Appendix A. Information collected from State DOT Contacts and Websites
The following table contains the information provided by each DOT contact. Note that the information that was compatible with the database was incorporated into the database. The table below contains this same information, plus all other information that could not be included in the database.
Idaho Transportation Department (ITD)
A Traffic Manual published by ITD is available at http://www.itd.idaho.gov/manuals/Online_Manuals/Traffic/Traffic.htm.
Also, the TMC located in Boise is operated by ACHD. ACHD is responsible for controlling traffic signal systems and arterial street cameras and (according to the website) has been working with ITD to make this a joint center that controls operations on all arterial streets within Ada County and the Treasure Valley Freeway System.
Traffic and Safety Manual, Chapter 2, Permanent Changeable Message Signs Guidelines are available at http://www.iowadot.gov/traffic/manuals/pdf/02f.02.pdf. The excerpt below summarizes use of DMSs for road weather.
“CMSs may be used to display adverse weather, environmental, or roadway conditions downstream that may impact driver visibility and safety (e.g., fog, major snow storms, sand storms, icy roadway, high cross winds, broken pavement, etc.), or advise motorists of specific regulations due to the weather or roadway conditions. Messages, when used, are restricted to a specific location and a specific CMS. The roadway condition must be in the vicinity of the sign in use. General weather, environmental, or roadway condition information (ICY ROAD CONDITIONS AHEAD) is not permitted.
By special arrangement with the National Weather Service it is permissible to display winter weather warnings when they are issued. The Lead Forecaster for the area involved is to make the determination and request that the appropriate sign(s) be activated in accordance with the National Weather Service in Des Moines internal Policy LPI 96-02.”
Also, the policy below was developed for the use of DMSs for weather events.
Draft Updated 10-9-08
Non-Winter types of Messages: During this pilot project of deploying weather messages, only winter related messages will be posted on DMS across Iowa. In the future he DOT will consider other weather related messages, such as Tornado, Flash Floods, High Winds, Fog, etc.
Priority: Weather messages are 4th on the list of priorities. Here is the entire list.
For Winter Storm Warnings: In the past, the NWS (National Weather Service) has called the 24hr pager (877-999-4731) for District 1 staff in Des Moines and notified the DOT of a Winter Storm Warning. Beginning on November 1, 2008 the NWS will be directed to call the SEOPs 24/7/365 phone number of (515)-233-7900.
On some rare occasions, the NWS has been busy, and not called the DOT before a storm. SEOP Staff should monitor the NWS’s web page at www.nws.noaa.gov during possible storms and will need to determine when and what messages should be deployed.
For winter snow removal operations: District staff shall post messages, or request the SEOPS Center, on overhead DMS and Rest Area DMS based on their operations and weather in their area.
The Iowa DOT and the NWS (National Weather Service) have an informal agreement for posting of warnings on DMS dated 2/1/96 back to when we had DMS in Des Moines only. A copy of the letters back and forth from the DOT are included in the Appendix of this section.
Winter storm warnings are usually issued by the NWS many hours before the storm will hit a region. DOT staff must consider many factors such as storm intensity, location of DMS, regions affected by the storm, etc. Messages should begin to be displayed on DMS for drivers that will enter the affected region and no other DMS will be seen by the driver. As a general rule of thumb, NWS warnings should be displayed 2 hours before the warning begins.
NWS Winter Weather Events:
National Weather Service Winter Weather Outlook, Watch, Warning and Advisories are:
Definitions from the NWS:
Overhead DMS Messages for each of the above issued events from the NWS:
Outlook:. No messages shall be displayed on the DMS.
Watch: No messages shall be displayed on the DMS.
Warning: If a warning has been used, then display:
After the warning has been used, and snow plows are out, continue to display the storm warning.
Advisory: No messages shall be displayed on the DMS
DMS Messages that can be used when DOT Snow plows are out and no NWS warnings:
Alternative: DMS Messages that can be used after a storm when it is not apparent that Snow Plows are on the roadway and ramps.
What signs should be used to display warnings?
The Iowa DOT staff person who is tasked with deploying winter weather messages has the responsibility and discretion to determine what DMS should get a message. The message could be displayed on all DMS (overhead and rest area) state-wide, however, consideration should be given to use only the DMS that have the possibility of drivers encountering the storm area.
What about “Click it or Ticket” messages and weather is bad?
f any PSA (Public Service Announcement) is being displayed on DMS and the weather is turning bad (snow in the winter, thunder storm/tornados in the summer) DOT staff should remove the message in their area and/or change the message that would be more appropriate. For example, the “Snow Removal Equipment in Use – Use Caution” message would be appropriate if snow is falling and plows are on the road.
In METRO areas, MoDOT has been considering posting messages for known dramatic weather events (such as a tornado) but has not done so yet. They generally do not post general weather information (e.g., rain) because they want to reserve DMSs for specific or hazardous conditions. They will post messages related to ponding on roadway, generally indicating to slow down or do not enter. They will also post messages related to plowing operations.
From SCOUT TMC, they do manage DMS on I-70 corridor which is used for weather events using a different set of messages.
As a rule, NDOT does not post weather-related messages to advise motorists except in some high wind prone areas, when chains are required for snow events, or for potential road closures because of poor visibility due to sand storms (generally right before the road is closed). They have an automated system for posting wind advisory information Washoe Valley between Carson and Reno (See Best Practices in Road Weather Management for description of system).
The following messages are in the sign library used by the operators in dispatch. The Variable Message Sign (VMS) Guideline is available at: http://www.oregon.gov/ODOT/HWY/TRAFFIC-ROADWAY/docs/pdf/Guidelines_for_VMS_on_State_Highway.pdf.
In general, WSDOT does not post weather-related messages on their VMSs, per the statewide VMS policy.
Weather related hazards shall only be displayed if there is a need to inform motorists of an unexpected condition. VMSs will not generally be used to display road conditions due to apparent weather (e.g. icy roads during freezing winter weather). An exception may be to alert motorists to hazardous weather-related roadway conditions IF identifying a specific location, and using a specific sign (e.g. using the SR-3 N. sign with the following message "Ice on Roadway, 3 miles ahead at Sherman Hill" or the SR-16 VMS for "Severe side winds at Narrows Bridge") and the information is received and verified from reliable sources.
Below are some, but not all, specific messages that may be used. The approach is to post messages for conditions that would be unexpected. For example, if motorists have been driving in fog for several miles they would not typically see a VMS message about fog, the message would have shown up on a sign ahead of entering the fog condition.
|State||Is there a Daily Weather Update?||Is a map shown on the weather page?||Is weather information for specific locations provided?||Are road weather conditions on Interstate highways provided on a dedicated map or table?||Are road weather conditions for state, local or other roads provided on a dedicated map or table?||Does weather information include links to other states or regions?||Are special conditions noted (e.g., hurricanes, snow, tornadoes)?|
|District of Columbia (Washington DC)|