Dale -
As a follow-up to last week’s email, Wyoming has recently completed a research project for their first implementation of VSL. It includes a survey of several other DOT. The study’s final report can be accessed at: http://www.dot.state.wy.us/webdav/site/wydot/shared/Planning/Research/WYDOT_ElkMtnVSL_FinalReport.pdf
From: Larsen, Adam (FHWA)
Sent: Monday, November 29, 2010 4:33 PM
To: [log in to unmask]
Cc: [log in to unmask]; Petersen, Don (FHWA); Bonds, James (FHWA)
Subject: Variable Speed Limits for Weather
Dale –
Wyoming has fully implemented one segment of Variable Speed Limits and is in the process of rolling out several more segments in the near future after a successful study of the test site. The speed limit is adjusted for the segments where the weather (or other) conditions warrant based on real time traffic speed data. More details at: http://www.dot.state.wy.us/wydot/cache/bypass/news_info/news_releases?entryId=8618 and http://sphotos.ak.fbcdn.net/hphotos-ak-snc4/hs776.snc4/67606_477243181340_288387851340_7343586_6975059_n.jpg
I have heard rumors that WSDOT has had discussions with WYDOT ITS about VSL (possibly for Snoqualmie Pass).
FYI, Under the 2009 MUTCD regulatory variable speed limit signs are to have a white legend. See attached interpretation from FHWA’s MUTCD Team.
Wyoming also has a chain law that can apply to road segments during adverse weather. This is an alternative used to keep roads open. More details are available at: http://www.dot.state.wy.us/wydot/travel/winter/chain_law
If I can provide further information, please let me know.
Adam Larsen
Safety Program Engineer
FHWA
307-771-2951
-----Original Message-----
From: FHWA Freight Planning [mailto:[log in to unmask]] On Behalf Of Dale A Tabat
Sent: Monday, November 29, 2010 12:28 PM
Subject: Inclement weather speed limit reductions
The Washington State DOT is interested in information on the following:
1) Are there any states that decrease the posted speed limit in the event of inclement weather (snow and ice in particular) and if so how is that accomplished? Is the speed limit decrease applied to specific road segments only or can it be incorporated across a state's entire highway system?
Looking
for related information for all traffic in general and freight trucks in particular.
2) Are there any urban areas that issue chain requirements for freight trucks during snow/ice conditions?
Thank you for any input.
Dale A Tabat
Truck Freight Program and Policy Manager Washington State Departemnt of Transportation [log in to unmask]
