Geodetic Database: Minnesota Department of Transportation (Mn/DOT)

This page last updated: 09/11/2013
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 Department of Transportation (Mn/DOT)
Title Geodetic Database: Minnesota Department of Transportation (Mn/DOT)
Abstract The Geodetic Database contains information on permanent geodetic control marks located in Minnesota or just outside its boundaries. Permanent geodetic control marks are established for the purpose of providing precise horizontal and vertical control positions for the registration of surveying and mapping activities in the local area. Information about the location of an object based on its geodetic location locates that object in a worldwide geographic information system. The marks have unique identification and year established stamped on the monument disk, usually an 89 mm (3.5 inch) diameter brass or aluminum disk. Monuments consist of material (concrete or metal) that is meant to stay in place for 50 to 100 years or more, and have little or no movement due to frost action or activity near the monument. The marks have been established by all levels of government in Minnesota, and they are referenced to the National Geodetic Reference System (NAD 1927, NAD 1983, NGVD 1929, and NAVD 1988). The Federal Government supports monumentation at the state level by providing technical expertise, adjustments of the data, and maintenance of the National Geodetic Reference System through its State Advisor Program.
Purpose To provide geodetic control information in an electronic medium that will allow convenient data access, modification, and distribution. The data stored in the database allows the user to:

1. Create reports on all geodetic control monuments that reside in a specified area (by county, by township, range, or section, by Latitude and Longitude, etc.)

2. Create a computer file of geodetic control mark data

3. Create a file for input in a GIS format
Time Period of Content Date 1998
Currentness Reference Starts with the year the mark was set with history of years that the mark was adjusted and recovered.
Progress Complete
Maintenance and Update Frequency Continuously, mark by mark
Spatial Extent of Data Minnesota
Bounding Coordinates -97.25
-89.48
49.40
43.50
Place Keywords Minnesota
Theme Keywords location, Geodetic, Horizontal Control, Vertical Control, Global Positioning System, GPS, Surveying
Theme Keyword Thesaurus ISO 19115 Topic Category
Access Constraints Contact Distributor
Use Constraints Contact Distributor
Contact Person Information John Barke, Geodetic Engineer
Minnesota Department of Transportation, Office of Land Management
395 John Ireland Boulevard, Mailstop 641
St. Paul, MN  55155
Phone: 651-366-3420
Fax: 651-297-1518
Email: john.barke@state.mn.us
Browse Graphic None available
Associated Data Sets Minnesota Public Land Survey System Control Point Inventory

Section 2 Data Quality
Attribute Accuracy Not applicable
Logical Consistency Not applicable
Completeness State of Minnesota is complete. However, not all control marks in the geodetic database have precise horizontal and vertical positions but nearly all have one or the other. Precise horizontal positions are displayed in three forms:

1. Latitude and Longitude on a spherical coordinate system based on NAD 27 and/or NAD 83 Datums.The NAD 83 has had two adjustments, in 1986 and 1996 and is denoted by NAD 83 (1986) and NAD 83 (1996).

2. X and Y plane coordinates on the Minnesota State Plane Coordinate System, South, Central, or North Zones, based on NAD 27 and/or NAD 83 Datums.

3. X and Y plane coordinates on the Minnesota County Coordinate System based on NAD 83 Datum only.

4. X and Y plane coordinates on the UTM Coordinate System, Zone 15

All elevations are displayed as the mark's height above mean sea level for both the NGVD 29 and the NAVD 88 Datum.
Horizontal Positional Accuracy Varies from +/- 3 seconds to +/- .00001 seconds (100 meters to .001 meter) Latitude/Longitude. The accuracy of each individual horizontal station can be derived from the number of significant digits.
Vertical Positional Accuracy Varies from +/- 3 meters to +/- .001 meter. The accuracy of each individual vertical station can be derived from the Method field in the database.
Lineage HISTORY OF THE GEODETIC DATABASE:

The need for a Geodetic Database available to the local surveying and mapping community has been identified at many levels of local government. Increased uses of the Global Positioning System (GPS) for positioning objects or monuments has generated more requests for geodetic control information. Access to geodetic control information for all levels of government and the private sector fosters a common locational reference system and acceptable accuracy standards for all levels of GIS/LIS activities. The Mn/DOT Geodetic Unit recognized this need in the early Seventies, and work was started to automate the information then.

Computer formatting of this data took place in stages over the past twenty years. The new horizontal datum (NAD 83) was made available in August, 1986, and the new vertical datum (NAVD 88) became available in November, 1991. With the introduction of the new horizontal datum, Mn/DOT provided a ground coordinate system (County Coordinates) that allows the user to compute and map using horizontal ground distances.

The Minnesota High Accuracy Reference Network (HARN) observations resulted in a readjustment of the geodetic network based on the NAD 83 Datum. The HARN observations completed during the period of 1993-1996 using high precision GPS techniques, were adjusted by the National Geodetic Survey in December, 1996. After the observations were adjusted for the HARN, the entire geodetic network in Minnesota will be readjusted, holding the HARN stations fixed. The shifts of the NAD 83 (1986) adjustment compared to the NAD 83 (1996) HARN adjustment are relatively small for mapping purposes (+/- 0.03 ~ 0.70 meters) but significant for geodetic surveys. The source scale is 1:24000 (USGS Quadrangle map) for scaled Latitudes and Longitudes of vertical control marks that have not been positioned by a horizontal control survey.

In January 2002, Mn/DOT began Federal Base Network (FBN) observations. The FBN provides spatial reference control that has some of the most precise accuracies available. FBN observations concluded in February 2002. This survey consisted of 54 stations on a 100 km grid spacing.

In January 2004, Mn/DOT began the Cooperative Base Network (CBN) observations. This survey consisted of 454 stations on a 25 km spacing. Phase 1 observations concluded in May 2004. These observations included stations in Districts 1 and 2. Phase 2 observations began in October 2004 and concluded in May 2005. These observations included stations in Districts 3,4,6,7,8 and Metro Division.

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

Section 4 Coordinate System
Horizontal Coordinate Scheme
Horizontal Datum
Horizontal Units Not applicable

Section 5 Attributes
Overview All of the information contained in the database for each of the control marks will presently fit on an 8.5 x 11 inch page. The Geodetic Database consists of the following fields:

STATION NAME: Designation of the control mark. This is normally the same name that is stamped on the survey monument disk, except for MNDT horizontal marks.

NGS QUAD: NGS 7.5-minute quadrangle designation

STA#: 4-digit station number for horizontal geodetic control marks that are published as part of the National Geodetic Reference System

COUNTY: Name of the county that the control mark is located in

MAP SHT: County Highway Map Sheet Number for the mark's location in the County

INDEX: Control Mark Index Number (for marks with vertical control) that is displayed next to the mark symbol or name on the map sheet

NGS ACRN#: Unique NGS Archival Cross Reference Number which links the Mn/DOT Geodetic Database Record to the NGS Database

1/4: PLS quarter section

SEC: PLS section

TWP: PLS township

RNG: PLS range

LATITUDE: Approximate latitude of the mark for purposes of searching the database by LAT/LONG or for displaying on a map

LONGITUDE: Approximate longitude of the mark for purposes of searching the database by LAT/LONG or for displaying on a map

GPS: Choice field. The $ sign indicates that the mark has been occupied and measured by GPS precise positioning equipment. H indicates that the mark is High Accuracy Reference Network (HARN) station.

USGS QUAD MAP: Name of the 7.5-minute USGS Quadrangle Map that the mark is located in

AGENCY: Initials of the government agency that established the mark

YR-SET: The year that the mark was set

YR-REC: Most recent year that the control mark was recovered

COND: The condition of the monument at the time of last recovery

PHYS: Physical description of the monument material or structure

BRDG#: The Mn/DOT Bridge Number for those marks located on a bridge structure

_ _ _ _: Year that the mark's description was written or updated

STAMPING: The stamping on the actual monument disk or access cover. It does not include the die-cast text.

DESCRIPTION: An abbreviated description of the mark's location

NGVD 29: The National Geodetic Vertical Datum 1929 elevation of the mark

NAVD 88: The North American Vertical Datum 1988 elevation of the mark

ELLIPSOID HEIGHT: The geometrical height of a point above a referenced ellipsoid measured along the normal of the referenced surface

ORDER: The order of the vertical control survey (1st, 2nd, and 3rd) that established the precise elevation of the mark.

METHOD: The method of survey measurement used to compute the elevation

YEAR: The year of the adjustment

REFERENCE: The source of the elevation displayed

GEOID 96 HEIGHT: The difference between the surface of a reference ellipsoid and the geoid. In Minnesota, the geoidal surface is below the ellipsoidal surface, therefore, the height value is negative.

MN ST. PLANE ZONE: The State Plane Coordinate Zone (South, Central, or North) in which the mark is located

SPECIAL COUNTY ZONE: The special county zone in which the mark is located

ST PLANE NAD 27: X COORDINATE

ST PLANE NAD 27: Y COORDINATE

NAD 27: LATITUDE

NAD 27: LONGITUDE

YEAR: The year of the adjustment

REFERENCE: The source of the adjustment for the precise position

ST PLANE NAD 83 (1986): X COORDINATE

ST PLANE NAD 83 (1986): Y COORDINATE

NAD 83 (1986): LATITUDE

NAD 83 (1986): LONGITUDE

YEAR: The year of adjustment

REFERENCE: The source of the adjustment for the precise position

COUNTY: X COORDINATE - based on NAD 83 (1986)

COUNTY: Y COORDINATE - based on NAD 83 (1986)

Free space to allow for comments, etc., pertaining to the coordinates that are displayed

ST PLANE NAD 83 (1996): X COORDINATE - based on the HARN adjustment for Minnesota

ST PLANE NAD 83 (1996): Y COORDINATE - based on the HARN adjustment for Minnesota

NAD 83 (1996): LATITUDE - based on the HARN adjustment for Minnesota

NAD 83 (1996): LONGITUDE - based on the HARN adjustment for Minnesota

YEAR: The year of the adjustment

REFERENCE: The source of the adjustment for the precise position

COUNTY: X COORDINATE - based on NAD 83 (1996) and the HARN adjustment for Minnesota

COUNTY: Y COORDINATE - based on NAD 83 (1996) and the HARN adjustment for Minnesota

Free space to allow for comments, etc., pertaining to the coordinates that are displayed

Date of original entry

Last entry or modification of the record in the Database

The database user name of the person who made the most recent modification of the record in the database
Detailed Citation Mn/DOT Geodetic Unit, Database Documentation, 2000.
Mn/DOT Geodetic Data Sheet Definitions: www.dot.state.mn.us/surveying/Geodetics/Data_Sheet_Definitions.pdf
Table Detail:

Section 6 Distribution
Publisher Minnesota Department of Transportation (Mn/DOT)
Publication Date Unknown
Contact Person Information John Barke, Geodetic Engineer
Minnesota Department of Transportation, Office of Land Management
395 John Ireland Boulevard, Mailstop 641
St. Paul, MN  55155
Phone: 651-366-3420
Fax: 651-297-1518
Email: john.barke@state.mn.us
Distributor's Data Set Identifier geodetic
Distribution Liability The Minnesota Department of Transportation makes no representation or warranties, express or implied, with respect to the reuse of data provided herewith, regardless of its format or the means of its transmission. There is no guarantee or representation to the user as to the accuracy, currency, suitability, or reliability of this data for any purpose. The user accepts the data 'as is', and assumes all risks associated with its use. By accepting this data, the user agrees not to transmit this data or provide access to it or any part of it to another party unless the user shall include with the data a copy of this disclaimer. The Minnesota Department of Transportation assumes no responsibility for actual or consequential damage incurred as a result of any user's reliance on this data.
Ordering Instructions Go to 'Online Linkage' to access the Geodetic Database, the Interactive Geodetic Monument Viewer, and the Geodetic Feature Service.

Use the Geodetic Database to view or download County Data Sheets, County Map Sheets, County Index Sheets, and Station Photos. For further information, contact distributor.
Online Linkage I AGREE to the notice in "Distribution Liability" above. Clicking to agree will either begin the download process or link to download information. See "Ordering Instructions" above for details.

Section 7 Metadata Reference
Metadata Date 09/11/2013
Contact Person Information John Barke, Geodetic Engineer
Minnesota Department of Transportation, Office of Land Management
395 John Ireland Boulevard, Mailstop 641
St. Paul, MN  55155
Phone: 651-366-3420
Fax: 651-297-1518
Email: john.barke@state.mn.us
Metadata Standard Name Minnesota Geographic Metadata Guidelines
Metadata Standard Version 1.2
Metadata Standard Online Linkage http://www.mngeo.state.mn.us/committee/standards/mgmg/metadata.htm


This page last updated: 09/11/2013
Go back to top