There s a Killer on the Road What Can be Done about Roadway Departure Crashes? Rural Road Safety Webinar Series Thursday, November 3, 2011

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1 There s a Killer on the Road What Can be Done about Roadway Departure Crashes? Rural Road Safety Webinar Series Thursday, November 3, 2011 NACo is pleased to present this webinar in cooperation with the Federal Highway Administration and the National Association of County Engineers.

2 NACo Staff Contacts: James Davenport Program Manager Cindy Wasser Assistant

3 Tips for viewing this webinar: The box will collapse so that you can better view the presentation. To unhide the box, click the arrows on the top of the panel. The chat box is on the right side of the webinar window. If you are having technical difficulties, please send us a message via the chat box on your right. Our organizer will reply to you privately and help resolve the issue.

4 This webinar will be recorded and made available on line to NACo members to view later or review. Within the next few days you will receive an notice with the link to the recording with your webinar evaluation survey. Thank you in advance for completing the webinar evaluation survey. Your feedback is important to us.

5 Question and Answer Session Instructions Type your question into the chat window, and the moderator will read the question on your behalf.

6 Peer Exchange Program kicked off at: Developing County Solutions to Improve Rural Road Safety NACE 2009 Annual Meeting - Management & Technical Conference April 23 Peoria, IL Workshop Objectives: Develop a system for sharing rural road safety best practices among counties

There s a Killer on the Road What Can be Done about Roadway Departure Crashes? November 3, 2011 2:00 to 3:15 p.m. EDT Today s webinar focuses on Roadway Departures.

7 There s a Killer on the Road What Can be Done about Roadway Departure Crashes? November 3, :00 to 3:15 p.m. EDT Today s webinar focuses on Roadway Departures. A roadway departure crash is defined as a non-intersection crash which occurs after a vehicle crosses an edge line or a center line, or otherwise leaves the traveled roadway. Roadway Departure crashes typically account for 53% of highway fatalities each year. In addition, a high percentage of these fatal crashes occurred in rural areas. A recent review of FARS data showed that 74% of these Roadway Departure fatalities fell into 3 categories: 1. Overturns or rollovers 31% 2. Opposing direction crashes 24% 3. Crashes involving trees and shrubs 19% This webinar will provide comprehensive detail behind the seriousness of roadway departure crashes, why it is such a problem on rural and isolated roads, and the counter measures that counties can implement to reduce the number roadway departure crashes and the resultant fatalities.

8 Program 2:00 Welcome/House-keeping 2:05 Background Behind Roadway Departure Crashes Joe Cheung, FHWA Office of Safety 2:20 Curve Advisory Speed (Discuss key points of methodology) Robert J. Milstead, PE, PTOE Vice President Brudis & Associates, Inc. 2:35 Case Study Douglas County, GA (Describe Curve Action Plan and impact on crash reduction) Keary Lord, Assistant Director Douglas County DOT 2:50 Q&A 3:15 Conclusion

9 Joseph Cheung Roadway Departure Team in the FHWA Office of Safety Technologies

10 Robert J. Milstead, PE, PTOE Brudis & Associates, Inc. (410) ext 224 (410) Cell

11 Keary Lord - Assistant Director/Traffic Operations Division Manager Douglas County DOT Phone Fax klord@co.douglas.ga.us

12 Question and Answer Session Instructions Type your question into the chat window, and the moderator will read the question on your behalf.

13 Thank you for participating in NACo s webinar. For more information about NACo membership, contact Andrew Goldschmidt at agoldschmidt@naco.org or Ilene Manster at imanster@naco.org

14 Thank you for attending today s webinar. Please register to attend NACo s 2012 Legislative Conference and Exposition (March 3-7, 2012) at ges/default.aspx

15 Thank you for participating in NACo s webinar. To learn about future webinars, please visit on For more information on NACo s Rural Road Safety Resource Center please visit

16 THERE S A KILLER ON THE ROAD WHAT CAN BE DONE ABOUT ROADWAY DEPARTURE CRASHES? Roadway Departure Safety NACO November 2011 Joseph Cheung, P.E. Safety Technologies Office of Safety, FHWA

17 Roadway Departure Crash Definition: A non - intersection crash in which a vehicle crosses an edge line, a centerline, or otherwise leaves the traveled way. Roadway Departure Goals: 1. Keep the Vehicle on the Roadway 2. Reduce the Likelihood of a Crash 3. Minimize the Severity of Crashes that Occur

18 2009 National Fatal Crashes 16, 265 Roadway Departures (Source: FARS) Roadway Departure Strategies 1. Keep Vehicles on the Roadway Positive Guidance retroreflective signs and markings Safer Pavement - friction, rumbles, safety edge Focus on Curves 2. Reduce the Likelihood of Crashes Clear Zone - slopes, drainage features Remove, Redesign or Relocate Objects 3. Minimize the Severity of Crashes that Occur Breakaway Devices (Sign and Light Posts, Utility Poles) Shield Objects (Crashworthy Barriers, Bridge Rails, Terminals, Crash Cushions) 30,797 Total Crashes UNDESIGNATED ROADWAY DEPARTURES 2% 3

19 Horizontal Curve Fatal Crashes by Roadway Classification Note. Average crash rates for horizontal curves is about 3 times that of tangent segments

20 Roadway Departure Strategies 1. Keep Vehicles on the Roadway Positive Guidance retroreflective signs and markings Safer Pavement - friction, rumbles, safety edge Focus on Curves 2. Reduce the Likelihood of Crashes Clear Zone - slopes, drainage features Remove, Redesign or Relocate Objects 3. Minimize the Severity of Crashes that Occur Breakaway Devices (Sign and Light Posts, Utility Poles) Shield Objects (Crashworthy Barriers, Bridge Rails, Terminals, Crash Cushions)

Both typing and reading text messages by drivers

response events, a significant delay in response

lane position on the roadway sections, and a

21 Both typing and reading text messages by drivers will led to an increase in the number of missed response events, a significant delay in response time an increase in the standard deviation of lane position on the roadway sections, and a reduction in the number of glances to the forward roadway.

22 Did You Know? About one-third of all drivers arrested or convicted of driving while intoxicated or driving under the influence of alcohol are repeat offenders

24 First Priority: Keep the vehicle on the road! DELINEATION Delineation RUMBLE STRIPS

vibration to alert drivers that they are leaving the driving lane

25 Rumble Strips Raised or grooved patterns on the roadway that provide an audible warning (rumbling sound) and a physical vibration to alert drivers that they are leaving the driving lane Rumble Stripes Rumble strips that coincide with centerline or edgeline striping 10

26 Retroreflectivity Signs Guide Regulatory Warning Pavement markings Center line Edge line Roadway lighting Continuous lighting

27 Fatalities per Million Miles Travel ( ) Nighttime Source: National Safety Council Daytime

28 Signs Provide Critical Information to Drivers When Do We Replace Signs?

Standards for Nighttime Visibility - New sign standards effective Jan 22, 2008 - Requires methods to evaluate and maintain minimum levels -

29 Standards for Nighttime Visibility - New sign standards effective Jan 22, Requires methods to evaluate and maintain minimum levels - Retro values included in the Manual on Uniform Traffic Control Devices (MUTCD) - Phase-in period for compliance - Web:

30 Traditionally: longitudinal pavement markings: center lines, lane lines, edge lines Pavement markings are visual -- and ineffective in inclement weather, when worn, or when drivers don t look at them...

31 Why is Retroreflectivity Important? Visibility is critical for nighttime driving Daytime - many cues available Nighttime - few cues remain Driver s task more difficult

32 High-Friction Surface Treatments keep drivers on the roadway The Safety Edge provides drivers the opportunity to safely recover from a roadway departure Both are easy-to-apply, low-cost treatments that will result in saving lives and preventing many severe injuries

33 Targeted at severe roadway departure crashes. Crashes involving pavement edge drop-offs greater than 2.5 inches more severe and more likely to be fatal than other roadway departure crashes. 18

34 Paving technique where the interface between the roadway and graded shoulder is paved at an angle to eliminate vertical dropoff. 30 degree angled wedge. Created by fitting resurfacing equipment with a device that extrudes the shape of the pavement edge as the paver passes.

application other skidding (excessive speed) Reduce curve

35 Provide Skid Resistant Pavement Surfaces Crash Types addressed by improving pavement friction: wet weather application other skidding (excessive speed) Reduce curve crashes (28% of fatal crashes) Application by hand or by machine

36 1-21

Pavement Markings Chevron Signs One-direction Large

37 Add Shoulder Markings to Narrow lane Horizontal Curve Warning Sign Pavement Markings Penn DOT Zig-zag Pavement Markings Chevron Signs One-direction Large Arrow (W1-6)Sign Combination Horizontal Alignment/Advisory Sign

38 t Speed Feedback Sign Speed Activated Speed Limit Reminder Sign Transverse Rumble Strips Delineator Post Optical Speed Bar Speed Table Converging Chevron Marking Pattern

39 Second Priority: Remove all hazards!

41 Third Priority: Redesign the feature BREAKAWAY SIGN SUPPORT

42 Redesign the feature: Breakaway supports SLIP BASE BREAKAWAY SIGN SUPPORT

44 Fourth Priority: Shield the feature STEEL W-BEAM GUARDRAIL

Longitudinal barriers used to separate opposing traffic on a divided

42-inch tall concrete F-Shape or Constant Slope barriers.

Significantly reduce occurrence of cross-median crashes and the overall

45 Longitudinal barriers used to separate opposing traffic on a divided highway. They are medium to high cost countermeasures. W-beam guardrail. 42-inch tall concrete F-Shape or Constant Slope barriers. High-tension cable median barriers. Significantly reduce occurrence of cross-median crashes and the overall severity of median-related crashes. Use in medians up to 50 feet or wider. Barrier selection and placement are critical. 30

46 Highway Safety Manual

47 FHWA Division Offices FHWA Resource Center Safety & Design Team FHWA Office of Safety Research and Development FHWA Office of Safety, Headquarters Joseph Cheung FHWA Safety Program Web Site 32

48 Advisory Speed on Curves OR OR ADVISORY SPEED ON CURVES

49 Current Practices to Determine Advisory Speed ov/speedmgt/ref_mats/ fhwasa1122/ ADVISORY SPEED ON CURVES

50 Current Practices to Determine Advisory Speed Driver Comfort Speed Ball-Bank Indicator 85 th Percentile Speed Geometric Design Accelerometer Compass Method GPS Method ADVISORY SPEED ON CURVES

51 Current Practices>> Driver Comfort Speed Oldest method used for determining advisory speeds. Defined in the 1930s as that which causes an occupant of the vehicle to feel an outward pitch. Engineers later refined the definition to be that speed at which the driver s judgment recognized incipient instability. Drawbacks: most subjective and inconsistent results. ADVISORY SPEED ON CURVES

Current Practices>> Ball-Bank Indicator A curved level filled with a dampening liquid with a trapped air bubble or ball. Installed in a test vehicle: multiple test runs at 5-mph increments.

52 Current Practices>> Ball-Bank Indicator A curved level filled with a dampening liquid with a trapped air bubble or ball. Installed in a test vehicle: multiple test runs at 5-mph increments. Indicate the geometric degree of tip, tilt, or lean of a curve roadway. Advisory speed is the highest test speed that does not exceed threshold. Most widely used instrument for determining advisory speeds by 82% of agencies (Lyles and Taylor, 2006). ADVISORY SPEED ON CURVES

53 Varied Criteria Current Practices>> Ball-Bank Indicator May lead to different advisory speed recommendations. Speed Ball-Bank Threshold 2004 AASHTO 2003 MUTCD 2009 MUTCD 20 mph mph mph for Truck ADVISORY SPEED ON CURVES

54 Wide variation in reading along curve Expectation of constant reading along curve May differ by directions based on superelevation Ball-Bank Reading, degrees Current Practices>> Ball-Bank Indicator Curve 1 50 mph test speed Typical Expected Relationship Curve to Curve the Left to the Left Curve to the Right Curve to the Right Travel Time Along Curve, s Data Source: TTI Horizontal Curve Signing Workshop (Nov 2008) ADVISORY SPEED ON CURVES

55 Current Practices>> Ball-Bank Indicator Sources of Variability Use of different test vehicles Personnel training Instrument calibration quality Speed Steering corrections Tire slip Pavement variability Roughness Superelevation Friction supply ADVISORY SPEED ON CURVES Can control Difficult to control Cannot control

56 Current Practices>> 85 th Percentile Speed Measuring speeds at which all drivers drive along a curve in a free flow condition. Set advisory speed at the level which 85% of all drivers drive at, or below. Represents the largest number of drivers within a narrow pace of 10 MPH. On target to provide the greatest level of safety for the majority. ADVISORY SPEED ON CURVES

57 Current Practices>> 85 th Percentile Speed However, given direct measurements of curve speed distribution and vehicle classification, No consensus on how to determine appropriate advisory speeds 85 th %, average, or median speeds? Passenger cars, trucks or all? What do you think? MUTCD 2009 no longer provides explicit support to this method ADVISORY SPEED ON CURVES

Current Practices>> Geometric Design AASHTO calculates an advisory speed by: V² = 15 (e + f) R Where: V = Advisory Speed of vehicle in MPH e = Superelevation in foot per foot of

58 Current Practices>> Geometric Design AASHTO calculates an advisory speed by: V² = 15 (e + f) R Where: V = Advisory Speed of vehicle in MPH e = Superelevation in foot per foot of horizontal width f = Transverse coefficient of friction R = Radius of curvature in feet Source of variability: value of transverse coefficient of friction. ADVISORY SPEED ON CURVES

Current Practices>> Accelerometer Example:

59 Current Practices>> Accelerometer Example: Electronic Accelerometer A gravity-sensitive electronic device Measure the lateral forces and accelerations that drivers experience while traversing a highway curve. Alternative to the ball-bank indicator. (AASHTO s 2004 Green Book) ADVISORY SPEED ON CURVES

60 Advisory Speed Recommendation Under normal conditions, the suggested Advisory Speed for comfort in a passenger vehicle is when the average lateral gravitational force equals 0.28 g-ft/sec² A measurement of 0.26 g-ft/sec² to 0.30 g-ft/sec² is considered an acceptable range for establishing Advisory Speeds. ADVISORY SPEED ON CURVES

Electronic Ball-Bank Indicator Laptop Computer with TRAMS* * TRAMS:

61 Current Practices>> TTI Methods Compass Method Compass Ball-Bank Indicator Distance-Measuring Instrument GPS Method GPS Receiver Electronic Ball-Bank Indicator Laptop Computer with TRAMS* * TRAMS: Texas Roadway Analysis and Measurement Software ADVISORY SPEED ON CURVES

62 TTI Curve Speed Prediction Model Determination of Advisory Speed Advisory speed is a function of curve deflection angle; superelevation rate; curve length; 85 th % curve speed (observed or estimated). The procedure is automated by a spreadsheet program Curve Advisory Speed Worksheet Source: Horizontal Curve Signing Handbook (TTI, Oct 2008) Curve Geometry ADVISORY SPEED ON CURVES

63 Curve Advisory Speed Worksheet An Excel Spreadsheet based on and enhanced from Texas Curve Advisory Speed Software Calculates Advisory Speed for Compass Method GPS Method TTI Curve Speed Predication Model Provides Curve Signing Guidelines for TTI methods; or Other sources (Accelerometer, AASHTO geometric design equation, Ball-bank indicator, 85 th % speed ) ADVISORY SPEED ON CURVES

64 Curve Advisory Speed Worksheet Analysis General Info. Input Data Alternate Input Data Advisory Speed Traffic Control Device Guidance ADVISORY SPEED ON CURVES

65 Curve Advisory Speed Worksheet Analysis General Info. Input Data Alternate Input Data Advisory Speed Traffic Control Device Guidance ADVISORY SPEED ON CURVES

66 Curve Advisory Speed Worksheet Analysis General Info. Input Data Alternate Input Data Advisory Speed Traffic Control Device Guidance Warning signs (follow MUTCD 2009 guidelines) ADVISORY SPEED ON CURVES

67 Summary Importance of advisory speed and curve signing: SAFETY Advisory speed should be consistent with driver expectation. Devices should be uniform among curves of similar geometry, character, and road conditions. Current practices: lack of uniformity and inconsistent Proposed procedures and software are uncomplicated and easy to implement. ADVISORY SPEED ON CURVES

68 The End ref_mats/fhwasa1122/ Contact Robert J. Milstead, PE, PTOE Vice President Brudis & Associates, Inc Rumsey Road, Suite C Columbia, MD rmilstead@brudis.com Phone: (410) ext. 224 Fax: (410) ADVISORY SPEED ON CURVES

69 Douglas County Department of Transportation Moving Douglas County Forward Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar November 2011 Keary B. Lord Deputy Director, Operations Douglas County, Georgia Department of Transportation Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

70 Presentation Objectives Give background on County Brief discussion of conditions/challenges Describe efforts that led to development of County Safety Action Plan (SAP) Describe Curve Safety Program element of the SAP Mention other aspects of the SAP Describe results of SAP implementation Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

Douglas County Douglas County: is located 20 miles west of Atlanta on Interstate 20 Formation of the DOT Focus on traffic operations Biggest need is Traffic Engineering 101 is within ARC s core 10

71 Douglas County Douglas County: is located 20 miles west of Atlanta on Interstate 20 Formation of the DOT Focus on traffic operations Biggest need is Traffic Engineering 101 is within ARC s core 10 counties in the RDC planning area contains 200 square miles of gently rolling foothills of the Appalachian Piedmont is bordered on the south by the Chattahoochee River/Fulton County, northeast by Cobb County, north by Paulding County, and west by Carroll County. ATLANTA Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

72 Conditions / Challenges Farm to market infrastructure (note that road is built between the house and the barn) Pavement condition is excellent! Markings are excellent! Lane width is 12 feet Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

distance NO shoulders / fixed objects Insufficient clear zones Sharp

73 Present conditions/challenges Good pavement conditions, good markings Poor alignment, narrow right-of-way Intersections without sight distance NO shoulders / fixed objects Insufficient clear zones Sharp curves Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

74 Douglas County s Population.. is currently 132,400 (2010 data) has increased 43.6% since 2000 Douglas County Historic and Current Population has avg annual growth rate of 3% since 1980, 3.3% since 1990, and 4.7% since 2000 third fastest growing county in the 10-county region since 2000 at 1 persons per acre, is the eighth most dense county in 20-county region Population Year Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

Crash Analysis, Statistics & Information, GDOT CASI Report Georgia Licensed Drivers Valid and Suspended County 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 CHEROKEE 75249

75 Crash Analysis, Statistics & Information, GDOT CASI Report Georgia Licensed Drivers Valid and Suspended County CHEROKEE COBB DEKALB DOUGLAS FULTON PAULDING GEORGIA CASI Report Motor Vehicle Crashes Number and Rate per 10,000 Licensed Driver County CHEROKEE Number CHEROKEE Rate COBB Number COBB Rate DEKALB Number DEKALB Rate DOUGLAS Number DOUGLAS Rate FULTON Number FULTON Rate PAULDING Number PAULDING Rate GEORGIA Number GEORGIA Rate Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

Crash Analysis, Statistics & Information Douglas County included with counties with a crash rate higher than the State s crash rate included with counties with highest Growth

76 Crash Analysis, Statistics & Information Douglas County included with counties with a crash rate higher than the State s crash rate included with counties with highest Growth increase in Motor Vehicle Crashes included with counties with highest Rate for Crash Rates per 10,000 Licensed Drivers Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

77 CASI Conclusion With population growth comes an increase in drivers, vehicles, the miles they travel and of crashes. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

which have most potential for crash reduction Focus on low cost/high benefit solutions Train and educate staff to read the road,

78 Douglas County SAP Goals Make safety the highest priority Safety money should go where it achieves the greatest effect in terms of preventing crashes and reducing their severity Focus on locations with largest potential for safety improvement (PSI index) which have most potential for crash reduction Focus on low cost/high benefit solutions Train and educate staff to read the road, have an eye for safety, and promote safety attitude internally Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

79 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar Curve Safety Plan

80 Curve Safety Plan Prioritization (ranking) of 35 pilot locations Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

81 Curve Safety Plan Recommendations, construction documents/plan for each of the 35 curve locations Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

82 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

83 Improving Roadway Safety by minimizing impacts to vehicles that leave the roadway with vegetation and tree removal, improving shoulders of the roadway, and guardrail installations. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

84 Vegetation and Tree Removal along roadways to minimize impact to vehicles that may stray from the travel way. Studies have shown that removal of trees and vegetation immediately adjacent to the roadway significantly reduces the potential for an accident involving serious injury. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

A recovery zone can potentially provide areas that drivers can regain control of

85 Improving Shoulders along the roadways to provide a recovery area for vehicles that do leave the roadway. A recovery zone can potentially provide areas that drivers can regain control of their vehicles while off the roadway and get back on the roadway safely. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

86 Guardrail Installations in various locations to prevent vehicle rollovers at steep drop offs. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

and situations that might not readily be apparent to road users.

87 Enhancing Signage by doubling up on advanced warning signs and traffic control signs to call attention to unexpected conditions and situations that might not readily be apparent to road users. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

88 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

89 Installing Post-mounted Delineators and Chevrons to warn drivers of an approaching curve and provide tracking and guidance to the drivers. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

90 Installing Raised Pavement Markers to provide for increased delineation of the driving path and enhance the ability of the driver to track the roadway, particularly under nighttime, wet-weather, or adverse weather conditions. Providing Retroreflective Traffic Control Devices to illuminate the roadway and make the night time driving environment more visible to drivers. Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

91 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

92 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

93 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

94 Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

95 Douglas County Crashes # Crashes Year Before/after crash numbers showing reduction of crashes by 20% since Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

96 Moving Douglas County Forward Questions? Douglas County Safety Action Plan Keary B. Lord Deputy Director, Operations Douglas County, Georgia Department of Transportation Douglas County Safety Action Plan 2011 NACo Roadway Departure Webinar

What Engineering Can Do for You! Low Cost Countermeasures for Transportation Safety

What Engineering Can Do for You! Low Cost Countermeasures for Transportation Safety Adam Larsen Safety Engineer Federal Highway Administration 360-619-7751 Adam.Larsen@DOT.GOV Adam Larsen TTP Safety Engineer