PC Calculator Testing New Service

The ISRB PCC runs using webservices. The ISRB does not attempt to maintain a database of geocoded addressess for the State of Idaho. The current Geocoding service ESRI is discontinuing there service. The PCC has been recoded to access the webservice provided by Microsoft's Virtual Earth. Virtual Earth we are told uses a combination of NAVTEQ and Tele Atlas data.
We are testing the new service by running request we receive through both the production server and the test server. What we have found that is some parts of Idaho Virtual Earth codes to what appears to be the front door of a building. In other part it codes to the street.

In places where it codes to the street we get good matches between the two systems. However the coding to the building has presented some problems. Let me explain. The returned geocode or Lat/Long is projected on a dataset resembling a polygon called a shapefile. A shapefile has been created that goes from every fire hydrant that we have geocoded, down the center of each and every street for a distance of 1,000 feet. The Shapefile is then expanded from the center of the street 50 feet on both sides and the end of the street. This watersystem shapefile represents the rule in the Public Protection Classification Manual - Idaho for how the distance to a fire hydrant is determined. When a returned geocode is at the building. The building may be back off the street more that 50 feet. We miss hitting the water layer by that much.

The other problem we have with both systems is that the street data geocoding. Does not always matchup well with the shapefiles we receive from the State of Idaho for taxing districts. We notice this most when boundaries touch and run down the center of streets.

Since the ESRI service is closing the end of June 2009. We will be changing soon.