1:20 000 Digital Elevation Models (DEM)
A Digital Elevation Model (DEM) is a digital representation of ground surface topology or relief. AltaLIS DEM contains three dimensional spatial ground elevation masspoints, which are spot elevation points, hard breaklines, which include cliffs, ridges, peaks, and bodies of standing water, and soft breaklines include all other hydrographic features.
These coordinate files can be manipulated and imported into external software for the generation of 3D renderings, and provide excellent detail for 3D surface analysis, modeling water flow, or planning road, pipeline, and well locations. The 1:20 000 DEM is available by the National Topographic System (NTS) grid, and each map sheet covers approximately 2.5 townships in area.
The 1:20 000 DEM product 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
Provincial GRID format delivered on an external drive is $600
Three-dimensional coordinate data referenced to zero (0.0) at mean sea level, derived from Photogrametrically compiled Digital Elevation Data, and compiled with 1:60 000 scale air photography during the Provincial Base Mapping Program. Each mapsheets consist of 3 individual (ASCII) files containing the masspoints and hard & soft breaklines.
The open 1:20 000 DEM is available in an ASCII format with a 10TM projection (reference meridian of 115, 500000 Easting), also referred to as “NAD_1983_10TM_AEP_Forest”.
Datum is NAD83, with an absolute accuracy determined by Alberta Survey Control Markers, and relative accuracy (depending on terrain) of +/- 5 meters for X,Y & Z.
Federal Lands- Jasper and Banff National Parks: 90% of points are within 20 meters, and Wood Buffalo National Park: 90% of points are within 25 meters.
GIS (SHP) format for individual map sheets, contiguous cuts (up to provincial coverage) in ESRI (GRID) format, and ASCII format with a UTM (reference meridians of 111 degrees (Zone 12) and 117 degrees (Zone 11)) projection can be requested from the Order Desk.