The first two are SR 274, Old Railroad Bed Road north or Coldwater Creek, TN. The first shows the curves and hills. The second shows rumbles applied next to a guardrail. This goes on for over a mile.
The third image shows rumbles on US 31 North of Chapel Hill, TN. All these are fairly recent. I don't think they are the latest bike friendly version but they do start at and follow the white line. The older version had the rumbles in the middle of and wandering all over the shoulder. So some progress but should these be done at all? They certainly do not fit the AASHTO guidelines.
But to keep things in perspective, Check out the last image, taken yesterday near Athens, GA. This is the standard in our neighboring states. Last photo courtesy of Bob Schofield, http://www.crazyguyonabike.com/doc/page/?o=RrzKj&page_id=125735&v=KN
Bruce
These 16-inch wide Rumbles do not meet the 2010 TDOT specifications TM16 and significantly violate FHWA and AASHTO Technical Guidelines for use of shoulder rumble strips that predate TM16. I would think failure of the State to follow established engineering safety standards would create a legal liability in cases where injury or worse results to bicyclists.
ReplyDeleteObviously the hoped-for culture change at TDoT hasn't fully trickled down to the front lines where it counts yet. Any plans to make a legal challenge and demand remediation in conformance to these standards? Or at least notify the TDoT Commissioner what his employees have done and the urgent need to modify the rumble strip machinery?
ReplyDeleteDTI
David, the Rumble that you see here is the "stripe" design that TDOT was experimenting with two years ago. Also, TDOT contracted many of the projects in 2009 before TDOT's 2010 Spec was approved by FHWA, but still cut in 2010. We do not know when this rumble was applied. I have no reason to believe TDOT is not living up to its promises.
ReplyDeleteFrom the wear, I'd guess the rumbles on 274 were done a couple of years ago. I think I remember someone telling me about US 31 last Jan. Both would have been before the new practice was in place.
ReplyDeleteTo be perfectly honest, the rumbles are not as much a factor in making these roads unsuitable for a cycle route as other factors but they certainly don't help. I question their utility for anyone's safety. It's been a while since I researched the literature but 2 years ago the only studies showing benefit were on interstate type roads. I like Ben's analogy of putting seat belts on one's sofa.
Bruce
Tom & Bruce, Thanks for presenting the historical context of these rumble strips, and my apologies for shooting from the lip; after seeing Aussie Bob's photo of a GA rumble strip (posted by Bruce) I will be more appreciative of what is right about our own TDoT.
ReplyDeleteDTI