Tennessee/Major roads/Main

Highway Numbering

Tennessee currently observes the following Standardized Name nomenclature for Numbered Routes:

Road Type	Standardized Name
Freeways	I-XXX
US Highways	US-XXX
State Highways	TN-XXX
County Highways	CR-XXX

State Highway Signage

State highways are divided into primary and secondary classifications and use a different type of signage for each:

• Tennessee Primary State Route signage
  
• Tennessee Secondary State Route signage
  

Map editors should not treat primary and secondary state highways different from each other when dealing with road types.

Highway Naming

See Road names/USA and Road types/USA for general guidelines for naming and classifying roads.

Regarding Local and Alternate Names:

In situations where a highway passes through a town, the road in those areas is typically named something other than the numbered route. In these situations the road should be named based on the following conditions: If the local street signs provide guidance with the local name, that should be used as the primary name in the Waze map. The numbered route should be added as an alternate name. If the local signs only indicate the route number, then that should be the primary name and and the local road name should be added as an alternate name.

Example: TN-13 in Waverly, TN has a Local Name of S Church St. (as indicated by signage). The Primary Street Name of the segments is S Church St., while TN-13 is listed as an Alternate Street Name.

Regarding Overlapping Highways:

When two or more numbered highways (or interstates) run concurrently (one stretch of road has multiple route numbers), the segment should be named after the primary of the routes. The primary route will usually have one or more of the following attributes:

• The route whose mile markers are used for the concurrent segment
• The route whose exit numbers are used for the concurrent segment
• When the concurrency ends, the route whose path does not get signed as a numbered exit.

In Tennessee, most US highways are also assigned a "hidden" state route number. These routes are often unsigned when they share a concurrency with a US highway. For example, TN-1 follows US-70 and several other US highways across most of the state from Memphis to Bristol, but is only signed in certain areas. These state highway designations, where they exist, should be listed in the alternate name for the US highway segment.

Regarding Scenic Routes:

Although Tennessee's roads tend to be quite scenic in and of themselves, many highways are specially designated as scenic routes and are signed with a green and white mockingbird logo. However, the "Scenic" or "Scn" designations should not be included in road names on numbered highways, unless specifically named as such in state GIS sources. Do not treat these like bannered routes when determining road names.

Lists of Highways in Tennessee

A spreadsheet of Tennessee Numbered Highways for tracking renaming to the TN-XXX standard.

Interstate and US Highways in Tennessee

State Highways in Tennessee

Functional Classification

A road's type is determined by a two step method:

1. Classification via TDOT Functional Classification maps
2. Possible classification upgrade via highway type

Step 1: Classification via TDOT Generated Functional Classification

The Tennessee Functional Class Map is updated by the the Tennessee Department of Transporation (TDOT). The TN Functional Class Maps come in one of two types as specified in the text at the bottom right corner of each map: Urban Functional Classification, or Rural Functional Classification.

Using the TDOT maps, the Corresponding Waze Road Type is determined via the following two tables:

Urban Functional Classification

TDOT Functional Class	Corresponding Waze Road Type
Urban Interstate	Freeway
Other Freeways and Expressways	Freeway  (if Controlled-access highway) or  Major Highway  otherwise (see note below)
Urban Principal Arterial	Major Highway
Urban Minor Arterial	Minor Highway
Urban Collector	Primary Street

Rural Functional Classification

TDOT Functional Class	Corresponding Waze Road Type
Rural Interstate	Freeway
Rural Principal Arterial	Freeway  (if Controlled-access highway) or  Major Highway  otherwise (see note below)
Rural Minor Arterial	Minor Highway
Rural Major Collector	Primary Street
Rural Minor Collector	Primary Street

Note: The editor should check to see if a road is a Controlled-access highway to determine if it qualifies as a  Freeway . Partially-limited-access roads, however, should NOT be set to Freeway.

If a road is not shown on the Functional Classification Maps, it is deemed as a Local Road with a Waze Road Type of  Street .

Inconsistent switching between road types along a road is not wanted. Consistency is key. Do not change a road type for routing sake or to make it appear on the map at a higher speed.

Sometimes strictly following these functional classification guidelines will generate inconsistent Waze road types at boundaries between urban and rural maps. It is best to use the aerial maps and GPS data to find a logical location where a road should make the change in road type. These types of changes are usually at intersections with other roads (primary street and above) and sometimes incorporate a change in lane count (2-lane road transitions to 4-lane road). Prudent editor discretion is needed at these locations.

Step 2: Classification upgrades via highway type

Sometimes, after determining road type in step 1, a road will need to be upgraded if it is an Interstate, Federal Highway, or State Highway. The list below provides the minimum that a particular highway should be classified (e.g. a Urban Collector would be at a minimum a primary street, but it would be upgraded to a major highway if it was a US Highway or a minor highway if it were a State Highway).

•  Freeway  - Interstates
•  Major Highway  - US Highways
•  Minor Highway  - State Highways, US Business Highways

Quick Reference Table

Refer to this chart to determine the road type of a given paved public road based on the TN functional class.

To use this chart, first determine the functional class of a road. Secondly, determine whether it is a signed, numbered highway in a particular highway system.

Where the column for the road's highway system and the row for the road's Tennessee functional class meet, you will find the proper road type for that particular road.

A number of examples are given below the chart.

		Highway Systems
		Interstate	US Hwy	US Hwy BUS, SPUR, LOOP	State Hwy	Locally-maintained
	examples	I-40, I-75, I-240, I-275	US-70, US-11E, US-31W	US-412 BUS, US-11E BUS	TN-1, TN-33, TN-840	Sam Cooper Blvd.
T N F u n c t i o n a l C l a s s	Rural Interstate	Fw	N/A	N/A	N/A	N/A
	Urban Interstate	Fw	N/A	N/A	N/A	N/A
	Other Freeways and Expressways (Controlled-access highway)	N/A	Fw	Fw	Fw	Fw
	Other Freeways and Expressways (Partially-limited-access road)	N/A	Major	Major	Major	Major
	Rural Principal Arterial (Controlled-access highway)	N/A	Fw	Fw	Fw	Fw
	Rural Principal Arterial (Non-controlled-access highway)	N/A	Major	Major	Major	Major
	Urban Principal Arterial	N/A	Major	Major	Major	Major
	Rural Minor Arterial	N/A	Major	Minor	Minor	Minor
	Urban Minor Arterial	N/A	Major	Minor	Minor	Minor
	Rural Major Collector	N/A	Major	Minor	Minor	PS
	Rural Minor Collector	N/A	Major	Minor	Minor	PS
	Urban Collector	N/A	Major	Minor	Minor	PS
	Local/not mapped	N/A	Major	Minor	Minor	Street

For example,

• A State Highway that is a controlled-access highway classified as a Principal Arterial is a  Freeway .
• A State Highway that is a partially-limited-access road classified as a Principal Arterial is a  Major Highway .
• A US Highway classified as a Minor Arterial is a  Major Highway .
• A US Highway Business Route route classified as a Minor Arterial is a  Minor Highway .
• A State Highway classified as a Freeway is a  Freeway .
• A State Highway classified as a Principal Arterial is a  Major Highway .
• A State Highway classified as a Collector is a  Minor Highway .
• A locally-maintained road classified as an Principal Arterial is a  Major Highway .
• A locally-maintained road classified as a Collector is a  Primary Street .

Road Locking

Tennessee currently observes the following Locking Levels for Functional Classifications:

Segment Type	Abbr.	Lock
Freeway	Fw	5
Ramp	Highest lock of connected segment
Major Highway	MH	4
Minor Highway	mH	3
Primary Street	PS	2
Street	N/A	Automatic (1)

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