Comparing and merging with OSM
As of July 2011, there are several people interested in creating tools to facilitate comparing and merging this data with OSM. If interested, please contact the talk-us mailing list. This page will contain information on developments related to the creation of such tools. See Comparing OSM with other datasets for some ideas.
A good source of information is the 2010 TIGER/Line Shapefiles Technical Documentation, in particular this PDF document.
The road data is available as one shapefile per county, and available via FTP:
It may be worth looking at the landmark file, which contains points with MTFCC's C3061 (Cul-de-sac, highway=turning_circle), C3062 (Traffic Circle, highway=mini_roundabout), C3066 (Gate, barrier=gate), and C3067 (Toll Booth, barrier=toll_booth).
|MTFCC||OSM tag||Feature class||Feature class description||Notes|
Primary roads are generally divided, limited-access highways within the interstate highway system or under state management, and are distinguished by the presence of interchanges. These highways are accessible by ramps and may include some toll highways.
|Not to be confused with highway=primary (differing definition of primary).|
Secondary roads are main arteries, usually in the U.S. Highway, State Highway or County Highway system. These roads have one or more lanes of traffic in each direction, may or may not be divided, and usually have at-grade intersections with many other roads and driveways. They often have both a local name and a route number.
|Some may be considered highway=trunk or highway=secondary, needs investigation.|
|S1400||highway=unclassified||Local Neighborhood Road, Rural Road, City Street||
Generally a paved non-arterial street, road, or byway that usually has a single lane of traffic in each direction. Roads in this feature class may be privately or publicly maintained. Scenic park roads would be included in this feature class, as would (depending on the region of the country) some unpaved roads.
|Some may be considered highway=tertiary|
|S1500||highway=track||Vehicular Trail (4WD)||
An unpaved dirt trail where a four-wheel drive vehicle is required. These vehicular trails are found almost exclusively in very rural areas. Minor, unpaved roads usable by ordinary cars and trucks belong in the S1400 category.
A road that allows controlled access from adjacent roads onto a limited access highway, often in the form of a cloverleaf interchange. These roads are unaddressable.
|Some may be highway=primary_link, highway=secondary_link, or highway=tertiary_link. Additional processing may be needed to determine this.|
|S1640||highway=service||Service Drive usually along a limited access highway||
A road, usually paralleling a limited access highway, that provides access to structures along the highway. These roads can be named and may intersect with other roads.
|If named, these perhaps should be highway=unclassified.|
A path that is used for walking, being either too narrow for or legally restricted from vehicular traffic.
|Some could be considered highway=path|
A pedestrian passageway from one level to another by a series of steps.
A service road that does not generally have associated addressed structures and is usually unnamed. It is located at the rear of buildings and properties and is used for deliveries.
|Definition too general to additionally apply service=alley.|
|S1740||highway=service||Private Road for service vehicles (logging, oil fields, ranches, etc.)||
A road within private property that is privately maintained for service, extractive, or other purposes. These roads are often unnamed.
|Perhaps additionally use service=driveway or access=private.|
|S1750||N/A||Internal U.S. Census Bureau use.||Internal U.S. Census Bureau use.||Ignore, or investigate actual use.|
|S1780||highway=service||Parking Lot Road|| The main travel route for vehicles through a paved
|This may not always be service=parking_aisle, needs investigation.|
|S1820||highway=cycleway||Bike Path or Trail||
A path that is used for manual or small, motorized bicycles, being either too narrow for or legally restricted from vehicular traffic.
A path that is used for horses, being either too narrow for or legally restricted from vehicular traffic.
|S2000||N/A||Road Median||The unpaved area or barrier between the carriageways of a divided road.|
Feature Names Relationship File
According to section 6.3 of the technical documentation, "Feature Names", a separate file contains additional names that refer to the same edge (way in OSM terms). This Feature Names Relationship File, provided as one dBASE DBF file per county, contains the names and the TLID of the edge the name applies to. This allows multiple names to be assigned to the same feature, such as "Richmond Highway" and "U.S. Hwy 1". Any person that plans to import parts of TIGER/Line data into OSM should consider this file to add alt_name=* and ref=* tags as appropriate.
In 2007 the TIGER attributes changed substantially, including a move to using MTFCC (MAF/TIGER Feature Class Code) classifier codes instead of CFCC (Census Feature Class Code). As a result, a new mapping should be established. A possible starting point can be found here on the TIGER 2009 page, though there are some errors in that document.
Appendix F of the 2010 Tiger/Line Shapefiles Technical Documentation lists all MTFCC definitions.
- CFCC: Census Feature Class Code (now deprecated in favor of MTFCC)
- FIPS: Federal Information Processing Standards
- MAF: U.S. Census Bureau Master Address File
- MTFCC: MAF/TIGER Feature Class Code (supersedes CFCC)
- TLID: TIGER/Line identifier (Permanent edge identifier)
- TIGER: U.S. Census Bureau Topologically Integrated Geographic Encoding and Referencing database
- TIGER/Line: extracts of selected geographic and cartographic information from the MAF/TIGER database
Better data than TIGER
Please note that some states and counties have higher quality and more recent data than TIGER, so please check the specific area before assuming TIGER has the best data. One such state is Virginia, which releases their road centerline data on a quarterly basis.