Water Pollution Search Results Help - TRI

The TRI Water Pollution Search Results page presents results that meet the search criteria specified on the Search page. Note that the search criteria you entered on the search page appears at the top of the page.

Note the following definitions anywhere they appear on the TRI Search Results page:

  • Direct Discharges: Wastewater released directly into U.S. surface waters
  • Indirect Discharges: Wastewater transferred to publicly owned water treatment works (POTWs) for further treatment prior to release into the environment. The reported TRI chemical release amount is adjusted to account for removals at the POTW.

Click on the links below to quickly find the table of interest.


 Search Statistics - Facility Counts

This table provides information about the number and scope of the facilities included in your search results. Statistics include the total number of TRI facilities, the number of direct and indirect dischargers, and those facilities that link to NPDES permits. The logic and descriptions of each number can be found in TRI Search Statistics Help.

Note that the facility counts and summary tables below do not include pollutants for which annual loadings cannot be calculated, such as temperature and pathogen indicators. Run a separate search for these pollutant categories.

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 Top Chemicals by Toxic-Weighted Pounds (TWPE) (Year)

For a given year, this chart lists the top ten chemicals by name and their total pounds (lb/year) or toxic-weighted pound equivalents (TWPE) (lb-eq/year) reported to TRI as released directly and indirectly. The chemicals are listed in order of decreasing mass and TWPE.

EPA calculates TWPE  using pollutant loadings and chemical-specific toxic weighting factors (TWFs) in order to rank the relative toxicities of different pollutant discharges. TWPE is not a measure of risk or potential for human health impacts. For more information about TWPE, see ECHO Frequently Asked Questions.

For a complete list of chemicals click the "Download All Data" button.

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 Top NAICS Discharges in Pounds/Toxic-Weighted Pounds (TWPE) (Year)

This table lists the ten largest chemical discharges grouped by NAICS code for a given year that meet your search criteria. The NAICS code discharges are ranked in order of decreasing chemical mass. For a complete list of all chemicals grouped by NAICS, select the "Download All Data" button.

NAICS Code/NAICS Description

The facility's 6-digit North American Industry Classification System (NAICS) code and description, which identifies the primary activity of the facility.

Top Chemical

The name of the TRI-listed chemical that identifies the substance discharged.

Direct/Indirect TRI Pounds

For the top chemical for each NAICS code, the annual mass (in units of pound/year) for direct and indirect discharges. This table does not display chemicals that have a total annual load of zero.

Direct/Indirect TRI TWPE

For the top chemical for each NAICS code, the relative toxicities of different pollutant discharges (in units of pounds-equivalent per year) for direct and indirect TRI. This table does not display chemicals that have a total annual load of zero.

Top Pollutant TWPE

For the top chemical for each NAICS code, the relative toxicities of different chemical discharges (in units of pounds-equivalent per year). TWPE is calculated by multiplying the pollutant mass (in pounds) by its toxic weighting factor. This value is not a measure of risk or potential for human health impacts but is a relative measure of the potential toxicity between pollutant discharges. For more information about TWPE, see ECHO Frequently Asked Questions.

Not all chemicals have a toxic weighting factor (for example, Total Suspended Solids), which means that these pollutants do not have a toxicity score (i.e., TWPE = 0).

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 Top Facility Discharges in Pounds/Toxic Weight Pounds (TWPE) (Year)

This table lists the facilities with the ten largest discharges that meet your search criteria. The facility loads are ranked in order of decreasing mass or decreasing toxic-weighted pound equivalents. Click on the facility name to bring up the facility information page. For a complete list of all facility and chemical loads, select the "Download All Data" button to download a CSV file or the "Browse All Facilities" button to view the list on a webpage.

TRI Facility ID

A unique 15-character ID assigned for each facility within the TRI program.

Facility Name

The primary name used to identify a facility in TRI or FRS.

City, State

The city name and two-character state abbreviation for the facility location. City names can be blank in FRS and ICIS-NPDES. The Water Pollution Search will display states for all facilities and the city name, if provided.

NAICS Code

The TRI facility's primary North American Industry Classification System (NAICS) code and description.

HUC-12 Code

Hydrologic Unit Code (HUC) code assigned by the US Geological Survey used to classify watersheds in the United States and the Caribbean.

The Loading Tool obtains this data element using a Watershed Assessment Tracking and Environmental ResultS (WATERS) web service, which obtains the HUC-12 code from the Natural Resources Conservation Service's Watershed Boundary Dataset. The Watershed Boundary Dataset does not include HUC-12's for all NPDES permits in ICIS-NPDES and, by extension, TRI facilities linked to those permits. As a result the HUC-12 can be blank for some facilities in the Loading Tool database.

Top Chemical

Pollutant name(s), which are specifically associated with chemicals that are reported to EPA's TRI Program.

Direct/Indirect TRI Pounds

For the top chemical for each NAICS code, the annual mass (in units of pound/year) for direct and indirect discharges. This table does not display chemicals that have a total annual load of zero.

Direct/Indirect TRI TWPE

For the top chemical for each NAICS code, the relative toxicities of different pollutant discharges (in units of pound-equivalent/year) for direct and indirect TRI releases. This table does not display chemicals that have a total annual load of zero. For more information about TWPE, see ECHO Frequently Asked Questions.

Count of Supplemental Indexes At or Above 80th Percentile (US - Block Group)

Displays a count of supplemental indexes at or above the 80th national percentile for the Census block group that the facility is located in. An "I" indicates the facility is in Indian country, a "T" indicates the facility is in US territories, and the count of indexes is zero. Note that use of this field does not designate an area as an “EJ community” or “EJ facility.” EJScreen provides screening level indicators, not a determination of the existence or absence of EJ concerns. For more information, see the EJScreen home page.

Count of Supplemental Indexes At or Above 80th Percentile (US - 1-Mile Maximum)

Displays a count of supplemental indexes at or above the 80th national percentile for the Census block group within a 1-mile radius of the facility. An "I" indicates the facility is in Indian country, a "T" indicates the facility is in US territories, and the count of indexes is zero. Note that use of this field does not designate an area as an “EJ community” or “EJ facility.” EJScreen provides screening level indicators, not a determination of the existence or absence of EJ concerns. For more information, see the EJScreen home page.

Count of Supplemental Indexes At or Above 80th Percentile (State – Block Group)

Displays a count of supplemental indexes at or above the 80th state percentile for the Census block group that the facility is located in. An "I" indicates the facility is in Indian country, a "T" indicates the facility is in US territories, and the count of indexes is zero. Note that use of this field does not designate an area as an “EJ community” or “EJ facility.”

Count of Supplemental Indexes At or Above 80th Percentile (State – 1-mile maximum)

Displays count of supplemental indexes at or above the 80th state percentile for the Census block group within a 1-mile radius of the facility. An "I" indicates the facility is in Indian country, a "T" indicates the facility is in US territories, and the count of indexes is zero. Note that use of this field does not designate an area as an “EJ community” or “EJ facility.”

Population Density (3 mi)

The number of persons per square mile in the profiled area. The ratio of total persons (displayed in the Total Persons field) to total land area (displayed in the Land Area field).

Percent People of Color (3 mi)

Percent People of Color is the percentage of the population of the given area that consists of people of color. The field is calculated by subtracting the number of persons who are white (and not of Hispanic origin) from the total persons. This number is then divided by the total persons and multiplied by one hundred to determine the percentage.

Percent Low Income (3 mi)

Percent Low Income is the percentage of the population of the given area that has an income less than two times the poverty level, based on the 2015-2019 ACS 5-Year Summary.

Statistics are shown for the area within a 3-mile radius of each facility. The radius is measured from the best available lat/long coordinate. Users should be aware that demographic data are derived based upon the reported latitude and longitude of the facility or permit holder. Surrounding populations and other statistics were estimated by retrieving the data for Census block groups within three miles of each facility.

FRS Tribal Land Code

Displays “Y” if a facility is flagged as being located in Indian Country, based on information from the EPA's Facility Registry Service (FRS). Displays “N” if a facility is not located in Indian Country.

ICIS Tribal Land Flag

Displays “Y” if a facility is flagged as being located in Indian Country, based on information from the EPA's Integrated Compliance Information System (ICIS). Displays “N” if a facility is not located in Indian Country.

Within Spatial Tribal Boundary

Displays “Y” if a facility is located within 25 miles of a tribal spatial boundary as defined by the U.S. Census Bureau tribal boundary layer data for tribes in the lower 48 states and Bureau of Land Management Alaska State Office data for tribes in Alaska. Displays “N” if a facility is not located within or near a tribal spatial boundary. Data Quality Caveat. 

FRS Spatially Derived Tribe

The tribes or tribal territories located within 25 miles of the facility's location. EPA compares the facility location in its Facility Registry Service to the U.S. Census Bureau tribal boundary layer data for tribes in the lower 48 states and Bureau of Land Management Alaska State Office data for tribes in Alaska. The tribal boundary locations identified are suitable only for general spatial reference and do not necessarily reflect EPA's position on any Indian country locations or boundaries, or the land status of any specific location. Data Quality Caveat.