20K Base Features
The 1:20 000 Base Features is a GIS spatial database product to which other natural resource and land management information can be related.
Base Features includes over 60 layers of topographic information separated into 5 major themes (Access, Hydrography, Geo Admin, Contours, and ATS). Updating projects are ongoing at the Government of Alberta.
The Base Feature coverage includes the entire province (3030 files) and is available by the National Topographic System (NTS) grid and full provincial layers. A 1:20 000 NTS map sheet covers the area of approximately 2.5 townships.
Base Feature topographic mapping is available at no cost under the Open Data License and are accessible from the download tab.
Multiple formats, projections and merged options are available for a minimum service fee of $50
Alberta Township System - Arcs and polygons with extents for quarter sections and road allowances. Based on the V4.1 (March 2005) ATS Coordinate file
Hydrography - The extent of land covered by intermittent or permanent water bodies or watercourses. Includes direction of flow
Access - The location and nature of features that can be used to gain vehicular access to land and resources and to dispositions related to surface activities
Geo-Administrative Areas - Land areas that have explicitly defined boundaries, established by legislation or by an agency to manage or administer land use
Contour Linework - 10m (20m in mountainous regions) contours, consisting of arcs and index annotation, will combine to create a seamless cartographic theme to define Alberta’s topography
The Base Features open dataset is a NAD83 GIS (SHP) product, with an accuracy of +/- 5 meters for most of the province. Individual mapsheets are in a 10TM (AEP Resource projection or EPSG 3401 projection), with a reference meridian of 115. Full provincial layers are in geographic coordinates.
Individual mapsheets are available in UTM projections with the reference meridians of 111 degrees (Zone 12) and 117 degrees (Zone 11) and as geographic coordinates. MicroStation Design Files (DGN), AutoCad (DWG) format, and merged mapsheets in SHP format can be requested from the Order Desk.
It is important to note Base Features is intended to be a GIS product. CAD users will find that text (labels) and other attribute information is lost after translation to CAD formats. CAD users are encouraged to consider the 1:20 000 Historic Base dataset as an alternative.