Archive for April, 2011

Using a User-created Depiction Interaction Rule to Aid in Tornado Damage Assessment

For our Depiction of the Week, we have a guest post from Ric Skinner, GISP, a Depiction Preferred Consultant.

I needed a simple way to do a damage estimate of a tornado path through a town for the Formidable Footprint Tornado tabletop exercise which will be staged on Saturday April 30. After placing a User-defined Shape on my depiction I noticed it looked a lot like a flood map. Knowing that the flood interaction rule interacts with specified elements to disable them if they occur in the flood zone area. So I created a “tornado path” interaction rule as follows:

1.    I created a tornado path from the explosion element, deleting all the points not needed.
2.    I saved the new shape to my element library, naming it “tornado path.”
3.    I copied the flood interaction rule, renamed it “tornado path”, indicating the cause as “tornado path”, and checked the elements I wanted it to interact with – for this simple example just buildings.
4.    Because I don’t like the clutter that the red “X” causes for disabled buildings, I created a separate layer of disabled (=destroyed, in my example) by exporting the buildings as a CSV.
5.    I added a new field (attribute) named “Status”
6.    I saved the file a “all building” to keep for backup.
7.    I saved it again as “buildings OK” and deleted all records with “Active = False”. I added the value “No Damage” to the “Status” field. These are the buildings outside the tornado path.
8.    I saved “all buildings” again and deleted all records with “Active = True”. I added the value “Destroyed” to the “Status” field. These are the building inside the tornado path.
9.    Then I “turned off” the tornado path” interaction rule by un-checking the box indicating to use the rule “in this depiction”. This is so the interaction rule doesn’t run again when new building files are added.
10.     I deleted the buildings layer (i.e., all the original buildings) in my depiction and re-imported the two new buildings files, using two different symbols indicating their status. Additional levels of damage were indicated in the Status attribute by manually editing each element.
11.    Then using the new status value to filter certain buildings, the symbol outline color was specified to indicate “destroyed”, “major damage” or “minor damage”.

With the tornado path interaction disabled it is easy to see (without the red “X”) which buildings were spared and which were damaged, along with any additional hover text information desired.

Click here to download the depiction.

Screenshot of the depiction

Depiction of the Week - Tracking Tornado Damage

Depiction user and emergency manager Gordon McCraw interviewed

Depiction user and friend Gordon McCraw, emergency management director for Tillamook County, Oregon, was featured in an article and video interview with the Oregonian this week. The interview is below, and you can also learn a bit about how Gordon uses Depiction from this webinar recording from September, starring Gordon and two other emergency managers.

Congratulations to Gordon on the well-deserved attention! We’re proud to be helping him and many others like him make their communities safer.