CMF / CRF Details

CMF ID: 11017

Install Texas U-Turn (Texas Turnaround)

Description: Texas U-turns allows vehicles traveling on a one-way frontage road to access the opposing direction one-way frontage road via a U-turn before the terminal intersections at the diamond interchange. This technique removes two potential left-turn maneuvers from the adjacent at-grade intersections.

Prior Condition: No Prior Condition(s)

Category: Intersection geometry

Study: Safety Evaluation for Turnarounds at Diamond Interchanges: Assessing the Texas U-Turn, Dixon et al., 2018

Star Quality Rating: 4 Stars   [View score details]
Rating Points Total: 115
Crash Modification Factor (CMF)
Value: 0.763
Adjusted Standard Error:
Unadjusted Standard Error: 0.0782
Crash Reduction Factor (CRF)
Value: 23.7   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 7.82
Crash Type: All
Crash Severity: All
Roadway Types: All
Street Type:
Minimum Number of Lanes: 2
Maximum Number of Lanes: 4
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather: Not specified
Road Division Type: Divided by Median
Minimum Speed Limit: 35
Maximum Speed Limit: 55
Speed Unit: mph
Speed Limit Comment:
Area Type: Not specified
Traffic Volume:
Average Traffic Volume:
Time of Day: All
If countermeasure is intersection-based
Intersection Type: Roadway/roadway (interchange ramp terminal)
Intersection Geometry:
Traffic Control: Signalized
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2009 to 2015
State: TX
Country: USA
Type of Methodology Used:
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Nov-09-2021
Comments: This CMF is for locations where the right-turn from the cross street originates from a shared lane and does not have a large turning radius or a raised island.