CCTV | DMS | HAR | RWIS | VSL | Dynamic Speed Displays | Ramp Meters| Curve Warning Systems| Intelligent Work Zones | ICWS

Planning Guidance for the Installation and Use of Technology Devices for Transportation Operations and Maintenance

ENTERPRISE Transportation Pooled Fund Study

DMS Guideline 1 - To Inform Travelers of Weather Conditions

Purpose: To provide road weather information to drivers so that the drivers can choose whether to continue travel on the route or whether to adjust their speed, route of travel, or divert from the trip in anticipation of an upcoming weather hazard.

The Manual on Uniform Traffic Control Devices (MUTCD) contains the national standards governing all traffic control devices. DMS (described as Changeable Message Signs in the MUTCD) are one traffic control device covered by the MUTCD (MUTCD 2009 Edition Chapter 2L. Changeable Message Signs. In MUTCD Section 2L:

Section 2L.01 addresses the description of Changeable Message Signs;

Section 2L.02 addresses applications of Changeable Message Signs;

Section 2L.03 addresses legibility and visibility of Changeable Message Signs;

Section 2L.04 addresses design characteristics of Changeable Message Signs;

Section 2L.05 addresses message length and information of Changeable Message Signs:

Section 2L.06 addresses installation of permanent Changeable Message Signs.

The planning guidelines are intended to be an additional tool to assist agencies in the decision process of selecting when and where to deploy DMS technologies, based up the experiences of agencies that have previously deployed DMS.

Engineering judgment should be used to asses potential implications that may result from installation of DMS. This planning guidance does not mandate the use of DMS.

The guidelines do not distinguish between types of DMS (portable, overhead, roadside).  Rather the intent of the guidelines are to contribute to the understanding of the need for some type of DMS.  Detailed design would contribute to the selection of the specific DMS type.

 

1. If the location is prone to weather situations that travelers would not otherwise be forewarned about (e.g. spots where fog regularly forms, bridges that ice early, mountain passes with weather that differs from approaches).

AND

2. If there is available road weather information for the area downstream of the candidate DMS location.

AND

3. If there is the capability (either manually by staff members or automated through a condition reporting system) to create event specific descriptions of weather conditions to be displayed on the DMS.

AND

4a. If there is a need to disseminate event specific descriptions (rather than a lower technology approach such as activating a flashing warning sign that says "Weather Alert When Flashing").

OR

4b. If there are options for either alternate routes or services, that might be described on the DMS, where travelers may wait out conditions.

OR

4c. If flashing beacon signs have been tried and not proven to generate responses from travelers.

AND

5. If weather events contribute to a significant number of crashes or road closures such that there are major impacts to travelers.

Guideline Advice:
If the only guideline being met for a DMS is the weather information guideline, then it is recommended that the lesser technologies are considered before deploying full DMS capabilities.

Partial Guideline Criteria:
If either #1 or #5 above are met, the guideline is considered ‘Partially Met’. If one or more additional purposes are partially met at this location for this device, the device should be considered.