In general, attributes are believed to be accurate.  In most cases, if there is doubt about the accuracy of an attribute, it is left blank.  Most of the attributes are supplied by the source data systems: Equis and Minnesota Pollution Control Agency's (MPCA) regulatory database.

This data set contains all known Minnesota Pollution Control Agency (MPCA) lake, stream chemistry and stream biological monitoring stations.  The completeness of the USGS monitoring stations is unknown.  The National Pollutant Discharge Elimination System (NPDES) discharge station (station_type = "DISCHARGE") dataset is not complete because MPCA has not obtained location data for all of the permitted dischargers.  As of 8/15/2003, 290 of 1704 discharge stations with discharge monitoring report data were not included in the data set.

Due to the variety of sources for this data set, positional accuracy varies by station type:

Station Type = STREAM or LAKE: For stations where station_detail_source = STORET, most of the station locations have been created using ArcView and United States Geological Survey (USGS) 7.5 minute quad sheets as the base map.  These station locations are generally within 100 yards of their actual locations and are typically shown as being on the correct water body.  For stations where station_detail_source is "LEGACY", most of the locations were generated by organizations other than MPCA using unknown methods with unknown accuracy.  Inspection has shown that accuracy varies widely, with some errors of 100s of kilometers noted, and numerous instances of stations located on incorrect water bodies.  Some effort has been made to correct these locations, and most of the gross errors have been identified and corrected, but in general, this group of station locations should be used with caution.

Station Type = "DISCHARGE":  The accuracy of locations of this group of stations also varies widely.  The majority of them have been located using ArcView with 7.5 minute quads as the basemap, and using National Pollutant Discharge Elimination System (NPDES) permit location descriptions and permittee submitted maps as the source of the locations.  A minority of the locations were supplied by permittees as lat/long coordinates and are of unknown accuracy.  In general, inspections show that most of the station locations are sufficient to determine which water body the discharge drains to, but may be more than 100 yards away from the actual discharge location.

Station_type = "USGS":  This locational data was provided by the United States Geological Survey (USGS) and positional accuracy has not been evaluated.

Station_type  = "BIOLOGICAL":  This dataset was developed using a consistent process of creating locations using ArcView and the accuracy is believed to generally be well within 100 meters of the actual sampling location.

Station_type = LAKE or STREAM, Station_detail_source = EQUIS:  The attributes and locations for these stations were obtained from the Minnesota Pollution Control Agency's (MPCA) local instance of STORET.  The resulting table of data was converted to an ArcSDE feature class using ArcMap.  This data set is updated regularly by obtaining new station data from EQUISand loading it into the feature class.

Station_type = LAKE or STREAM, Station_detail_source = LEGACY:  The attributes and locations for these stations were obtained from MPCA's copy of the US Environmental Protection Agency's "Old" STORET database, also called Legacy Storet.  This data set was reviewed to remove stations that were migrated to "modernized" STORET (now known as EQUIS). It was then converted to an ArcSDE feature class and then loaded into the combined Station feature class.  The locations of this data set were visually checked to ensure that they were on or near the water body that is described in the attributes.

Station type = BIOLOGICAL:  This dataset was extracted from the MPCA's biological monitoring Access database , converted from x,y data to an ArcSDE feature class in ArcMap and loaded into the Station feature class using ArcCatalog.

Station Type = DISCHARGE:  The attributes for this dataset were extracted from MPCA's Water Quality DELTA database system, and merged with a station location shapefile that was created in ArcView using National Pollutant Discharge Elimination System (NPDES) permit data to determine station location.  In some cases the station was not present in the shapefile, but an x, y coordinate had been provided by the permittee and was stored in DELTA.  These sources were combined and the dataset was loaded into the Station feature class.

For all of the above station types, the attributes FIRST_SAMPLING_YEAR and LATEST_SAMPLING_YEAR are periodically updated by an oracle database script to reflect the current monitoring data associated with the stations.

Station_type = USGS:  United States Geological Survey (USGS) stations and their locations were received directly from USGS staff and added to this data set using ArcCatalog.

The base data for this data set is stored as an SDE feature class and is converted to shapefile for distribution.

Dataset copied.

Metadata imported.

Name, ID, type and location of surface water monitoring stations, including the waterbody they are on, the USGS Hydrologic Unit they are within and the county they are within.

Name and ID Code of Organizations that submit surface water monitoring data to MPCA,

Date monitoring station was established.

Note that in the shape file format of this data set, these attribute names are truncated to the first 10 characters.

Entity Name & Definition

STATION_ID: A unique system identifier for the station.  Usually this is a concatenation of the ORG_ID and the ID_CODE separated by an underscore.

ORG_ID:  A system code used to identify the organization that is responsible for the data.

ORGANIZATION:  The name of the organization associated with the ORG_ID.

ID_CODE	:  The originating organization's unique identifier for the station.

STATION_NAME:  The name of the monitoring station

STATION_TYPE:  The type of monitoring station: biological, discharge, lake, stream, USGS

ESTAB_DATE:  Date the monitoring station was established.

WATERBODY_NAME:  Name of the waterbody the station is located on.

HYDROLOGIC_UNIT_CODE:	 The 8-digit number that identifies the Hydrologic Unit that the station is located in.   Hydrologic Unit Code = "HUC"

HUC	     Hydrologic Unit Name
04010101     Lake Superior (North)
04010102     Lake Superior (South)
04010201     St. Louis River
04010202     Cloquet River
04010301     Nemadji River
07010101     Mississippi River (Headwaters-Lake Winnibigoshish)
07010102     Leech Lake River
07010103     Mississippi River (Grand Rapids)
07010104     Mississippi River (Brainerd)
07010105     Pine River
07010106     Crow Wing River
07010107     Redeye River (Leaf River)
07010108     Long Prairie River
07010201     Mississippi River (Sartell)
07010202     Sauk River
07010203     Mississippi River (St. Cloud)
07010204     North Fork Crow River
07010205     South Fork Crow River
07010206     Mississippi River (Twin Cities)
07010207     Rum River
07020001     Minnesota River (Headwaters)
07020002     Pomme de Terre River
07020003     Lac Qui Parle River
07020004     Minnesota River (Granite Falls)
07020005     Chippewa River
07020006     Redwood River
07020007     Minnesota River (Mankato)
07020008     Cottonwood River
07020009     Blue Earth River
07020010     Watonwan River
07020011     Le Sueur River
07020012     Minnesota River (Shakopee)
07030001     St. Croix River (Upper)
07030003     Kettle River
07030004     Snake River
07030005     St. Croix River (Stillwater)
07040001     Mississippi River and Lake Pepin (Red Wing)
07040002     Cannon River
07040003     Mississippi River (Winona)
07040004     Zumbro River
07040006     Mississippi River (La Crescent)
07040008     Root River
07060001     Mississippi River (Reno)
07060002     Upper Iowa River
07060002     Upper Iowa River
07060002     Upper Iowa River
07080102     Wapsipinicon River
07080201     Cedar River
07080202     Shell Rock River
07080203     Winnebago River (Lime Creek)
07100001     West Fork Des Moines River (Headwaters)
07100002     West Fork Des Moines River (Lower)
07100003     East Fork Des Moines River
09020101     Bois De Sioux River
09020102     Mustinka River
09020103     Otter Tail River
09020104     Red River of the North (Headwaters)
09020106     Buffalo River
09020107     Marsh River
09020108     Wild Rice River
09020301     Sandhill River
09020302     Upper and Lower Red Lake
09020303     Red Lake River
09020304     Thief River
09020305     Clearwater River
09020306     Grand Marais Creek (Red River of the North)
09020309     Snake River
09020311     Tamarac River (Red River of the North)
09020312     Two Rivers
09020314     Roseau River
09030001     Rainy River
09030002     Vermilion River
09030003     Rainy River (Rainy Lake)
09030004     Rainy River (Manitou)
09030005     Little Fork River
09030006     Big Fork River
09030007     Rapid River
09030008     Rainy River (Baudette)
09030009     Lake of the Woods
10170202     Big Sioux River (Medary Creek)
10170203     Big Sioux River (Pipestone)
10170204     Rock River
10230003     Little Sioux River
10710108     Long Prairie River

ASSESSMENT_UNIT_ID:  The Assessment Unit ID of section of water on which  the station is located.  This number is assigned by the MPCA. 

DESCRIPTION:  A text description of the station location.

STATION_DETAIL_SOURCE:  The source database for the station:  Legacy STORET, STORET, USGS or MPCA's WQ_DELTA database.

COUNTY_FIP:  The FIPS code for the County that the station is located in.  See http://www.epa.gov/enviro/html/codes/mn.html for the FIPS code definitions.

FIRST_SAMPLE_YEAR:  Year of the first sampling at this station.

LATEST_SAMPLING_YEAR:	 Year of most recent sampling at this station.

For data or maps created by the Minnesota Pollution Control Agency and delivered online or by physical media.

    Limitations: Although extensive effort has been made to produce error-free and complete data, all geographic information has limitations due to the scale, resolution, date and interpretation of the original source materials. Users should consult available data documentation (metadata) for this particular data to determine limitations and the precision to which the data depict distance, direction, location or other geographic characteristics. Data may be subject to change without prior notification.
    No warranty: Data is provided "as is," without any warranty whatsoever, including but not limited to any warranty as to performance, merchantability or fitness for any particular purpose.
    Liability: The entire risk as to the results of the use of this data is assumed by the user. The MPCA is not responsible for any interpretation or conclusions made by those who acquire or use it. The MPCA shall not be liable for any direct, indirect, special, incidental, compensatory or consequential damages or third-party claims resulting from the use of this data, even if the MPCA has been advised of the possibility of such potential loss or damage. In states that do not allow the exclusion or limitation of incidental or consequential damages, this data may not be used.
    Redistribution conditions: In obtaining this data from the MPCA, it is understood that individuals or organizations have the right to use it for any internal purpose. If data is modified, changes should be documented in a metadata record that should accompany all redistributed data. If data is transmitted or provided in any form to another user, the data should be accompanied by a copy of this disclaimer and all documentation provided with the original data set, including the full metadata record.
    Data delivered on electronic media: If data has been requested from the MPCA on magnetic media, CD or any other physical media, the MPCA will deliver it in the computer-readable format agreed upon with the requestor. The MPCA will reissue data if it is unreadable by correctly adjusted computer input devices or when the media is delivered in a damaged condition. Requests for reissue of this digital data product must be made within 30 days of the date shipped from the MPCA.

Downloadable in shapefile format from the Minnesota Pollution Control Agency's ftp site at the following address:  ftp://files.pca.state.mn.us/pub/spatialdata/eda_wqstations.zip