Impaired Streams, Minnesota, 2018

This page last updated: 02/06/2019
Metadata created using Minnesota Geographic Metadata Guidelines

Go to Section:
1. Overview
2. Data Quality
3. Data Organization
4. Coordinate System
5. Attributes
6. Distribution - Get Data
7. Metadata Reference

Section 1 Overview
Originator Minnesota Pollution Control Agency
Title Impaired Streams, Minnesota, 2018
Abstract This is a set of the impaired streams as determined by MPCA's surface water quality assessment process proposed for the 2018 reporting cycle to US Environmental Protection Agency (EPA). Streams declared impaired prior to 2018 are also included in this dataset unless they have been delisted. EPA approved the data without requesting any changes in January, 2019.

Note that for the purpose of submitting the impaired waters list to EPA, waterbodies partially or wholly within Indian reservation boundaries are published in separate datasets. The MPCA still considers these waters impaired and has an interest in restoring them. The MPCA respectfully requests that the waters partially or wholly within Indian reservations be symbolized differently on map products so that viewers can differentiate them from waters not intersecting Indian reservations.

These streams are a subset and enhancement of the 1:24,000 scale National Hydrography Dataset (NHD). In cases where the NHD does not include a stream reach that MPCA has assessed, a feature is added by MPCA. Since the impaired streams are a small subset of the NHD, only that subset is included in the dataset. This dataset includes impaired streams which have not yet had a TMDL plan approved by the US EPA, those that have a US EPA approved TMDL plan as well as those waters that do not need a TMDL plan.

To be notified of updates to this shapefile, please send an email to
Purpose These data are intended to be used for planning, informational, and cartographic purposes related to surface water quality in Minnesota.
Time Period of Content Date 02/06/2019
Currentness Reference These data reflect the state of the MPCA's surface water assessment database as of the dataset publication date.
Progress Complete
Maintenance and Update Frequency None Planned
Spatial Extent of Data State of Minnesota
Bounding Coordinates

Place Keywords Minnesota
Theme Keywords inlandWaters, surface water, water chemistry, water quality
Theme Keyword Thesaurus ISO 19115
Access Constraints None
Use Constraints
Contact Person Information Kristofor Parson, Data Specialist
Minnesota Pollution Control Agency
525 S. Lake Ave.
Duluth, MN  55802
Phone: 218-302-6622
Browse Graphic None available
Associated Data Sets Detailed information regarding the impaired waterbodies is available in spreadsheet form here:

Section 2 Data Quality
Attribute Accuracy
Logical Consistency These data have been audited to ensure every waterbody included in the proposed 2018 list of impaired waters has a corresponding feature within this spatial dataset. Date of test: 4/3/2018
Completeness These data contain a feature for every waterbody in the draft impaired waters dataset. High-resolution NHD is the primary dataset from which these features are drawn. If no feature exists in the NHD, a custom feature is added.
Horizontal Positional Accuracy Statements of horizontal positional accuracy are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For horizontal accuracy, this standard is met if at least 90 percent of points tested are within 0.02 inch (at map scale) of the true position. Additional offsets to positions may have been introduced where feature density is high to improve the legibility of map symbols. In addition, the digitizing of maps is estimated to contain a horizontal positional error of less than or equal to 0.003 inch standard error (at map scale) in the two component directions relative to the source maps. Visual comparison between the map graphic (including digital scans of the graphic) and plots or digital displays of points, lines, and areas, is used as control to assess the positional accuracy of digital data. Digital map elements along the adjoining edges of data sets are aligned if they are within a 0.02 inch tolerance (at map scale). Features with like dimensionality (for example, features that all are delineated with lines), with or without like characteristics, that are within the tolerance are aligned by moving the features equally to a common point. Features outside the tolerance are not moved; instead, a feature of type connector is added to join the features.
This statement is generally true for the most common sources of NHD data. Other sources and methods may have been used to create or update NHD data. In some cases, additional information may be available from the data provider upon request.
Lineage The processes used to create and maintain high-resolution NHD data can be requested from MPCA. Because NHD data can be downloaded using several user-defined areas, the process descriptions can vary for each download. The NHDMetadata table contains a list of all the process descriptions that apply to a particular download, and those descriptions can be associated with the impaired waters features by MPCA staff upon request. For information on specific waterbodies contact MPCA.

Section 3 Spatial Data Organization (not used in this metadata)

Section 4 Coordinate System
Horizontal Coordinate Scheme Universal Transverse Mercator
UTM Zone Number 15
Horizontal Datum NAD83
Horizontal Units meters

Section 5 Attributes
Overview All streams contained in this shapefile are on the proposed 2018 Impaired Waters list prepared by the Minnesota Pollution Control Agency.

AUID: Assessment Unit ID. This AUID constitutes a unique identifer for each stream reach in the dataset.

CAT: EPA Consolidation Assessment and Listing Methodology [CALM] category, which integrates the 305(b) Report with the 303(d) TMDL List.
The five categories in CALM are as follows:
Category 1: all designated uses are meeting water quality standards
Category 2: some uses are meeting water quality standards and there are insufficient data to assess other uses
Category 3: there are insufficient data to assess any uses
Category 4: at least one use is impaired, but a TMDL is not required
Category 5: at least one use is impaired and a TMDL is required. These become the List of impaired waters.

A reach can only be placed into one Category. For example, if a reach is impaired for one pollutant but the other uses are being met, and a TMDL is required, that reach would be placed into Category 5. Furthermore, if the reach is impaired for more than one pollutant, the reach must stay in Category 5 until ALL pollutants have EPA-approved TMDL plans.

For 'bookkeeping' purposes Category 4 can be sub-divided, and has the following five sub-categories:
4A: Impaired, but a TMDL study has been approved by EPA
4B: Impaired, but a TMDL study is not required because water quality standards are expected to be met in the near future
4C: Impaired, but a TMDL study is not required because the impairment is not caused by a pollutant
4D: An assessment unit is impaired or threatened but doesn't require a TMDL because the impairment is due to natural conditions with only insignificant anthropogenic influence. To be considered 'insignificant', the elimination of the anthropogenic influence would not lead to the attainment of water quality standards and it would not be included in formal pollution reduction goal-setting activities. A reach-specific water quality standard based on local natural conditions has yet to be determined. Upon determination, the assessment unit will be considered non-impaired for the natural conditions and re-categorized to an appropriate category.
4E: Impaired or threatened but existing data indicates a TMDL is not required because impairment is solely a result of natural sources; a final determination of Category 4D will be made in the next assessment cycle pending confirmation from additional information (i.e. water quality or land use).

CAT_DESC: A brief description of the applicable CALM category.

NAME: Name of the lake associated with the AUID.

REACH_DESC: The description of the waterbody location.

USE_CLASS: Use class per MN Statute 7050.0470.

LENGTH_MI: The length, in miles, of the stream reach (assessment unit).

AFFECTED_U(SE): Impaired Use(s)
Possible Values:
AQL: Aquatic Life
AQR: Aquatic Recreation
AQC: Aquatic Consumption
DW: Drinking Water
LRV: Limited Resource Value

Impairment Fields
The following 8 fields contain parameters for which the waterbody is impaired. A complete list of parameter abreviations and their associated pollutants can be found below, in the Year First Listed portion of the metadata document.

LIKE_MEET: Parameter(s) not requiring a TMDL because they meet the requirements for CALM Category 4B, above.

NON_POLL: Parameter(s) not requiring a TMDL because they meet the requirements for CALM Category 4C, above.

NAT_BACK: Parameter(s) not requiring a TMDL because they meet the requirements for CALM Category 4D, above.

ADD_MON: Parameter(s) not requiring a TMDL because they meet the requirements for CALM Category 4E, above.

APPROVED: The parameter(s) for which TMDL plans have been approved (CALM Category 4A) .

NEEDS_PLN: The pollutant(s) for which TMDL plans must be developed and approved.

IMP_PARAM(ETERS): Parameters listed in APPROVED and NEEDS_PLN that cause the stream to be impaired.

NEW_IMPAIR(MENTS): Parameters proposed to be listed for the first time in the reporting cycle of the dataset.

Potential values for impairment parameters in the above fields:
Ace: Acetochlor
Al: Aluminum
Amm-U: Ammonia, unionized
As: Arsenic
Cl-: Chloride
Clpyr: Chlorpyrifos
ColdWater: Lack of cold water assemblage
Cu: Copper
DO: Dissolved oxygen
Dieldrin: Dieldrin
Dioxin: Dioxin (including 2,3,7,8-TCDD)
E.coli: Escherichia coli
FC: Fecal Coliform
FishesBio: Fishes bioassessments
Hg-F: Mercury in fish tissue
Hg-W: Mercury in water column
InvertBio: Aquatic macroinvertebrate bioassessments
Nitrates: Nitrates
Nutrients: Nutrient/eutrophication biological indicators
PCB-F: PCB in fish tissue
PCB-W: PCB in water column
PFOS-F: Perfluorooctane Sulfonate (PFOS) in fish tissue
PFOS-W: Perfluorooctane Sulfonate (PFOS) in water column
T: Turbidity
TSS: Total suspended solids
Temp: Temperature, water
Toxaphene: Toxaphene
pH: pH

HUC_8: The numeric code of the 8 digit Watershed Boundary Dataset (WBD) polygon that this waterbody is primarily associated with.

HUC_8_NAME: The name of the DNR major watershed that this waterbody is primarily associated with.

HUC_4: The numeric code of the 4 digit Watershed Boundary Dataset (WBD) polygon that this waterbody is primarily associated with.

BASIN: The name of the basin (HUC4) in which this waterbody is located.

COUNTY: The name of the county that the majority of this waterbody, or the sampling sites, intersects.

TRIBAL_INT: Values include None, Partially, and Wholly. Depicts the intersection relationship between the waterbody and Indian reservations.

INDIAN_RES: The name of the tribe who's reservation the waterbody intersects.

Year first listed fields:
These fields indicate the first reporting cycle that the impairment was included in the impaired waters list

ACE: Acetochlor
CLPYR: Chlorpyrifos
DO: Dissoved Oxygen
E_COLI: Escherichia coli
FC: Fecal Coliform
FISHESBIO: Fish Index of Biological Integrity
HG_F: Mercury in Fish Tissue
HG_W: Mercury in the Water Column
INVERTBIO: Aquatic macroinvertebrate bioassessments
LCWA: Lack of cold water assemblage
NUTRIENTS: Nutrient/eutrophication biological indicators
PCB_F: PCB in Fish Tissue
PCB_W: PCB in water column
PFOS_F: Perfluorooctane Sulfonate (PFOS) in Fish Tissue
PFOS_W: Perfluorooctane Sulfonate (PFOS) in water column
TSS: Total suspended solids
TEMP: Temperature, water

Shape_Leng(t): The length of the stream reach in meters.
Detailed Citation
Table Detail:

Section 6 Distribution
Publisher Minnesota Pollution Control Agency
Publication Date 02/06/2019
Contact Person Information Kristofor Parson, Data Specialist
Minnesota Pollution Control Agency
525 S. Lake Ave.
Duluth, MN  55802
Phone: 218-302-6622
Distributor's Data Set Identifier Impaired Streams, Minnesota, 2018
Distribution Liability NOTICE: The Geographic Information System (GIS) Data to which this notice is attached are made available pursuant to the Minnesota Government Data Practices Act (Minnesota Statutes Chapter 13). THE GIS DATA ARE PROVIDED TO YOU AS IS AND WITHOUT ANY WARRANTY AS TO THEIR PERFORMANCE, MERCHANTABILITY, OR FITNESS FOR ANY PARTICULAR PURPOSE. The GIS Data were developed by the Minnesota Pollution Control Agnecy for its own internal business purposes. The Minnesota Pollution Control Agency does not represent or warrant that the GIS Data or the data documentation are error-free, complete, current, or accurate. You are responsible for any consequences resulting from your use of the GIS Data or your reliance on the GIS Data. You should consult the data documentation for this particular GIS Data to determine the limitations of the GIS Data and the precision with which the GIS Data may depict distance, direction, location, or other geographic features. If you transmit or provide the GIS Data (or any portion of it) to another user, the GIS Data must include a copy of this disclaimer.
Ordering Instructions These data may be requested from Kristofor Parson, MN.IT via email at
Online LinkageNone available

Section 7 Metadata Reference
Metadata Date 02/06/2019
Contact Person Information Kristofor Parson, Data Specialist
Minnesota Pollution Control Agency
525 S. Lake Ave.
Duluth, MN  55802
Phone: 218-302-6622
Metadata Standard Name Minnesota Geographic Metadata Guidelines
Metadata Standard Version 1.2
Metadata Standard Online Linkage

This page last updated: 02/06/2019
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