Contours - meters or feet

[PamBrangan]

Has anyone developed the contours in meters?  When we attending the training we were told to use meters not feet, however all of the guidance and indexing is in feet.  We have generated our contours in meters and are now struggling with the indexing.  I think it would be a lot easier to accomplish if we had an indexing example that was meters.

Thanks.
Pam

[RyanCoghlin]

Hi Pam,

I've made a few community maps for cities in Canada so all our contour data is in meters. It won't really matter what units your contours are in as long as you adjust the Contour Index tool and the contour layers in the map document accordingly.

For instance, if you have 5 meter contours you might set the Contour Index tool parameters as follows:
[INDENT]INDEX1: 10
INDEX2: 25
INDEX3: 50
INDEX4: 100
INDEX5: 200[/INDENT]

Then with the initial setup of the template at 1:1K and 1:2K levels, 10 meter intervals will be shown as index contours and 5 meters in between as intermediate contours.

At the 4K and 9K levels, index contours are at 25 meter intervals and everything in between is intermediate.

Hope this helps.
Ryan C

[PamBrangan]

Hi Ryan - yest that helps put things straight in my head, thanks!
We generated .5 meter contours, but that seems a bit too dense.  What interval did you use - 5 meters?  Did you use the same for all of the places you've mapped?

thanks again.
Pam

[RyanCoghlin]

The cities that I've done have always provided me with contours so I could skip the step of actually generating them. The interval you'll want will depend on the topography of whatever city you're mapping, but 1 meter contours are a good starting point. Then, set:

INDEX1: 5
INDEX2: 10

Then I'd recommend adding a definition query to the contour layers at 1:4.5K and 1:9K so you only show 5 meter increments and it's not too cluttered:
[INDENT]"INDEX1" = 1[/INDENT]

If you zoom in to the Toronto Community map on ArcGIS.com, that's basically how things were done there.

Ryan C

[ArthurCrawford]

Hi,

I wrote the tool and all I would change is that the Index contour is usually every 4th or 5th contour (as described in Eduard Imhof's Cartographic Relief Representation).   If you have 5m contours (1k or 2k), then 25m would be your index.   If you have 10meters contour interval, your index contour would be at 50m (4k or 9k scales).   You don't want to be too heavy with your contours and this can be adjusted for different areas of terrain depend on the community you are in.   We recently did all of Spain at 5m contours and then used the 10m intervals with 50m indexes at 9k and 18k, etc.  Attached is an example of contours symbolized correctly for the index at that scale.

Thanks,

Arthur Crawford
ESRI St. Louis