Data Set Description:
This layer delineates the centerlines in each direction of the major interstates only.
Non-standard Attributes in table:
- PREFIX = Prefix to freeway name (e.g. North).
- NAME = Freeway's Name or Number.
- TYPE = Freeway (fwy) or On ramp (on.r) or Off ramp (Off.)
- CFCC = Census feature class
- TRANS = Codes used for the establishment of impedances (e.g. 6 = freeway where traffic flow is opposite arc digitization direction, 7 = freeway where traffic flow matches arc digitization direction.)
- U_ID= Unique identification number
Data Source History:
The freeways were hand selected from the main "streets layer", along with on and off ramps. Only the major interstates were included in this layer; smaller road sized highways, such as Rtes. 185 and 61, were left out.
This layer was a sub-set of the street centerline layer, and is as accurate as the streets centerlines. Freeways with 3-dimensional features such as overpasses and tunnels were field-checked from a flashy convertible sportscar by Jonathan Lowe and Kyle Draganov to verify intersections and non-intersections with neighboring streets. The top was down.
No security restrictions.
No scheduled updates--changes to the damaged Cypress freeway are not captured.
The new Cypress Structure will be updated when accurate coordinates are available.