Please see the picture. The shoulder is around 4-foot in width and the rumble runs for about one and a half miles and is applied in accordance to the TDOT March 2010 spec. This rumble significantly adds to the safety of bicyclists by discouraging distracted motorists from drifting into bicyclists on the shoulder. It does no harm to bicycling with the wide shoulder. And it reduces road departure for motorists and is a win-win for all. Bicyclists also have an alternate route that parallels Wilson Pike.
The negative is the rumble is in a residential area on a road with posted speed limits less than 45 mph. One minor squeeze point is near in the southbound side near a guardrail. The TDOT Spec should call for no rumble within 4 feet of a guard rail.
North of Concord, Wilson Pike has no shoulder and steep drop-offs at the edge of the highway. No rumble was applied there and would do great harm if it was. For several miles south of Concord Wilson Pike retains this wide shoulder until the Brentwood City line. From here it enters scenic countryside and has little to no shoulder. No rumble was applied there and also would do great harm if it was,
PRIMARY CONSIDERATIONS OF NEW PROCEDURES FOR CYCLISTS
Bike Walk Tennessee (BWT) recognizes that bicyclists represent less than 1% of the users of Tennessee state roads and appreciates TDOT considerations to preserve the bicyclists ability to share these roads safely. For bicyclists no design of safety rumble strips eliminates their hazard for them. BWT recognize that rumble strips are proven to increase safety for motorists in some situations, but not in all cases. Considerable numbers of studies provide criteria where rumbling protects motorists and where it has little to no benefit, such as in urban settings. BWT request that TDOT utilize this run-off-the-road data and experience in evaluating candidates for future application.
The FHWA fully supports the following statement from the 1999 American Association of State Highway and Transportation Officials (AASHTO) Guide for the Development of Bicycle Facilities:
"Rumble strips or raised pavement markers are not recommended where shoulders are used by bicyclists unless there is a minimum clear path of 1 ft from the rumble strip to the traveled way, 4 feet from the rumble strip to the outside edge of paved shoulder, or 5 feet to adjacent guardrail, curb or other obstacle."
Rumble strips should only be installed when an adequate unobstructed width of paved surface remains available for bicycle use. To aid a bicyclist's movement to the left of a shoulder rumble strip when needed to avoid debris, make turns or avoid other shoulder users, some states provide periodic gaps of 10 ft to 12 ft between groups of the milled-in elements throughout the length of the shoulder rumble strip. A study by one state recommends a gap of 12 ft between milled-in elements of 28 feet to 48 feet. Other states have specified 10 ft gaps between 10 ft milled-in elements.
Small stones, sand and other debris often collect on roadway shoulders. Usually the air turbulence caused by passing traffic will keep the portion of the shoulder closest to traffic relatively clear of such debris. For this reason, most bicyclists prefer to ride on that portion of the shoulder nearest to traffic to avoid debris. To provide a clear area beyond the rumble strip for bicycle travel, highway maintenance agencies should periodically sweep shoulders along identified bicycle routes and other routes of high bicycle usage.
BIKE WALK TENNESSEE RECOMMENDS HIGHWAY AGENCIES ABIDE BY
1. Do not use indiscriminantly. Not all roads are reasonable candidates. Shoulder rumble strips be used on those roadways for which an engineering study or crash analysis suggests that the number of run-off-the-road crashes would likely be reduced by the presence of rumble strips.
2. Bicyclists should be made aware of the increased use of shoulder rumble strips and remain alert for their presence while riding along high-speed roadways.
3.Urban/Suburban area where prevailing speeds are less than 50mph: Rumble strips should not normally be used. Where rumble strips are being installed for the first time or where their use might be unexpected, appropriate signs and pavement markings alerting both motorists and cyclists to their presence are advisable.
4. All responsible agencies should work in cooperation with bicycle groups, enforcement agencies, emergency groups and other roadway users, to develop policies, design standards and implementation techniques that address the safety and operational needs of all roadway users.
BIKE WALK TENNESSEE RECOMMENDS HIGHWAY AGENCIES ABIDE BY
THESE SPECIFIC GUIDELINES
In those cases where highway agencies choose not to abide by FHWA guidelines as noted herein, we request the following considerations.
Review by TDOT Bike/Ped Coordinator verifying run-off-the-road statistics and low usage of the candidate route by bicyclists. Coordination with Bike Walk Tennessee to work with local bicyclists to determine the impact on them.
Shoulder Widths of 5 feet or greater: The rumble strip be placed on the fog line, thereby leaving bicyclists approximately 4 feet from the rumble strip to the outside edge of paved shoulder, or 5 feet to adjacent guardrail, curb or other obstacle."
Shoulder Widths of less than 3 feet approximate: Shoulder rumble strips or stripes should not be used unless overwhelming evidence of run-of-the-road accidents exist. Such shoulder widths allow for little to no recovery to the motorists and consequently do not increases safety for motorists and only increase potential of injury to bicyclists.
Bicyclists do not object to techniques proven to increase road safety for all users. We object to the seemingly indiscriminant use on roads where such use provides little-to-no reduction for run-off-the-road accidents for motorists, while significantly increasing chances to a bicyclist for being injured or killed. (see Adventure Cycling comments). These indiscriminate uses violate guidelines from both the Federal Highway Administration and American Association of STATE Highway and Transportation Officials.
THE FEDS ABANDON BICYCLISTS' INTERESTS
I participated in an FHWA webinar when the, now rescinded, guidance T5040.39was launched. It signaled a sea change at FHWA, eliminating guidance regarding where to rumble with much broader language proposing to rumble a much more diverse set of roadways. Cyclists were a complete afterthought, with no mention of DOT's Equality Statement and cyclists accommodation subject to existing cyclist use.
Several state bike ped coordinators shared the materials provided on the webinar with LAB, the Alliance for Cycling & Walking, and Adventure Cycling. Representatives of those groups met with senior DOT/FHWA staff and hammered out the new language. We owe LAB, the Alliance and Adventure Cycling a big thank you for stepping in when they did.
Bud laumer, LCI
I have compared it to T 5040.35 which T5040.39 Rev 1replaces and have found the major changes I list below as they relate to bicyclists and pedestrians. We need to remember T 5040.35 was considerate of bicycle use on the road and States mostly disregarded those aspects to the detriment of bicyclists. It is difficult to imagine how T5040.39 will be received any differently.
Nevertheless, the coalition reported by Bud protested its release. I see no issues in the revision that should cause such dismay. It specifically includes Section 9 “Accommodation of All Road Users.” The primary changes that I noticed in the revision were
1) Inclusion of Edge line Rumble Strips, such as in the March 2010 TDOT spec. in addition to Shoulder Rumble Strips
2) Elimination of the T 5040.35 recommendation not to rumble roads with speeds less than 50 MPH.
3) Inclusion to rumble Urban roads in addition to Rural roads.
Whereas TDOT contractors appear to be rumbling almost every State road, our contacts at TDOT have shared with us (Bike Walk Tennessee) resurfacing project lists, primarily in the Nashville MPO region, before the jobs are let. We have identified level of bicycle use with the hope of favorably influencing the work. I am not aware of that oversight in other regions across Tennessee. That interaction is necessary for other planning offices across the State, since the numerous TDOT offices operate relatively independent of each other.
Tom Evans, BWT
IMPORTANT NOTE FOR BICYCLISTS
TDOT will be reviewing all new road resurfacing projects for its sensitivity to bicycle routes. They have hired RPM Transporation Consultants to help in this effort. RPM has considerable experience in designing bicycle facilities in Tennessee and was recognized by LAB as a Bicycle Friendly Business.
Nevertheless bicyclist must be PRO-ACTIVE and take this opportunity to identify popular routes for TDOT (see Note in upper left about Bike/Ped Coordinator review).
Initially, BWT set up MapMyRide to allow bicyclists to identify PREFERRED routes.: The response was so low that BWT abondoned it. As an alternative, contact the BWT Director in your region and ask what procedures s/he are following to protect popular routes from loss from rumbling. Submit to this director your popular bicycle routes.
Oct 2012 application on Wilson Pike south of Concord in Brentwood, TN.