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Our task is to draw a lake with a solid outer perimeter line and no lines between internal wetlands, shoals and shallows? 'Tis a relatively straightforward process with Arcinfo coverages and Regions, but alas, that is no longer a viable option for us, the datasets we use now are too large and the lack coverage editing ability in Arcmap crucial. Can cartographic representation solve our dilemma? Is it possible to create something like the below without resorting to creating (and managing) duplicating, or triplicating, geometries whose sole purpose is better looking maps?

comparing rendering of FCs with Regions (click through for more detail)

With a feature class: Boundary between river and lake is visible. Keeping them as distinct polygons in one feature class allows a name attribute (the river and laker differ). Elsewhere the heavy line implies a sharp boundary between lake and shallows/intermittent lake, however the actual edge is indeterminate, fluctuating with seasons and high-low water cycles. The line should be implied rather than drawn.

With regions: One geometry, multiple attribute tables, multiple representations.

  • Outer perimeter (ordinary high water mark) is cleanly delineated
  • No apparent division between lake and river, but they still know which is which
  • Shallow/intermittent waters are symbolized appropriately, with river shallows distinguished from lake shallows.

See here for a map package simulation of what we're trying to achieve and the source arcinfo region coverage from which it is built.

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    Have you tried representations? not on my computer now so can't try this my self right now... one crude solution I can think of (not duplicating geometry but having 2 layers in the TOC) Assuming all the features are in one feature class: Top layer symbolized by category with no outline on any of the features, bottom layer symbolized as one feature with a thick outline. This way the thick outline will surround all features but not the adjacent features. I will try this with representations tomorrow
    – Jakub Sisak GeoGraphics
    Commented Apr 15, 2011 at 1:34
  • related thread: gis.stackexchange.com/questions/747/…
    – Kirk Kuykendall
    Commented Apr 15, 2011 at 14:40

3 Answers 3

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I cross posted this question on Esri's Ask A Cartographer site. They pointed me to a mostly-suitable workaround: use Symbol Level drawing in general and Dissolving polygon boundaries using symbol level drawing in particular. Likely what Craig was pointing at earlier in his answer. I've seen the dialogs and help topics before but hadn't dug into them because the examples are about cased lines and I didn't understand how the same principles could be applied to polygons. With the v10 help they've greatly expanded the examples and procedures. Although written for a v10 audience it should help v9.x users as well as it hasn't changed that much.

I did finally get Symbol Levels to work with our data in situ (no duplicate feature classes created, no attributes added). There are few inconsistencies in the symbol level interface which add confusion, which I'll mention here (a.k.a. "watch for submerged rocks" and "here be dragons"):

  • Boundaries don't dissolve when marker or picture fills are used, only plain and gradient fills work
  • Sometimes editing a symbol causes it to jump to the top of stack (under "Advanced > Symbol Levels") and it's join/merge state change to unchecked.
  • Sometimes the advanced settings won't "take", try changing the stack order and various applications of enable/disable join/merge.
  • After enabling Symbol Levels Occasionally the "apply color ramp" step (#17) doesn't work at all. The symbols stick with what is defined in the upper most Edit Symbol dialog. An Arcmap reboot seems to cure it.

A workaround for using marker/picture fills, dissolving all internal boundaries, and drawing outermost perimeter of all objects ("ordinary high water mark" in the sample data (linked to in Q)) is to:

  • add the layer a second time in the TOC, below the marker/pic fill layer,
  • Use "Single Symbol", plain fill, enable Symbol Levels, do the same double layer trick as above under advanced symbol properties
  • and enable both Join and Merge checkboxes (another bug here: sometimes the []Merge box is not enabled until after you go to advanced symbol properties editor.)

Develop the habit of always doublechecking the stack order and the join merge properties. Just because you told it to do/not-do X doesn't mean it actually remembered.

So in summary,for cartographic purposes Symbol Levels with join & merge properties is a workable if quirky analog for Arcinfo Regions. For analytical purposes like "query surface area of ordinary high water" you'll still need to do some geoprocessing and generate duplicate data.

(UPDATE) It is possible after all to use picture symbols, symbol levels, and a single ToC layer. You set your tongue to the right, just so, stand on one leg (doesn't matter which), and face the moon. From here get a map package illustrating two working methods (Lake-cartography-symb-levels - update.mpk).

illustration of the 3 approaches

see full size image

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  • important note: the Join and Merge options will only be clickable after the symbol has more than one layer, see Symbol Property Editor.
    – matt wilkie
    Commented May 8, 2012 at 18:50
  • Please note that while this is the accepted answer, as in it's the best that can be done with the tools currently in vogue, it's not the most acceptable answer, which would be modern Regions reboot. ;-)
    – matt wilkie
    Commented Dec 17, 2015 at 6:26
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The below capture is using the method i described in my comment. (not representation - both layers referencing the same data)

Tried to achieve this with representations in one layer but could not do it. Tried to generate just an outline with cartographic representation so that it may be used as an overlay but also could not do it. (Cartographic representations were a big reason I upgraded to ArcEditor but so far I've used them very little as it is not as powerful a tool as I initially anticipated.) enter image description here

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  • Good answer. While simple, creating multiple layer files that reference the same data layer, and simply applying the appropriate definition query to each can often be the quickest and simplest method of displaying this type of data.
    – RyanKDalton
    Commented Apr 15, 2011 at 15:40
  • The same layer loaded multiple times with different symbology is a technique we've used in the past for other things, but it doesn't work here because even with definition queries the outermost perimeter (ordinary high water) can not be displayed without also drawing internal boundaries. Please see the example dateset now linked from the post.
    – matt wilkie
    Commented Apr 18, 2011 at 17:02
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Convert your region polygons to overlapping features. You can then symbolize them however you want based on attribute. Drawing order can be controlled via symbol level drawing so that the wetlands always draw on top. Use topology rules to ensure the multiple polygons are kept in sync.

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  • I don't see how overlapping polygons and topology can maintain the attribute distinction between lake and river and yet not draw a boundary line betwixt. Perhaps I just don't understand what you mean. Maybe you could demonstrate with the sample data now linked to from the main question?
    – matt wilkie
    Commented Apr 18, 2011 at 17:07

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