Navigation/Maps
From PCSAR
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Topographic Maps
The best available maps PCSAR has for the back country are topographic maps produced by Canadian Government.
These are called
- Formal Name: Canadian National Topographic System 1:50,000
- Military Designation: Series A 741
- Common Name: Canadian Topo Map
Advantages
- They are detailed
- They show the shape of the land
- They provide a UTM grid
- They cover all areas PCSAR is likely to respond to (and most of Canada)
- They are produced as quality map sheets
Disadvantages
- They are dated. Depending on the map, they were last updated in the 1970s. Which means man-made features such as roads, buildings, pipelines, cutlines may have been added.
- Map Datum is typically NAD 27. Most other sources are NAD 83/WGS 84.
- Elevation is typically shown in feet, rather than meters.
Purchasing Cautions
The maps have been updated in a series of numbered "editions", shown in the upper right corner. The latest edition is usually Edition 2 or Edition 3. It's unusual to find an outdated edition being sold.
For a few locations, especially national parks, a new edition has been created where the map elevations have been converted to metric. These are typically Edition 4. Unfortunately when redrawing the contour lines, they have been computer interpolated, rather than replotted from the original (or new) aerial photographs. As a result there is less detail when examining the shape of the land. These maps have also been converted to WGS 84 (a good thing). In total, having the pre-metric earlier edition, if you can find it, would probably be better.
The Government of Canada no longer prints these maps itself. They have allowed private companies to print them. As a result the quality is uneven. Check for:
- Registration issues. We've found some maps where the blue, green, red or black ink is shifted to a different position relative to the other inks. As a result features are shown in the wrong position.
- Single sided. The maps should have a key of symbols (legend) on the back side. Each map has its own legend including any unusual symbols on that map.
- Folded. Maps may be sold folded instead of rolled. The folding will make it harder to use the maps on a map table. If you're going to use the map in the field instead, you'll probably want the creases in different places, and the original creases will make handling the map difficult.
Sources
- downloadable topo maps
- 82G/8 (Beaver Mines)
