Always ask for the source files, not just the final product

I’ve been asked to make a map of the final admin plan for Dàadzàii Vàn (Summit-Bell) Territorial Park for Cabinet submission. So an important map to do well.

The substantive record from Canada Land Survey office is 108175 CLSR YT and illustrates how hard it is to get policy right. That map/plan is a scan, so all the line work is slightly fuzzy, and inside the pdf a single flattened bitmap. Contrast that with the preliminary plan we were provided last year which consists of vectors with real numbers and points, and layers which can be turned on and off. An inspection shows there are differences between preliminary and final plans.

Additionally, with the preliminary plan we were also provided the CAD vector file, which can be ingested into any professional mapping software directly. It holds the individual feature objects, actual real world coordinates, etc. etc. THIS should be the actual substantive record, however it is not part of the registry system and is not available to anyone else who needs to build on or re-use this work.

In order for me to build a map using the authoritative line work I need to track down the surveying company, if it still exists, and ask them for their real lines, if they’re willing to give them (or sell), if they can be bothered to find them. When this avenue doesn’t work, and it often doesn’t, I create a facsimile which will be different from the source. Repeat for everyone else who wants to use it and who all have varying degrees of skill and attention to appropriate detail. It’s a mess, and sadly unnecessary. All that’s needed is to have the signed scan AND the source vectors part of the official record.

Substantive record, a scanned image:

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Preliminary plan with most line work turned on:

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Preliminary plan with most relevant lines isolated:

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CAD Drawing – individual feature objects, actual real world coordinates, etc. etc. THIS should be the actual substantive record, however it is not part of the registry system.

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Signatures, the reason why scans are considered the substantive record. A logical reason (and really needed), but actually quite a big mistake. There are ways (now) to digitally certify something correct. At the very least have the signed scan AND the source vector line work in the registry system.

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(In case you’re wondering, in this instance the surveyor Paul Burbidge responded with source work in a couple hours, so I wasn’t slowed that much. He also included a related source work for a related survey I’m going to need soon but didn’t think to ask for at the time. Thank you Paul!)

This story uses a survey plan as a “don’t do that!” example. However yesterday I also fielded similar didn’t-have-to-be-this-hard request for someone who wanted to print a very simple poster, but they used super-compressed jpeg for source because they didn’t have (or know about needing) the original vector artwork. A 10 minute job turned into multi-day go-hire-a-contractor quest. Sad, because it’s so avoidable, and so common, but people just don’t know.

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Moral of the story: always ask for and keep the source files, not just the final product.

One comment

  • To get the CAD or GIS files of a survey plan go through Canada Lands digital Cadastral Data at: https://www.nrcan.gc.ca/data-canada-lands-surveys/11092#CLdata

    The scanned plans are still the substantive record so the cadastal are prefaced with scary warning words of “By using this data, it is important to understand and accept that the data is not to be used for defining boundaries. Administrative decisions should be based on legal documents and legal survey plans.”. However this is as close to authoritative as we’ll get for the foreseeable future.

    Also the ftp site gives you all of a UTM zone at a time so you have to do leg work to get the right zone, and then discard what you do not want. Still much better than digitizing from the scanned plan on your own though.

    Thank you to Elden Pfieffer, Senior Surveyor-GIS at Yukon Regional Office of NRCAN for pointing me to this download option.

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