Travel Time Reliability (TTR) is a measurement of the variation between a given time period versus "freeflow" condiitions, measured during overnight hours. The measurement: establishes a reliability value for AM, PM, and weekend peaks (and non-peak) by measuring the differences between these travel times versus the measures off-peak hours (from 11pm-5am).
Hourly travel speed averages are collected AM/PM weekday and Summer weekends using the following data timeframes:
- Weekdays: Mondays-Thursdays from 2nd Monday in September to 2nd Thursday in November
- Weekends: Second Friday in June to Second Sunday in August.
The CMS methodlooks at each of the "critical" movements at an intersection. This
method focuses on "raw" intersection capacity, that is, the ability for an intersection to process a given traffic demand (volume) with a given lane use configuration and given phase sequence. Measurement: Weekday traffic 6-9am for the AM period and 3-6pm in the PM period. LOS will be determined by the peak hour volumes for the AM and PM periods.
Using the comprehensive intersection crash ranking which includes:
- Crash Frequency
- Crash Severity (i.e. Fatal, injuries, property damage only crashes)
- Crashes by Type (i.e. front to rear, sideswipe, head on crashes)
Analysis includes a 3-year average of crashes at signalized and non-signalized intersections that average 10 or more crashes per year. Approximately 300 intersections meet the 10 crashes/yr. threshold.
NOTE: During the fall of 2018, the SR 141 corridor and the the US 13/SR 141 overpass were under construction, thus impacting travel speeds through these areas. Data on maps reflect those measured conditions during construction.
The map below contains the most recent congestion performance measures for the WILMAPCO region. These measures serve as the basis for identifying the top corridors for more in-depth analysis and for an input into the project prioritization process.