Jump to content

Topo maps from the mid 80's


Clowes

Recommended Posts

On a related note... How often do Topo maps really need to be updated? It seems to me it would not be to often since elevation in most areas doesn't change much unless there has been a natural disaster or large scale human interference (construction, strip mining, ect.)

Edited by mpilchfamily
Link to comment

On a related note... How often do Topo maps really need to be updated? It seems to me it would not be to often since elevation in most areas doesn't change much unless there has been a natural disaster or large scale human interference (construction, strip mining, ect.)

 

Many of the topos in the GTA are woefully out of date due to large scale urban sprawl.

 

But you are correct for rural and wilderness areas.

 

The main thing that changes is magnetic declination but topos show how to calculate current declination.

Link to comment

On a related note... How often do Topo maps really need to be updated? It seems to me it would not be to often since elevation in most areas doesn't change much unless there has been a natural disaster or large scale human interference (construction, strip mining, ect.)

 

 

A friend of mine found an old antique gun and it is missing a piece. The general area it was found in has been flooded several times since the find (95 and 04 for sure and maybe some other years too). We would like to be able to compare where the creeks run today in comparison to when the gun was found in the mid 80's as it was found near but not next to a creek.

 

It may not even be a topo map we are looking for, but it may help.

 

Thanks for all your suggestions and if you have more to share, please do.

Link to comment

Ooo, I'm not sure a topo map of the correct date would be accurate enough to help you with that, but it's worth a try I suppose.

 

I have a suspicion they rarely ever update the topo and waterbody info, and that a map from any given date could easily be based on data from decades earlier. I believe they update man-made features a bit more diligently than the natural ones.

 

A few times I've found a cache on one side of the creek, when the topo map in my unit was sure it would've been on the other side, in other words, misplaced creek. But not too often.

 

Good luck!

Link to comment

As a retired Artillery Surveyor I had to rely on using map objects to determine my position on a map, we used Firm Map Detail of a spot that was permanent and identifiable on the map, crossroads were the best to use, and even then they only yeilded a map spot coordinate of about 25 metres accuracy.

we often tried to get it under 15 metres but that depended on the object used.

Most maps in Canada were updated in the late 90s to reflect WGS84 Datum amd even then there is so much new development that makes it hard t get an accurate picture of what is on the ground.

Old maps are great to find those old interesting places that have seemed to have vanished from the map but still there..

 

check here for Alberta map data some of it may be older Large PDF format,, http://www.ags.gov.ab.ca/GIS/download_gis.htm

Link to comment

I am looking for some topo maps from around 1985 for the Southwestern Alberta. Does anyone know how or where I could find them?

 

I am a Geomatics Technician in the Canadian Forces and I use Geogratis very regularly to get maps and other gis data. As the name of the website indicates the data is free, however there is a user aggreement that you must abide by.

 

You will be able to find maps of southern Alberta in there.

 

Good Luck

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...