Commercial Vehicle Operations
 
Data Management
 
Maintenance and Construction
 
Parking Management
 
Public Safety
 
Public Transportation
 
Support
 
Sustainable Travel
 
Traffic Management
 
Traveler Information
 
Vehicle Safety
 
Weather
 

Lessons Learned: Variable Speed Limits (TM20)

12 unique lessons found.

The Distance Between Consecutive Variable Speed Advisory (VSA) Signs Installed on State Highways Should Not Be Greater Than One-Half Mile According to a Caltrans Field Study.
Date Posted: 10/22/2021 | Source Date:
Beware that work zone construction equipment operating at low speed can block and interfere with portable traffic detection systems used to control variable speed limit systems in active work zones.
Date Posted: 07/23/2018 | Source Date:
Variable speed limit system site selection should be rigorous and incorporate analysis of existing speed profiles and roadway ingress/egress characteristics to assure proper spacing of VSL systems and sensor inputs.
Date Posted: 09/15/2017 | Source Date:
Pavement friction sensors should target travel lanes instead of shoulder areas where wet pavement can persist causing VSL systems to reduce traffic speeds without need.
Date Posted: 04/07/2017 | Source Date:
Variable advisory speed limit (VASL) systems encourage drivers to slow down gradually as they approach rural work zones.
Date Posted: 04/29/2014 | Source Date:
Ensure proper placement of variable speed limit (VSL) signs in a work zone and operate the VSL system consistently on a long term basis.
Date Posted: 11/16/2011 | Source Date:
Ensure compatibility of data format of the field-weather monitoring sensors with the central software in the transportation management center.
Date Posted: 08/04/2010 | Source Date:
Deploy a variable speed limit system only after the software systems required to support it are mature and reliable.
Date Posted: 11/09/2009 | Source Date:
Enable and enforce managed lane facilities using various ITS tools.
Date Posted: 04/18/2007 | Source Date:
Minimize problems in creating contractual arrangements for testing a new ITS technology by creating negotiating benchmarks, designing a partnership arrangement, and developing a separate procurement process for different technological components.
Date Posted: 09/16/2005 | Source Date:
ITS Deployment Evaluation

INTELLIGENT TRANSPORTATION SYSTEMS JOINT PROGRAM OFFICE

1200 New Jersey Avenue, SE
Washington, DC 20590

its.dot.gov

Focus Areas

Benefit Data

Cost Data

Deployment Statistics

Decision Support

Success Strategies

ITS Taxonomy

Help

Contact

Topics

Commercial Vehicle Operations

Data Management

Maintenance and Construction

Parking Management

Public Safety

Public Transportation

Support

Sustainable Travel

Traffic Management

Traveler Information

Vehicle Safety

Weather

 

U.S. Department of Transportation Office of the Assistant Secretary for Research and Technology (OST-R)
 
 
Web Policies and Notices | Accessibility | Careers | FOIA | Privacy Policy | Information Quality | No FEAR Act Data | Ethics
Civil Rights | Office of Inspector General | OIG Hotline | BusinessUSA | USA.gov | White House