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About the Online ATTAINS Separate Impaired and Assessed Waters Reports

This guide describes the content (tables, charts, and other features) of the separate Impaired and Assessed Waters Reports format of the ATTAINS web reports. The items are described in the order they appear in the website. For States that submitted an Integrated Report to EPA, a different format is used; see About the Online ATTAINS Integrated Reports. To see if a State provided Integrated or separate reports for recent reporting cycles, see Status of Available ATTAINS Data.

Water Quality Assessment Data for the State: Clickable list of all the tables and charts in the website for the state.

State Websites: Links to each state's water quality assessment report website and its general water quality program. You can visit the state websites for more information on water quality conditions and pollution control programs.

Search for a Waterbody: Enter the name of a specific waterbody in a state (e.g. Black Creek) to retrieve available data for that waterbody (such as location, size, and whether it is impaired).

Total Assessed Waters for the State: The total amount of waters in the state, for each type of water (e.g., river miles, lake acres, bay and estuary square miles), and the amount assessed by the state for the most recent reporting cycle (e.g., 2002, 2004). Assessed waters are those for which monitoring or other types of information have been used by the state to judge whether designated uses are being met.

Assessed Waters by Watershed: The total amount of water assessed, by watershed, where the state provided geographic location data (such the USGS-assigned hydrologic unit code). Within this table, you can click on a watershed name for a list of assessed waterbodies in that watershed and also obtain information such as waterbody size, location, and impairment status. You can also then click on a specific waterbody name for additional detailed information such as causes and sources of impairment. If no watershed names are listed, the state did not provide information for where its assessed waterbodies are located.

Assessed Waters, Individual Use Support for Rivers, Streams, and Creeks: Information on the extent to which the state's assessed river, stream, and creek miles support individual designated uses (such as aquatic life harvesting). The table summarizes the total number of stream miles that were assessed for each use as well as the result of that assessment: "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). States use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Rivers, Streams, and Creeks: The extent to which the state's assessed river, stream, and creek miles support their uses. A stream mile may be assessed for several different uses. In order to be considered "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all assessed uses but if water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Rivers, Streams, and Creeks: The leading pollutants or stressors (such as sediment) that are causing impairment in assessed river, stream, and creek miles in the state. The table also includes the number of stream miles impaired by each cause. While most of the cause names (such as siltation or pH) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Rivers, Streams, and Creeks: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment in assessed river, stream, and creek miles in the state. The table also includes the number of stream miles impaired by each source. While most of the source names (such as agriculture and municipal point source discharges) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Lakes, Ponds, and Reservoirs: Information on the extent to which the state's assessed lake, pond, and reservoir acres support individual designated uses (such as recreation). The table summarizes the total number of lake acres that were assessed for each use as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Lakes, Ponds, and Reservoirs: The extent to which the state's assessed lake, pond and reservoir acres support their uses. A lake acre may be assessed for several different uses. In order to be "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Lakes, Ponds, and Reservoirs: The leading pollutants or stressors (such as non-native aquatic plants) that are causing impairment and the number of lake acres impaired by each cause. While most of the cause names (such as nutrients or metals) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Lakes, Ponds, and Reservoirs: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of lake acres impaired by each source. While most of the source names (such as agriculture and municipal point source discharges) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Bays and Estuaries: Information on the extent to which the state's assessed bay and estuary square miles support individual designated uses (such as recreation). The table summarizes the total number of bay and estuary square miles that were assessed for each use as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Bays and Estuaries: The extent to which the state's assessed bay and estuary square miles support their uses. A bay or estuary square mile may be assessed for several different uses. In order to be rated "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Bays and Estuaries: The leading pollutants or stressors (such as nutrients) that are causing impairment and the number of bay and estuary square miles impaired by each cause. While most of the cause names (such as fecal coliform bacteria) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Bays and Estuaries: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of bay and estuary square miles impaired by each source. While most of the source names (such as agriculture and combined sewer overflows) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Coastal Shorelines: Information on the extent to which the state's assessed coastal shoreline miles support individual designated uses (such as recreation). The table summarizes the total number of coastal shoreline miles that were assessed for each use, as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Coastal Shorelines: The extent to which the state's assessed coastal shoreline miles support their uses. A coastal shoreline mile may be assessed for several different uses. In order to be rated "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Coastal Shorelines: The leading pollutants or stressors (such as fecal coliform bacteria) that are causing impairment and the number of coastal shoreline miles impaired by each cause. While most of the cause names (such as metals or nutrients) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Coastal Shorelines: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of coastal shoreline miles impaired by each source. While most of the source names (such as spills or municipal discharges) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Oceans and Near Coastal Waters: Information on the extent to which the state's assessed square miles of oceans and near coastal waters support individual designated uses (such as recreation). The table summarizes the total number of square miles of oceans and near coastal waters that were assessed for each use, as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Oceans and Near Coastal Waters: The extent to which the state's assessed square miles of oceans support their uses. An ocean and near coastal waters square mile may be assessed for several different uses. In order to be rated "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Oceans and Near Coastal Waters: The leading pollutants or stressors (such as fecal coliform bacteria) that are causing impairment and the number of ocean and near coastal waters square miles impaired by each cause. While most of the cause names (such as metals or nutrients) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Oceans and Near Coastal Waters: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of ocean and near coastal waters square miles impaired by each source. While most of the source names (such as spills or atmospheric deposition) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Wetlands: Information on the extent to which the state's assessed wetland acres support individual designated uses (such as aquatic life uses). The table summarizes the total number of wetland acres that were assessed for each use, as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Wetlands: The extent to which the state's assessed wetland acres support their uses. An acre of wetland may be assessed for several different uses. In order to be rated "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Wetlands: The leading pollutants or stressors (such as siltation) that are causing impairment and the number of wetland acres impaired by each cause. While most of the cause names (such as metals or nutrients) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Wetlands: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of wetland acres impaired by each source. While most of the source names (such as hydrologic modifications) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Great Lakes Shoreline: Information on the extent to which the state's assessed Great Lakes Shoreline miles support individual designated uses (such as aquatic life). The table summarizes the total number of Great Lakes Shoreline miles miles that were assessed for each use as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Great Lakes Shoreline: The extent to which the state's assessed Great Lakes Shoreline miles support their uses. A mile of Great Lake Shoreline waters may be assessed for several different uses. In order to be rated "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Great Lakes Shoreline: The leading pollutants or stressors (such as mercury) that are causing impairment and the number of Great Lakes Shoreline miles impaired by each cause. While most of the cause names (such as pesticides or nutrients) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Great Lakes Shoreline: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of Great Lakes Shoreline miles impaired by each source. While most of the source names (such as atmospheric deposition or contaminated sediments) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Assessed Waters, Individual Use Support for Great Lakes Open Water: Information on the extent to which the state's assessed Great Lakes Open Water square miles support individual designated uses (such as fish consumption). The table summarizes the total number of Great Lakes Open Water square miles that were assessed for each use as well as the result of that assessment -- "good" (the designated use is met), "threatened" (the designated use is currently met but water quality conditions appear to be declining), and "impaired" (the designated use is not met). Note that states use many different designated use definitions. When you are in the national summary page, you can click on the use in the left-hand column to see which state use categories were grouped together for reporting purposes in this national database.

Assessed Waters, Overall Water Quality Attainment for Great Lakes Open Water: The extent to which the state's assessed Great Lakes Open Water square miles support their uses. A square mile of Great Lakes Open Waters may be assessed for several different uses. In order to be rated "good," it must meet all the uses for which it was assessed. It is considered "threatened" if it is meeting all its assessed uses but water quality conditions appear to be declining. It is considered "impaired" if any one of its assessed uses is not met.

Top Ten Causes of Impairments for Great Lakes Open Water: The leading pollutants or stressors (such as mercury) that are causing impairment and the number of Great Lakes Open Water square miles impaired by each cause. While most of the cause names (such as pesticides or nutrients) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Top Ten Probable Sources of Impairments for Great Lakes Open Water: The leading sources (i.e., activities, facilities or conditions) that generate pollution and contribute to impairment. The table also includes the number of Great Lakes Open Water square miles impaired by each source. While most of the source names (such as atmospheric deposition or contaminated sediments) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Causes of Impairment: Lists all pollutants or stressors that are causing impairment in assessed waters of the state and the number of miles, acres, or square miles that are impaired by each cause in each waterbody type. While most of the cause names (such as nutrients or metals) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Probable Sources Contributing to Impairment: Lists all sources that generate pollution and contribute to impairment in all assessed waters of the state and the number of miles, acres, or square miles that are impaired by each source in each waterbody type. While most of the source names (such as agriculture and municipal point source discharges) are standard and widely used by all states, others may be unique to a given state. See the state 305(b) report for more information.

Map of State: Clicking anywhere on this state map will take you to the Enviromapper for Water website, where you can view and map various types of environmental information for the state. This information includes Superfund sites, water discharge permits, toxic releases, and more.

Section 303(d) Fact Sheet for the State: Clickable list of all the tables and charts in the website for the state.

Waters Listed by Waterbody Type: Number of waters on 303(d) list broken down by waterbody type. Select the underlined number to obtain a list of those waters.

Waters Listed by Watershed: Number of waters on 303(d) list broken down by watershed. Select the underlined number to obtain a list of those waters. Select the underlined watershed to obtain a 303(d) fact sheet for the selected watershed.

Map of State: Clicking anywhere on this state map will take you to the Enviromapper for Water website, where you can view and map various types of environmental information for the state. This information includes Superfund sites, water discharge permits, toxic releases, and more.

Causes of Impairment: Clickable list of the causes of impairment for which a water was placed on the 303(d) list. Click on an impairment under the General Impairment Name to obtain a detailed list of causes and numbers of this cause reported. In this table, select a specific cause to obtain a list of the impaired waters. OR Click on the underlined number to obtain a list of impaired waters.

Approved TMDLs by Pollutant: Clickable list of TMDLs developed by pollutant. Click on the pollutant to obtain a list of waters for which a TMDL was or click on the underlined number to obtain a list of TMDLs.

Approved TMDLs by Year: Clickable list of TMDLs approved by fiscal year (October 1 to September 30) since October 1995. Select the underlined number to obtain a list of TMDLs approved for the selected fiscal year.

TMDL Document Search: Search for a TMDL document by entering information specific to the TMDL of interest. Not all TMDL documents are available through this website.