.
Nitrogen and Phosphorus Pollution Data Access Tool (NPDAT) NPDAT is a web-based tool intended to help states develop effective strategies for reducing nitrogen and Phosphorus pollution. The site consists of an introductory section, geospatial viewer and download tables.
NHDPlus in WATERS The National Hydrography Database (NHD) provides a national framework for assigning reach addresses to water quality related entries, such as dischargers, drinking water supplies, streams affected by fish consumption advisories, wild and scenic rivers, assessed waters under CWA 305(b) and 303(d), designated uses and more.
Environmental Dataset Gateway (EDG) Clip N Ship Clip N ship is an online tool that presents EPA data in a map viewer and allows one to view the data, select the area of interest and choose an output format to save the content locally.
DMR Pollutant Loading Tool The Discharge Monitoring Report (DMR) Pollutant Loading Tool is designed to help users determine who is discharging, what pollutant they are discharging and how much, and where they are discharging. The tool calculates pollutant loadings from permits, DMR data and NPDES Compliance data.