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					        Geocoding

  This is a very big issue for
municipalities, 911 and business.
     An overview, once again.


N
         Even
                      City Center
                                     Odd




Addressing typically follows common patterns in U.S.
 Addressing can follow theoretical
            standards


Oak St.
            299     200   198   100

            298     201   199   101
  Addresses are matched according
    to the theoretical standards

Oak St.
                    299              200 198            100

                    298             201    199          101




          For example: 221 Oak St. can be placed
          approximately ¼ of the length of the block.
      In reality, most streets do not
     have theoretical address ranges.

Oak St.
                        234            200     117               100

                        235           201      119               101




 It depends on the age of the neighborhood, size of lots, etc.
   Most street files have theoretical
   ranges, but some municipalities
          use actual ranges.
Oak St.
                    234              200 117            100

                    235             201    119          101




          So the example 221 Oak St. is placed in its
          actual location, near the end of the block.
  Remember, street layers are
shapefiles or geodatabases and
 therefore have “geography” –
     they have coordinates.

Therefore, when you match an
 address, the address now has
          geography.
            How 911 works:
• A landline (not a cell phone) is attached to
  an address
• An address can be matched to an address
  ranged street file
• When the operator receives a call, the phone
  number accesses a database with and
  address that is then matched to a street file.
                  Call to 911


                                911 Operator
Citizen
                                connects to
                                database with
                                citizen’s phone
                                number




Phone number is tied to
address – 221 Oak St.
An example of a real street layer:
 There can be more than one
address in a given street layer
There are many addressing
 options for street layers.
The street layer for Denton
        County 911
   You must become familiar with
      the layer attribute table




There are 3 road name fields in the Denton County 911 layer.
Editing road line features for use
  in address ranged purposes.




If you do not create intersections while editing the street file,
you only have 4 features and 4 records in the above graphic.
You cannot assign address ranges to the above file.
When creating lines, you must put in
nodes at intersections of where lines
       break into segments.

				
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posted:2/14/2012
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