Crash Reduction Strategies for Work Zones...March 2009. Presentation Outline ... encountering...
Transcript of Crash Reduction Strategies for Work Zones...March 2009. Presentation Outline ... encountering...
Crash Reduction Strategies for Crash Reduction Strategies for ggWork ZonesWork Zones
Tracy Scriba, FHWA
Work Zone ConferenceMarch 2009
Presentation OutlinePresentation Outline
Work Zone Safety and Mobility Challengesy y gWork Zone Crash Reduction Strategies
ITSITSEffective TMPsP f M it iPerformance Monitoring
WZ Safety & Mobility ChallengesWZ Safety & Mobility ChallengesWZ Safety & Mobility ChallengesWZ Safety & Mobility Challenges
CongestionCongestionCongestionCongestionEndEnd--ofof--queue crashesqueue crashesDelayDelayDelayDelayDissatisfied motorists (private & commercial)Dissatisfied motorists (private & commercial)Diffi lt i hi l dDiffi lt i hi l dDifficulty in emergency vehicle access and responseDifficulty in emergency vehicle access and responseDelayed contractor vehicle access (reduced Delayed contractor vehicle access (reduced efficiency)efficiency)efficiency)efficiency)
Causes of CongestionCauses of CongestionCauses of CongestionCauses of Congestion
Source: “ Traffic Congestion and Reliability;” FHWA (September, 2005)
WZ Safety & Mobility ChallengesWZ Safety & Mobility Challenges
Speeding/Speed ManagementSpeeding/Speed ManagementSetting speed limitsSetting speed limitsSetting speed limitsSetting speed limitsCompliance with speed limitsCompliance with speed limitsLimited areas for law enforcement officer stationingLimited areas for law enforcement officer stationingLimited areas for law enforcement officer stationingLimited areas for law enforcement officer stationingLimited areas to pullover speedersLimited areas to pullover speeders
CrashesCrashesCrashesCrashesTimely incident detection and responseTimely incident detection and responseSecondary crashesSecondary crashesSecondary crashesSecondary crashesCongestionCongestionIntrusionsIntrusionsIntrusionsIntrusionsWork vehicle access/egressWork vehicle access/egress
WZ Crashes WZ Crashes –– A Few FactsA Few FactsR rR r nd Cr hnd Cr hRearRear--end Crashesend Crashes
RearRear--end crashes are overend crashes are over--representedrepresentedppCrashes with rearCrashes with rear--end impacts increased 7.1 to 83 % in work zones vs nonend impacts increased 7.1 to 83 % in work zones vs non--work zones (depending on study cited and location) work zones (depending on study cited and location)
2001 study of WZ crashes in Illinois:2001 study of WZ crashes in Illinois:2001 study of WZ crashes in Illinois:2001 study of WZ crashes in Illinois:More rearMore rear--end crashes during periods of work activity than during inactivityend crashes during periods of work activity than during inactivityMany rearMany rear--end crashes were severe end crashes were severe -- often the case when traffic traveling at often the case when traffic traveling at high speeds crashes into back of a vehicle moving slowly in a queuehigh speeds crashes into back of a vehicle moving slowly in a queuehigh speeds crashes into back of a vehicle moving slowly in a queuehigh speeds crashes into back of a vehicle moving slowly in a queue
Likely a result of creation of queues and congestion Likely a result of creation of queues and congestion during work activities:during work activities:gg
Closure of a traffic lane Closure of a traffic lane Construction equipment moving into and out of the work areaConstruction equipment moving into and out of the work area
Can reduce rearCan reduce rear--end crashes by avoiding the creation ofend crashes by avoiding the creation ofCan reduce rearCan reduce rear--end crashes by avoiding the creation of end crashes by avoiding the creation of traffic queuestraffic queues
WZ Crashes WZ Crashes –– A Few FactsA Few FactsDay work Day work –– Night workNight work
Th ri k f r h f r i di id l dri rTh ri k f r h f r i di id l dri rThe risk of a crash for an individual driver The risk of a crash for an individual driver encountering roadwork activity at night may go encountering roadwork activity at night may go up more percentageup more percentage--wise than during the daywise than during the dayup more percentageup more percentage wise than during the day. wise than during the day.
Ho e er lo er traffic demands at night can leadHo e er lo er traffic demands at night can leadHowever, lower traffic demands at night can lead However, lower traffic demands at night can lead to to fewer additional crashes in totalfewer additional crashes in total over the over the duration of a project than would otherwiseduration of a project than would otherwiseduration of a project than would otherwise duration of a project than would otherwise occur if the work were performed during the occur if the work were performed during the day.day.yy
WZ Safety & Mobility ChallengesWZ Safety & Mobility ChallengesWZ Safety & Mobility ChallengesWZ Safety & Mobility Challenges
Performance MonitoringPerformance MonitoringPerformance MonitoringPerformance MonitoringLack of dataLack of dataLimited personnel to gather dataLimited personnel to gather dataLimited personnel to gather dataLimited personnel to gather dataDifficulty in assessing impacts and estimating Difficulty in assessing impacts and estimating performanceperformanceperformanceperformanceUnknowns about appropriate work windowsUnknowns about appropriate work windowsUnknown effectiveness of WZ strategiesUnknown effectiveness of WZ strategiesUnknown effectiveness of WZ strategiesUnknown effectiveness of WZ strategies
Which work Which work zone will I get?zone will I get?
Context for WZ Crash ReductionContext for WZ Crash ReductionContext for WZ Crash ReductionContext for WZ Crash Reduction
Part of overall WZ managementPart of overall WZ managementgg
Effective work zone management requires:Effective work zone management requires:Effective work zone management requires:Effective work zone management requires:
Understanding the likely impacts of a WZUnderstanding the likely impacts of a WZSafety and Mobility ImpactsSafety and Mobility Impacts
A combination of strategiesA combination of strategiesStrategies should be chosen to solve specific Strategies should be chosen to solve specific problemsproblemspp
WZ Crash Reduction StrategiesWZ Crash Reduction StrategiesWZ Crash Reduction StrategiesWZ Crash Reduction Strategies
WZ crash reduction strategies include:WZ crash reduction strategies include:WZ crash reduction strategies include:WZ crash reduction strategies include:ITSITSEff i T i M Pl (TMP )Eff i T i M Pl (TMP )Effective Transportation Management Plans (TMPs)Effective Transportation Management Plans (TMPs)Monitoring WZ PerformanceMonitoring WZ Performance
Not allNot all--inclusive inclusive –– there are many othersthere are many others
How ITS Can HelpHow ITS Can HelpP t nti l B n fitP t nti l B n fitPotential BenefitsPotential Benefits
Improved mobility and traffic managementImproved mobility and traffic managementp y gp y gMore informed publicMore informed publicQuicker incident responseQuicker incident responseQuicker incident responseQuicker incident responseGreater safety of workers and travelersGreater safety of workers and travelersBetter PR and relationships with stakeholdersBetter PR and relationships with stakeholdersEnhanced speed managementEnhanced speed managementp gp gBetter understanding of traffic conditionsBetter understanding of traffic conditionsOne study showed a benefitOne study showed a benefit--cost ratio of 2:1cost ratio of 2:1One study showed a benefitOne study showed a benefit--cost ratio of 2:1, cost ratio of 2:1, another showed a Banother showed a B--C ratio of 6:1C ratio of 6:1
How ITS Can HelpHow ITS Can HelpApplicationsApplicationsApplicationsApplications
Traffic monitoring/managementTraffic monitoring/managementg gg gTraveler informationTraveler informationIncident managementIncident managementIncident managementIncident managementWorker safety/protectionWorker safety/protectionPerformance monitoringPerformance monitoringPerformance monitoringPerformance monitoringSetting allowable work hoursSetting allowable work hoursS d / fS d / fSpeed management/enforcementSpeed management/enforcementTracking and evaluation of Tracking and evaluation of
i i /di i ii i /di i icontract incentive/disincentivescontract incentive/disincentives
How ITS Can HelpHow ITS Can Helppp
CongestionCongestionEndEnd--ofof--queue crashesqueue crashesDelayDelayDissatisfied motorists (private & commercial)Dissatisfied motorists (private & commercial)Difficulty in emergency vehicle access and responseDifficulty in emergency vehicle access and responseDelayed contractor vehicle access (reduced Delayed contractor vehicle access (reduced efficiency)efficiency)
Speed detection and warning systemsSpeed detection and warning systemsTraveler information systems, active diversionTraveler information systems, active diversionT ave e o at o syste s, act ve d ve s oT ave e o at o syste s, act ve d ve s oData on best times to work and for deliveriesData on best times to work and for deliveries
Example Example -- Speed Detection and Speed Detection and Warning SystemsWarning Systems
Al t d i t l dAl t d i t l dAlerts drivers to slowed Alerts drivers to slowed or stopped traffic aheador stopped traffic aheadCan reduce rearCan reduce rear endendCan reduce rearCan reduce rear--end end crashes and secondary crashes and secondary crashescrashescrashescrashesUse sensors to detect Use sensors to detect queues/slow speeds and queues/slow speeds and q / pq / psignal the message board signal the message board to activateto activate
Example Example -- ConnDOT Interactive Project MapConnDOT Interactive Project Maphttp://www.dotdata.ct.gov/iti/master_iti.htmlhttp://www.dotdata.ct.gov/iti/master_iti.html
ConnDOT Work Zone InformationConnDOT Work Zone Information
• Road project info
• Incident info
• Near real-time streaming video
How ITS Can HelpHow ITS Can HelpHow ITS Can HelpHow ITS Can Help
Speeding/Speed ManagementSpeeding/Speed ManagementSpeeding/Speed ManagementSpeeding/Speed ManagementSetting speed limitsSetting speed limitsCompliance with speed limitsCompliance with speed limitsp pp pLimited areas for law enforcement Limited areas for law enforcement officer stationingofficer stationingLimited areas to pullover speedersLimited areas to pullover speeders
Speed monitoring systemsSpeed monitoring systemsVariable speed limit systemsVariable speed limit systemsp yp yAutomated enforcement systemsAutomated enforcement systems
Example Example -- VDOT VSL SystemVDOT VSL Systempp yyII--495/I495/I--95 Telegraph Road Interchange Redesign 95 Telegraph Road Interchange Redesign of Woodrow Wilson Bridge Projectof Woodrow Wilson Bridge Projectof Woodrow Wilson Bridge Project of Woodrow Wilson Bridge Project
Work expected 2008 to 2013Work expected 2008 to 2013Traffic reduced from 8 lanes to 6 longTraffic reduced from 8 lanes to 6 long--term (furtherterm (furtherTraffic reduced from 8 lanes to 6 longTraffic reduced from 8 lanes to 6 long term (further term (further shortshort--term lane closures at night)term lane closures at night)
SystemSystemyySpeed limits can vary from 55mph to 35 mphSpeed limits can vary from 55mph to 35 mphAs congestion builds, speed limit decreases to try to As congestion builds, speed limit decreases to try to g , p yg , p ymaintain smooth flow and avoid stopmaintain smooth flow and avoid stop--andand--go trafficgo trafficOperators monitor system Operators monitor system -- can override speed limits, can override speed limits, messagesmessagesActive enforcement used to increase complianceActive enforcement used to increase compliance
www.wilsonbridge.comwww.wilsonbridge.com
How ITS Can HelpHow ITS Can HelpppCrashesCrashes
Ti li f i id d i dTi li f i id d i dTimeliness of incident detection and responseTimeliness of incident detection and responseSecondary crashesSecondary crashesC tiC tiCongestionCongestionIntrusionsIntrusionsWork vehicle access/egressWork vehicle access/egressWork vehicle access/egressWork vehicle access/egress
Cameras and queue detection systemsCameras and queue detection systemsCameras and queue detection systemsCameras and queue detection systemsIntrusion alarmsIntrusion alarmsSi i f k i /l iSi i f k i /l iSigns warning of trucks entering/leaving Signs warning of trucks entering/leaving roadwayroadway
How ITS Can HelpHow ITS Can Help
A study of successful deployments A study of successful deployments showed that:showed that:showed that:showed that:5050--85% of drivers surveyed said they changed their 85% of drivers surveyed said they changed their route in response to WZ ITS info route in response to WZ ITS info (lower exposure)(lower exposure)sp s W Ssp s W S ( we e p e)( we e p e)Queue length reductions of 56Queue length reductions of 56--60% are possible60% are possibleSpeed monitoring displays reduced speeds by 4Speed monitoring displays reduced speeds by 4 66Speed monitoring displays reduced speeds by 4Speed monitoring displays reduced speeds by 4--6 6 mphmphOne study found a 20One study found a 20--40% reduction in vehicles40% reduction in vehiclesOne study found a 20One study found a 20 40% reduction in vehicles 40% reduction in vehicles traveling traveling >> 10 mph over the speed limit when 10 mph over the speed limit when SMDs are usedSMDs are used
FHWA ITS Effectiveness Study FHWA ITS Effectiveness Study ResultsResults 20082008Results Results -- 20082008
Reductions in aggressive maneuvers at WZ lane dropsReductions in aggressive maneuvers at WZ lane dropsMI: Forced merges were 7 times less frequent and dangerous mergesMI: Forced merges were 7 times less frequent and dangerous mergesMI: Forced merges were 7 times less frequent, and dangerous merges MI: Forced merges were 7 times less frequent, and dangerous merges were 3 times less frequent when the ITS system was on (flashers on)were 3 times less frequent when the ITS system was on (flashers on)
Significant traffic diversion during congestion, and Significant traffic diversion during congestion, and h d bilit t WZ t ffi d i id th d bilit t WZ t ffi d i id tenhanced ability to manage WZ traffic and incidentsenhanced ability to manage WZ traffic and incidentsTX: Average of 10 % diversion (range of 1 to 28 %)TX: Average of 10 % diversion (range of 1 to 28 %)DC: Average of 52 % (range of 3 to 90 %) lower mainline volumeDC: Average of 52 % (range of 3 to 90 %) lower mainline volume
Improved ability to react to stopped or slow trafficImproved ability to react to stopped or slow trafficAR: 82 % of surveyed drivers felt ITS system improved their ability to AR: 82 % of surveyed drivers felt ITS system improved their ability to react to stopped or slow trafficreact to stopped or slow trafficpppp
Driver perception of improved WZ safetyDriver perception of improved WZ safetyAR: 49 % of surveyed drivers said ITS messages made them feel safer, AR: 49 % of surveyed drivers said ITS messages made them feel safer, 17 % were neutral 32 % disagreed 2 % did not answer17 % were neutral 32 % disagreed 2 % did not answer17 % were neutral, 32 % disagreed, 2 % did not answer17 % were neutral, 32 % disagreed, 2 % did not answer
How TMPs Can HelpHow TMPs Can Helpow s Ca e pow s Ca e p
Set of coordinated strategiesSet of coordinated strategiesSet of coordinated strategies Set of coordinated strategies implemented to manage the implemented to manage the work zone impacts of awork zone impacts of awork zone impacts of a work zone impacts of a projectprojectRequired for all Federal AidRequired for all Federal AidRequired for all Federal Aid Required for all Federal Aid highway projects by the highway projects by the Work Zone Safety andWork Zone Safety andWork Zone Safety and Work Zone Safety and Mobility RuleMobility Rule
How TMPs Can HelpHow TMPs Can Helppp
Work zone management is increasingly complexWork zone management is increasingly complexI i ffi l i h d h iI i ffi l i h d h iIncreasing traffic volumes using the same roads that agencies Increasing traffic volumes using the same roads that agencies need to maintain and rehabilitateneed to maintain and rehabilitateNeed traffic management efforts beyond temporary traffic Need traffic management efforts beyond temporary traffic g y p yg y p ycontrol planscontrol plans
Has affects on: Has affects on: SafetySafetyMobilityMobilityConstructabilityConstructability
TMPs = more comprehensive approach to TMPs = more comprehensive approach to i WZ i ti WZ i tmanaging WZ impactsmanaging WZ impacts
TMP ComponentsTMP ComponentsTMP ComponentsTMP Components
Must always include a TemporaryMust always include a TemporaryMust always include a Temporary Must always include a Temporary Traffic Control Plan (TTC)Traffic Control Plan (TTC)ForFor significant projectssignificant projects, TMPs must, TMPs mustFor For significant projectssignificant projects, TMPs must , TMPs must also contain:also contain:
Traffic operations (TO) componentTraffic operations (TO) component Simply stated, a p ( ) pp ( ) pPublic information and outreach (PI) Public information and outreach (PI) component component
significant project is a project that the agency expects will cause a relatively
A TMP may be a single document, A TMP may be a single document, or several documents/plans or several documents/plans
il d hil d h
cause a relatively high level of disruption.
compiled togethercompiled together
TMP Strategies to Manage WZ ImpactsTMP Strategies to Manage WZ Impacts
Temporary Traffic Control Public Information (PI) Transportation OperationsTemporary Traffic Control (TTC) Strategies
Public Information (PI) Strategies
Transportation Operations (TO) Strategies
--Traffic control/design Traffic control/design --Public awareness Public awareness --Demand management Demand management approachesapproaches--Traffic control devices Traffic control devices --Project coordination, Project coordination,
--Motorist informationMotorist information --Corridor/network Corridor/network management management --WZ safety managementWZ safety management
contracting, and innovative contracting, and innovative constructionconstruction
--Traffic/incident Traffic/incident management & enforcementmanagement & enforcement
Designers are encouraged to consider these strategies early on in the Designers are encouraged to consider these strategies early on in the process for all projects, even if they aren’t included in the TMPprocess for all projects, even if they aren’t included in the TMP
TMPs Need to Be…TMPs Need to Be…TMPs Need to Be…TMPs Need to Be…
WellWell--thought outthought outWellWell thought outthought outStarted early in project developmentStarted early in project developmentCoordinated with other projects nearbyCoordinated with other projects nearbyCoordinated with other projects nearbyCoordinated with other projects nearbyContain a combination of strategiesContain a combination of strategiesFi h d l l f WZ iFi h d l l f WZ iFit the expected level of WZ impactsFit the expected level of WZ impactsFundedFundedUpdated as needed after project awardUpdated as needed after project awardImplemented!Implemented!Monitored Monitored –– and adjusted as neededand adjusted as needed
Identification of TMP StrategiesIdentification of TMP StrategiesIdentification of TMP StrategiesIdentification of TMP Strategies
Should be based on:Should be based on:Should be based on:Should be based on:project constraints project constraints type of work zone type of work zone anticipated WZ impacts anticipated WZ impacts construction phasing/staging planconstruction phasing/staging plan
Some agencies use strict lane closure policies/strategies Some agencies use strict lane closure policies/strategies or permissible lane closure times that must be followed or permissible lane closure times that must be followed
Agencies may use analysis tools to predict delays, Agencies may use analysis tools to predict delays, queues, and impacts of detours and compare these for queues, and impacts of detours and compare these for various strategiesvarious strategiesvarious strategies various strategies
ExampleExample -- MI DOT TMP TemplateMI DOT TMP TemplateExample Example MI DOT TMP TemplateMI DOT TMP Template
Table of Contents:Table of Contents:Table of Contents:Table of Contents:Executive SummaryExecutive SummaryTemporary Traffic Control Plan (TTCP)Temporary Traffic Control Plan (TTCP)Temporary Traffic Control Plan (TTCP)Temporary Traffic Control Plan (TTCP)Transportation Operations Plan (TOP)Transportation Operations Plan (TOP)P bli I f i Pl (PIP)P bli I f i Pl (PIP)Public Information Plan (PIP)Public Information Plan (PIP)Delay Calculation DetailsDelay Calculation DetailsAlternative Traffic ControlAlternative Traffic ControlVicinity Map or Location DiagramVicinity Map or Location Diagram
MI DOT TMP Executive SummaryMI DOT TMP Executive Summaryyy
Basic description Basic description -- Location, work typeLocation, work typeS ifi P j DS ifi P j DSpecific Project Data:Specific Project Data:
Letting DateLetting DateAnticipated Project Duration Anticipated Project Duration (Construction Start Date and (Construction Start Date and p jp j ((Completion Date)Completion Date)Existing Lane Widths Existing Lane Widths Existing Paved Shoulder WidthsExisting Paved Shoulder WidthsExisting Paved Shoulder WidthsExisting Paved Shoulder WidthsExisting Aggregate Shoulder WidthsExisting Aggregate Shoulder WidthsThreshold CriteriaThreshold Criteria
Which criteria were exceeded ?Which criteria were exceeded ?Which criteria were exceeded ? Which criteria were exceeded ? How was delay calculated?How was delay calculated?What is the source of traffic volumes?What is the source of traffic volumes?
Facility Details (e g ADT lanes)Facility Details (e g ADT lanes)Facility Details (e.g., ADT, lanes)Facility Details (e.g., ADT, lanes)CrashCrash AnalysisAnalysis andand SafetySafety ReviewReview
How Monitoring WZ Performance How Monitoring WZ Performance C H lC H lCan HelpCan Help
Gather data and Gather data and use ituse it!!Understand how work zones are performingUnderstand how work zones are performingIdentify issues and correct themIdentify issues and correct themyyMake improvements to enhance performanceMake improvements to enhance performance
Current work zonesCurrent work zonesIdentify issues and address them now!Identify issues and address them now!
Sample of work zonesSample of work zonesppLooks for trendsLooks for trendsAssess effectiveness of strategiesAssess effectiveness of strategiesggAdjust design standards and WZ policiesAdjust design standards and WZ policies
Sources of Performance DataSources of Performance Data
Lane closure, queue data from project personnelLane closure, queue data from project personnelCrash reportsCrash reportsVolume/occupancy data, speed data from existing Volume/occupancy data, speed data from existing sensorssensorsInstalling temporary ITS during a projectInstalling temporary ITS during a projectTMC dataTMC dataSamplingSamplingSamplingSampling
Student interns doing travel time runs, observing queuesStudent interns doing travel time runs, observing queuesRotating trailers with sensors to gather speed dataRotating trailers with sensors to gather speed dataRotating trailers with sensors to gather speed dataRotating trailers with sensors to gather speed data
WZ Performance Measurement Examples
Current Work ZonesCurrent Work ZonesNew Mexico New Mexico –– incident response, incident response, p ,p ,maneuverability issuesmaneuverability issuesQueue detection and managementQueue detection and managementQueue detection and managementQueue detection and management
Sample of Work ZonesSample of Work ZonesOhio Ohio –– merge areas, ramp backmerge areas, ramp back--ups, shoulder ups, shoulder widthswidths
Example Example -- New MexicoNew Mexico
Deployed a WZ ITS system at Big I reconstructDeployed a WZ ITS system at Big I reconstructSystem included cameras to:System included cameras to:System included cameras to:System included cameras to:
Help identify and quickly clear incidentsHelp identify and quickly clear incidentsMonitor flow of traffic and driver behaviorMonitor flow of traffic and driver behavior
Incident response and clearance time reduced from 45 Incident response and clearance time reduced from 45 minutes to 25 minutesminutes to 25 minutes –– secondary crashes avoidedsecondary crashes avoidedminutes to 25 minutes minutes to 25 minutes secondary crashes avoidedsecondary crashes avoided
Saw areas where drivers had difficulty navigating the Saw areas where drivers had difficulty navigating the k M d fi i h ik M d fi i h iwork zone. Made configuration changes to improve work zone. Made configuration changes to improve
traffic flow (e.g., retraffic flow (e.g., re--aligned a temporary ramp) aligned a temporary ramp) -- likely likely crashes avoidedcrashes avoidedcrashes avoidedcrashes avoided
Example Example -- Queue Detection and Queue Detection and ManagementManagement
Monitor performanceMonitor performanceMonitor performanceMonitor performanceIdentify queues that weren’t expectedIdentify queues that weren’t expectedM l d h i TMPM l d h i TMPMay lead to some changes in TMP:May lead to some changes in TMP:
Providing more info to the public (reduce volumes, Providing more info to the public (reduce volumes, l i )l i )alert motorists)alert motorists)
Moving advance warning signs further upstreamMoving advance warning signs further upstreamAdding a CMS to alert driversAdding a CMS to alert driversAdjusting lane closure schedule/work hoursAdjusting lane closure schedule/work hoursChanging law enforcement deployment/positioningChanging law enforcement deployment/positioning
ExampleExample -- OhioOhio
3 Categories of WZ performance monitoring3 Categories of WZ performance monitoring
Example Example OhioOhio
3 Categories of WZ performance monitoring 3 Categories of WZ performance monitoring data in Ohio:data in Ohio:
Historic Data (primarily crash)Historic Data (primarily crash)Historic Data (primarily crash)Historic Data (primarily crash)Near RealNear Real--time (also crash)time (also crash)RealReal time (mobilit /speed)time (mobilit /speed)RealReal--time (mobility/speed)time (mobility/speed)
37
U d b ODOT t h it i d i ith WZ f tU d b ODOT t h it i d i ith WZ f tWZ Crash Data in Ohio WZ Crash Data in Ohio -- HistoricHistoric
Used by ODOT to assess how it is doing with WZ safetyUsed by ODOT to assess how it is doing with WZ safetyConstruction Cost Awarded by ODOT vs. WZ Total Crashes
$1,400 8500
7409
6808
8039
$800
$1,000
$1,200
Mill
ions
7000
7500
8000
ne C
rash
es
577258546389
6808
$200
$400
$600
$$ in
M5500
6000
6500
# W
ork
Zon
$02001 2002 2003 2004 2005 2006
Year
5000
Awarded Amount LPA projects WZ CrashesWithWith
38 Crash Rate = Accidents/Million Vehicle Miles
ODOT’s Historical WZ Crash AnalysisODOT’s Historical WZ Crash Analysis
WZ CrashWZ Crash Rate=2.02
NON WZ Crash Rate Rate =1.19
ODOT’s Historical WZ Crash AnalysisODOT’s Historical WZ Crash Analysisyy
D ill d d i dD ill d d i dDrilled deeper into dataDrilled deeper into data
Logged and analyzed hundreds of WZ crashesLogged and analyzed hundreds of WZ crashes --Logged and analyzed hundreds of WZ crashes Logged and analyzed hundreds of WZ crashes looked for “abnormally” high concentrations of looked for “abnormally” high concentrations of crashescrashescrashescrashes
Analysis showed need for new/revised Analysis showed need for new/revised specifications & processesspecifications & processes
ODOT’s Historical WZ Crash AnalysisODOT’s Historical WZ Crash AnalysisO O s sto ca W C ash a ys sO O s sto ca W C ash a ys s
Results Results ––
Geometrics Geometrics -- The “abnormally” high The “abnormally” high concentrations of crashes showed there wereconcentrations of crashes showed there wereconcentrations of crashes showed there were concentrations of crashes showed there were major geometric contributing factors to Ohio’s major geometric contributing factors to Ohio’s work zone crashes:work zone crashes:work zone crashes:work zone crashes:
(a) Inadequate ramp merges(a) Inadequate ramp merges( ) q p g( ) q p g
(b) Inadequate off(b) Inadequate off--ramp capacityramp capacity
(c) Insufficient paved shoulders(c) Insufficient paved shoulders(c) Insufficient paved shoulders(c) Insufficient paved shoulders
ODOT’s Historical WZ Crash AnalysisODOT’s Historical WZ Crash Analysis
Ramp Merges Ramp Merges –– Created new standards for WZ onCreated new standards for WZ on--ramp ramp M i d b d il d i lM i d b d il d i lmerges. Merges are now required to be detailed in plans. merges. Merges are now required to be detailed in plans.
(now explicitly looked at in MOTAA)(now explicitly looked at in MOTAA)
Paved shoulders Paved shoulders –– Created “desired/minimum” cross Created “desired/minimum” cross section that requires a 2’ paved shoulder (now used insection that requires a 2’ paved shoulder (now used insection that requires a 2 paved shoulder (now used in section that requires a 2 paved shoulder (now used in MOTAA and detailed design)MOTAA and detailed design)
OffOff--RampRamp--Capacity Capacity –– Now explicitly looked for in Now explicitly looked for in Maintenance of Traffic Alternative Analysis (MOTAA)Maintenance of Traffic Alternative Analysis (MOTAA)Maintenance of Traffic Alternative Analysis (MOTAA)Maintenance of Traffic Alternative Analysis (MOTAA)
ODOT’s Historical WZ Crash AnalysisODOT’s Historical WZ Crash AnalysisPlPl-- Plans Plans --
Plan to perform historical WZ crash analysisPlan to perform historical WZ crash analysisPlan to perform historical WZ crash analysis Plan to perform historical WZ crash analysis every 2 years seeking additional “lessons every 2 years seeking additional “lessons learned”learned”learnedlearned
P li i / d d / ifi i ill bP li i / d d / ifi i ill bPolicies/standards/specifications will be Policies/standards/specifications will be changed as necessary to keep problems from changed as necessary to keep problems from h i ih i ihappening againhappening again
F i f tiF i f tiFor more information on For more information on work zone management work zone management gg
strategiesstrategies
www.fhwa.dot.gov/workzoneswww.fhwa.dot.gov/workzones