% Miles by Congestion Level
Updated Using 2022 Data

This measure reports the percent of roadway miles categorized as heavily congested, mildly congested, or uncongested. Each congestion category is classified based on average travel speeds that meet the corresponding congestion thresholds.

Methodology

Methodology: % Miles by Congestion Level

The % of Miles by Congestion Level measure for all vehicles is determined by summing the miles of roadway in the congestion category and then dividing it by the total system miles.

A roadway segment is categorized as heavily congested, mildly congested or uncongested if it meets the corresponding congestion thresholds. The thresholds are respective of the facility type, posted speed limit, and the area type.

Calculation

`"% Miles Heavily Congested ="` `(∑"Segment length whose travel speeds meet heavily congested threshold")/(∑"Segment length") × 100` `"% Miles Mildly Congested ="` `(∑"Segment length whose travel speeds meet mildly congested threshold")/(∑"Segment length") × 100` `"% Miles Uncongested ="`
`(∑"Segment length whose travel speeds meet uncongested threshold")/(∑"Segment length") × 100`

Reporting Periods

  • Peak Hour
  • Peak Period
  • Daily
  • Yearly
Definitions

Definitions: % Miles by Congestion Level

  • Area Type
    • Urbanized Area: An area with a population of at least 50,000 people.
    • Non-Urbanized Area: An area with a population less than 50,000 people.
  • Context Classification: A classification assigned to a roadway that broadly identifies the various built environments in Florida, based on existing or future land use characteristics, development patterns, and the roadway connectivity of an area. For more information about context class, please reference methodology document.
  • Facility Type
    • Arterials: Signalized roadways that primarily serve through traffic with average signalized intersection spacing of two miles or less.
    • Highways: High speed roadways with signal spacing greater than two miles per signal.
    • Freeway: A multilane, divided highway with at least two lanes for exclusive use of traffic in each direction and full control of ingress and egress.
  • Highway System: An integrated network of roads and highways for motor and non-motor transport. Each highway system has roadways that are exclusive to their respective system.
    • National Highway System (NHS): Roads designated by Congress as nationally important for inter-regional travel, including roads designated as connectors to NHS intermodal facilities.
    • State Highway System (SHS): Roads under the jurisdiction of the State of Florida, and maintained by the Florida Department of Transportation or a regional transportation commission; includes roads with Interstate, US, and SR numbers.
    • Strategic Intermodal System (SIS): Transportation system created by the Florida Legislature in 2003 to include statewide and regionally significant facilities and services, containing all forms of transportation for moving both people and goods, including linkages that provide for smooth and efficient transfers between modes and major facilities.
  • Reporting Periods
    • Peak Hour: 5:00 p.m. to 6:00 p.m. on a weekday. This hour is chosen to allow consistent comparisons among transportation modes. It may not be the hour of greatest travel for any given roadway, mode or area. The majority of travel typically occurs during the PM peak hour resulting in more congestion in the PM peak than observed in the AM peak.
    • Peak Period: 4:00 p.m. to 6:00 p.m. on a weekday in which travel is greatest. These peak period hours are chosen based on the hours of greatest travel in different area types.
  • Segment: A portion of roadway defined by two boundary points.
Download Data

Date of last refresh: 10/19/2023

SOURCES

FDOT - Traffic Characteristics Inventory
FDOT - Roadway Characteristics Inventory Feature 147 (Strategic Intermodal System) and Feature 311 (Speed Limits)
HERE Technologies - Travel Time Data