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Center Line Rumble Stripes. Powerpoint presentation for HDMT February 25, 2010. (Draft 2/17/10). Average Deaths per year Cross Center Line Fatalities = 55/yr (2001 – 2009) Recent Cross Center Line Crash. Minimal Crash Report:
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Center Line Rumble Stripes • Powerpoint presentation for HDMT February 25, 2010. (Draft 2/17/10)
Average Deaths per year Cross Center Line Fatalities = 55/yr (2001 – 2009)Recent Cross Center Line Crash • Minimal Crash Report: • Case Number: 2010009844 Type: Fatality County: 58 Crash Date: 02062010 Time: 0137 Location: HWY 70 3/4 MILE NORTH OF COLUMBUS JUNCTION • Vehicle 1 Year: 1995 Make: HONDA Type: CIVIC Towed By: BELLS COLUMBUS JCT Driver Name: FRANCISCO CHARIZ-ORTIZ Age: 25 City & State of Residence: COLUMBUS JUNCTION,IA • Vehicle 2 Year: 1993 Make: TOYOTA Type: CAMRY Towed By: HYNKS OF MUSCATINE Driver Name: EZRA JAMES BARNETT Age: 29 City & State of Residence: COLUMBUS JUNCTION,IA • Injury 1 Type: Injured Name: NICHOLE LYNN VANDEL Age: 21 City & State of Residence: CONESVILLES,IA Seatbelt Use: Life saved by Seatbelt: Transported To: U OF IA Transported By: AIRCARE • Injury 2 Type: Fatality Name: LUKE MATTHEW HECK Age: 20 City & State of Residence: COLUMBUS JUNCTION,IA Seatbelt Use: Life saved by Seatbelt: Transported To: STACY-LEWIS FUNERAL Transported By: LOUISA CO AMBULANCE • Injury 3 Type: Fatality Name: SHARON KAY VANDEL Age: 42 City & State of Residence: CONESVILLE,IA Seatbelt Use: Life saved by Seatbelt: Transported To: STACY-LEWIS FUNERAL Transported By: STACY-LEWIS FUNERAL • Injury 4 Type: Fatality Name: EZRA JAMES BARNETT Age: 29 City & State of Residence: COLUMBUS JUNCTION,IA Seatbelt Use: Life saved by Seatbelt: Transported To: STACY-LEWIS FUNERAL Transported By: STACY-LEWIS FUNERAL • Injury 5 Type: Fatality Name: FRANCISCO CHARIZ-ORTIZ Age: 25 City & State of Residence: COLUMBUS JUNCTION, IA Seatbelt Use: Life saved by Seatbelt: Transported To: STACY-LEWIS FUNERAL Transported By: STACY-LEWIS FUNERAL • UNIT 2 WAS NORTHBOUND ON HWY 70UNIT 1 CROSSED CENTERLINE AND COLLIDED WITH UNIT 2 HEAD ONSTILL CURRENTLY UNDER INVESTIGATION ASSISTED BY LOUISA CO SO,COLUMBUS JUNCTION PD, COLUMBUS JUNCTION FIRE & RESCUE AND LOUISACOUNTY AMBULANCE Officer Name: ISP161 ANDREASEN Post: 13 Assisted By: ISP338 AND ISP491
Summary of State Guidance on Use of Centerline Rumble Strips • Many U.S. transportation agencies implement CLRS, and state guidelines often vary due to differing climates, road designs, and/or maintenance practices. To determine the CLRS design and placement guidelines used by different states, a survey was distributed via the National Safety Engineers Listserv to states adjacent to Iowa. Several representatives from state transportation agencies responded, and additional information was obtained from a review of state transportation agency websites. The information gathered about agency design and placement is summarized in the following. Installation guidelines for CLRS typically include safety considerations (such as crash risk) defined by individual jurisdictions. However, the thresholds for tolerable risks are not consistent across jurisdictions. When appropriate guidance is provided specifically for centerline rumble strips. In some cases, guidance applies to both centerline and shoulder rumble strips and is just referred to as rumble strip guidance. • Minnesota installs CLRS butcurrently has no state guidance for the installation of CLRS. The University of Minnesota is currently working on establishing guidelines. • Wisconsin installs CLRS. The University of Wisconsin-Madison is currently developing standardized guidance on the placement and design of shoulder rumble strip and CLRS installations. • Illinois considers the use of CLRS on two-lane highways experimental and has limited the devices’ use to locations with curves. Currently, CLRS are recommended to extend through the super-elevation transition of the curve. The rumble strips are similar to the design used by the Missouri Department of Transportation (MoDOT): 16 inches long by 7 inches wide, with a 5 inch gap spacing between strips and every third rumble strip omitted so that a different pattern results than that used for shoulder rumble strips. • Missouri specifies that “all two-lane major roads with new pavement will have centerline rumble strips unless the posted speed limit is less than 50 mph.” Additionally, CLRS are installed on major two-lane and minor roadways with a cross-centerline crash history. CLRS are not recommended on roadways with a travel way width of 20 feet or less. CLRS should only be applied on the mandated roadway segments when the pavement thickness is at least 1.75 inches, and rumble strips cannot be placed on any joints. In terms of design, CLRS are 12 inches wide and installed in a gapped pattern, except in passing lanes, where two sets of rumble strips are recommended. See Figures A1 and A2 in this chapter’s appendix. http://epg.modot.mo.gov/index.php?title=Category:626_Rumble_Strips
Summary of State Guidance on Use of Centerline Rumble Strips • Nebraska isestablishing a plan with the Nebraska Department of Roads (NDOR) to install milled-in CLRS on two-lane roads where a history of cross-centerline crashes has been identified. Tests performed by NDOR have confirmed the devices’ effectiveness, and standard drawings were created that specify a standard length of 12 inches in either a square pattern or “football” shaped pattern. See Figure A3 in this chapter’s appendix. http://www.nebraskatransportation.org/roadway-design/pdfs/stan-spec/information.pdf • South Dakota installs CLRS on roadway segments with a history of cross-centerline crashes. As of 2009, only one location in South Dakota, a one mile long section of US 14A with curves, has CLRS. • Kansas provides general inspection guidance. Kansas’ 2007 state policy also allows the use of milled-in continuous CLRS on all reconstruction, new construction, and overlay projects that are five miles or more in length. The policy indicates that “centerline rumble strips may be used on two-lane, Class Band C, rural highways with asphalt pavement surfaces 1.5 inches or more in depth and having a paced shoulder width of at least 3 ft.” To provide continuity between different roadway segments, CLRS may also be used at highway locations where the shoulder width changes. An engineering study is recommended for segments that do not meet these criteria (Rumble Strip Policy, 071307). • Florida indicates that use of audible and vibratory pavement markings on roadway centerlines for two-lane rural roads should be used only in cases where there is a history of cross-centerline crashes. • Idaho has installed several hundred miles of centerline and edge line rumble strips. District Traffic Engineers are the ones who decide where to place rumble stripes based on crash data and field visits. They also use a safety corridor approach in making the assessment. They have contracted with the University of Idaho to evaluate the effectiveness of their rumble strips. The earliest rumble strip installation occurred approximately five years ago. They expect the study to be completed by soon and plan to refine their procedure for selecting locations for installation of rumble strips based on report findings. • Colorado does not have guidelines for placement of rumble stripes. They install rumble strips in locations where crash data supports their use. They have standards on how rumble strips should be placed. • Michigan estimates that they have 1,450 miles of centerline rumble strips. They install centerline rumble strips on rural 2 or 4-lane undivided roads with a speed limit of 55 mph or higher.
Just as CLRS can differ by design, these devices can also differ by pattern. Continuous or alternating CLRS are the two most common patterns (Figures B and C, respectively) evaluated by researchers. For either of these patterns, rumble strips may be milled in adjacent to or on top of the centerline pavement markings and are typically 4 to 18 inches in length, 7 inches wide, and 12 inches apart from center to center. Alternatively, some state agencies install continuous rumble strips with the same design in an alternating pattern (e.g., Figure A) to differentiate the vibration and auditory signal of CLRS from that of shoulder rumbles strips/stripes. Another alternating pattern is used in Michigan, where every third milled-in rumble stripe is skipped (as shown in Figure C). FIG A: Continuous Alternating CLRS in Wisconsin on STH 142 FIG B: Continuous CLRS FIG C: Alternating CLRS in Michigan
FIG H: Continuous milled in CLRS and 12 inch milled in edge rumble strips on a curved segment of US-52 Dubuque County, Iowa
FIG : Continuous milled in CLRS and 12 inch milled in edge rumble strips on US-34 East of Creston, Iowa
FIG F: 5% MVCCC* * Will be updated summer of 2010 for 2001-2009
Possible Installation Policy Guidance It is recommended that the Iowa DOT establish statewide CLRS program that incorporates the following strategies: Install CLRS on all state two-lane primary roads with greater than 3,000 ADT and 2 foot or wider shoulders and at least 11 foot lane width. Install CLRS on all identified 5% cross centerline corridors as they are resurfaced (2 foot or wider shoulders and at least 11 foot lane width). Retrofit CLRS on all identified 5% cross centerline corridors if resurfacing was completed in the last 5 years. Proposed Design Guidance The Iowa DOT currently does not have standard designs for the installation of CLRS. It is recommended that Iowa DOT Office of Design (Methods Section) develop standards based upon HDMT directive. Consideration should be given to alternating pattern (skipping every third milling ) and narrowing the width of the painted centerlines to match the rumble stripe.
Fig : Possible design detail for Iowa Center Line Rumble Stripe