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Designing data and map for displaying three water quality variables for given well locations

September 06 2007 | 0 comments

I am involved in creating maps for volunteer Mapping and Assessment teams that work with Water
for People. These teams take a GPS reading at a community, then assess the area's water, sanitary and hygienic conditions. The conditions are rated as good, moderate and poor. I symbolize the conditions by creating a pie chart with three equal areas for the water, sanitary and hygienic conditions for each location. I then manually change the color of each section of the pie chart to reflect the assessment rating: good (green), moderate (yellow), bad (red). Using this method, I have to create a separate layer and table for each symbol. Is there a method to create all the symbols in one layer using one table while being able to edit and update the rating color of the conditions in the single table?

Thanks for your help.

Mapping Center Answer:

I don’t know of a way to do what you want with just one layer. There is a sample symbolset on ArcScripts:

http://arcscripts.esri.com/details.asp?dbid=12011

that contains some symbols for doing something like this kind of mapping, though it won’t handle complex cases. The idea would be to use the concentric circles method described in the PDF that is included with the download.

In the long term, since we’ve actually had a number of people ask about this kind of mapping we are going to create a symbol set that would handle more such cases and hopefully have it ready late this year. (added 1/18/08, we're still working on it.)

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