Clients using data from ADOT cannot create accurate corridor studies.
Intersection Magic allows users to create a corridor study. A corridor study allows the user to select the primary street and an ordered list of cross streets. A corridor study includes all collisions between the list of cross streets, and allows the user to specify the feet away from the endpoints, feet from the primary street and feet from any intersection.
While the Arizona crash report form does contain North, South, East and West check boxes for direction from intersection. Files provided by ADOT lacks this information. ADOT data contains an Offset field in the Incident.txt file. The value of this field can be positive or negative. A positive value will indicate if the collision is North or East of the intersection, and negative value will indicate if the collision is South or West of the intersection. Without a specific direction Intersection Magic cannot determine if a collision is between two intersections.
Clients using ADOT data should not attempt to use corridor studies. As the direction from intersection can not be determined unexpected results may be rendered. Clients should create the individual diagrams for each intersection. Then combine the Diagrams that have been created(Select File/Build custom diagram…/By combining diagrams).