Data format: Shapefile
File or table name: north_twp2
Coordinate system: Universal Transverse Mercator
Theme keywords: Theoretical, Manitoba Reference Grid, North
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Data format: Shapefile File or table name: north_twp2 Coordinate system: Universal Transverse Mercator Theme keywords: Theoretical, Manitoba Reference Grid, North |
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Abstract:
The Northern Manitoba Theoretical Reference Grid is a computed grid. It is governed by the Third System of Survey under which all road allowances are 66 feet in width. These road allowances occur every mile east-west but only every second mile north- south. Horizontal (MANOR) survey control adjustments were completed for all surveyed baselines and meridians based on measurements shown on Director of Surveys Plans or other records available within the office of the Director of Surveys. These adjustments were constrained to the most accurate federal and provincial geodetic survey control available at the time of the computations. In northern Manitoba this control was predominantly either ISS or Doppler technology based. |
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Metadata elements shown with blue text are defined in the Federal Geographic Data Committee's (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM). Elements shown with green text are defined in the ESRI Profile of the CSDGM. Elements shown with a green asterisk (*) will be automatically updated by ArcCatalog. ArcCatalog adds hints indicating which FGDC elements are mandatory; these are shown with gray text.
The Northern Manitoba Theoretical Reference Grid is a computed grid. It is governed by the Third System of Survey under which all road allowances are 66 feet in width. These road allowances occur every mile east-west but only every second mile north- south. Horizontal (MANOR) survey control adjustments were completed for all surveyed baselines and meridians based on measurements shown on Director of Surveys Plans or other records available within the office of the Director of Surveys. These adjustments were constrained to the most accurate federal and provincial geodetic survey control available at the time of the computations. In northern Manitoba this control was predominantly either ISS or Doppler technology based.
The Northern Manitoba Theoretical Reference Grid has been topologically structured to the quarter-section level. Each quarter-section polygon is a spatially referenced entity with a unique 9 digit parcel identification number or PIN. As attribute data each quarter-section polygon has a DLS key in standard format -section/township/range/meridian. As such it provides an excellent GIS support tool for users who wish to relate tabular data or spatially referenced land parcel data to a theoretical DLS fabric.
The theoretical grid covers approximately townships 35 to 127 north-south and ranges 1-30 Wpm, ranges 1-24 Epm and ranges 1-31 E2ME east-west. There is additional coverage east of Lake Winnipeg between townships 19 to 34, ranges 7 to 17 Epm.
publication date
Data is subject to prescribed terms and conditions of use available at time of data acquisition from the data source. This dataset is a generalized map representation of property boundaries as shown on registered survey plans and has been mathematically adjusted or manipulated. As such it must not be interpreted by the user as defining the true location of any parcel's boundaries on the ground,nor its true size and area. Annotation shown on these cadastral products is intended as information only and is subject to human error. Any misuse or mis-interpretation of displayed parcel information, dimensions or otherwise, is at the user's own risk.
1007 Century St.
The estimated accuracy of the grid is plus or minus 100 metres. However this accuracy fluctuates throughout the grid depending on the density of the geodetic control available at the time of computations and the accuracy of the governing meridian and baseline surveys on which the computations were based. Some of the older original baseline surveys were done using baseline transit and chain. The Hudson Bay shoreline used in the product comes from the Branch's 1:500,000 topographical base map.
The northern Manitoba Theoretical Township/Quarter-Section grid was developed to meet general DLS parcel referencing needs for Northern Manitoba. It was produced intermittently on an ad hoc basis over some 8 years and has only recently undergone rigorous topological structuring. Although the grid topology has been checked there has been no quality control done on polygon annotation due to the large number of polygons involved (800,000 or so). The mathematical solution used in the grid's production was not a unique solution as professional judgement had to be used as to how to deal with any misclosures which became evident when undertaking the MANOR adjustments of the baseline and meridian surveys on which the grid is based. This is particularly true when computing theoretical township positions in the Lake Winnipeg and Lake Winnipegosis areas which contain some of the province's weaker baseline surveys. Proportioning of the misclosures was a common solution but not used in every instance as intermittent retracement surveys often impacted decision making and the final grid layout. A known weakness of the grid is the fact that it has been perpetuated through several of the surveyed townships in Northern Manitoba. This is particularly true in the area around The Pas (Tps 50 to 60) and along the predominant railway system which stretches from Clearwater Park to Gillam to Thompson to Churchill. Time and resources did not permit the undertaking of the labor intensive computations required to derive graphical representations of each surveyed township in northern Manitoba. End users are cautioned to respect the existence of these surveyed townships and that use of this grid for parcel referencing in these areas should be undertaken only as a last resort.
A specialized software program was written to determine mathematically the coordinate positions for the four corners of each standard theoretical township (6 miles wide by 6 miles deep) northerly and southerly from each surveyed baseline accommodating for the proper widths of road allowances at correction lines. The interior sections for each theoretical township were created by mathematically subdividing into 36 units each computed theoretical township block. Graphics software was used to connect the computed points and output a graphical representation of each theoretical township together with a standard DLS key for each theoretical township and each of its interior sections. This was the original grid. It has since been value added in that it has been further subdivided and topologically structured to the quarter-section level. Unique 9 digit parcel identification numbers or PINS have been assigned to each theoretical quarter-section parcel to facilitate use of the graphics grid with tabular data in a relational database. The PIN serves as the primary linkage mechanism between the two. A graphical change in the product was made by showing all road allowances as double width lines rather than single lines.
1007 Century St.
Due to the large size of he Northern Manitoba Theoretical Reference Grid, it has been sepertaed into 27 maptiles. Maptiles 1 through 27 were downloaded from the Manitoba Land Initiative [MLI] website, and appended together using the ArcGIS geoprocessing wizard located in ArcToolbox. The layer was then checked to make sure of no overlap with the Southern Reference Grid.
Box 25 - 200 Saulteaux Cres.
Noticed duplicate records for most quarter sections. Used ET Geowizard to remove duplicates.
Box 11 - 200 Saulteaux Cres
Metadata imported.
Dataset copied.
Metadata imported.
Internal feature number.
ESRI
Feature geometry.
ESRI
Unique 9 digit parcel identification number.
Quarter Section
Section
Township
Range
Meridian
Area of each parcel
The theoretical reference grid consists of a series of topologically structured Mastertiles. A Mastertile is 4 townships deep (24 miles) and extends province wide from the Manitoba/Saskatchewan boundary to the Manitoba/Ontario boundary. There are presently 27 Mastertiles in the grid with Mastertile 1 being the most northerly full 4 townships in the province and the Mastertile numbers increasing by one for each 4 townships one proceeds southwards.
200 Saulteaux Cres
e-mail preferred
Use at own risk. Data accepted as is. Product is subject to periodic changes
The Manitoba Theoretical Reference Grid is available in two common spatial referencing data formats - AutoCAD DXF or ESRI Shapefile.
CONTACT MLI Data Warehouse custodian - Mr. Al Dakin. adakin@gov.mb.ca Please provide a description of product desired - extent of area - required data format.
Box 25 - 200 Saulteaux Cres.
Basic Metadata developed by Malcolm Finnie - Geomatics Branch.