I-6 Traffic Response ProgramArterial Service Patrol

Mobility StrategyEvaluation

Tom Ryan, HDRCarlos Sun, MU

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Meramec River

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• Areas of Study

– Tier 1– Tier 2– Tier 3– Tier 4

Two-Year Full Roadway Closure Evaluation

Arterial Service Patrol

Assessment Factors

• Reduction in traffic delay

• Reduction in fuel and emission

• Reduction in secondary crashes

• Reduction in response staff (emergency and operations)

• Improved public support

Arterial Service Patrol Public Support

I-64 Traffic Response Program is

Definitely Probably

Valuable 788 9

I-64 Traffic Response Program overall Very Satisfied Satisfied Very Dissatisfied

Percentage of Very Satisfied or

SatisfiedEffectiveness 754 29 1 99.9%

I-64 Traffic Response Operators are

Very Satisfied Satisfied Very Dissatisfied

Knowledgeable 739 42 1 99.9%

Courtesy 775 19 1 99.9%

Professionalism 772 23 1 99.9%

Safety Procedures 770 27 1 99.9%

Arterial Service Patrol Traffic Delay and Emission

Model Traffic Data Incident/ImpactBaseline 2007 No Incident

Post-construction 1a 2007 No IncidentPost-construction 2a 2007 Incident 5 minutes lane blockage Post-construction 1b 2007 Incident 15 minutes lane blockagePost-construction 2b 2008 Incident 15 minutes lane blockagePost-construction 3a 2007 Incident 30 minutes lane blockagePost-construction 3b 2008 Incident 30 minutes lane blockage

Response Time Mail-in Survey Information

Percent Accumulative Percent

Assists in 2008

Estimated Lane Closure

< 5 minutes 253 32.3% 32.3% 2074 20

5 to 10 minutes 250 31.9% 64.2% 2050 25

10 to 20 minutes 177 22.6% 86.7% 1451 30

20 to 30 minutes 61 7.8% 94.5% 500 40

30 to 40 minutes 24 3.1% 97.6% 197 50

> 40minutes 19 2.4% 100.0% 156 > 50

Total 784     6428  

Arterial Service Patrol Secondary Crash

• 2004 St. Louis Study By MU

• 5% Secondary Crash Factor

• Spatial and Temporal Thresholds

• 2007 Crash Data – Draft Report

• National Safety Council - Average Comprehensive Cost

Arterial Service Patrol Response Staff Savings

Highway Assist Multi-Organizations Assist Driver Assist

Debris Removal 1921 Spill 34 Tire 1346

I-70 Express Lane 4 Abandoned Vehicle 2211 Dispense Fluid 992

Signal/Lighting 209 Crash 2327 Lost Motorist 954

Signing 359 Mechanical 2811

Pavement 92

CMS/DMS 132

Construction Zone 77

Special Lighting 1

Dead Animals 315

Flooding 51

Ice/Snow 103

Total 3264 Totals 4572 Totals 6103

Arterial Service Patrol Results

Response Time Mail-in Survey Information

PercentIncidents in 2008

Estimated Lane Closure

Potential Savings

< 5 minutes 253 32.3% 2074 20 $3,170,433

5 to 10 minutes 250 31.9% 2050 25 $3,167,219

10 to 20 minutes 177 22.6% 1451 30 $2,339,754

20 to 30 minutes 61 7.8% 500 40 $806,356

30 to 40 minutes 24 3.1% 197 50 $317,255

> 40minutes 19 2.4% 156 > 50 $251,160

Total 784   6428   $10,052,176

  St. Louis St. Louis County Potential Potential

Secondary Cost per Estimated

Type of Crash County 2007 % by Type Crashes Crashes by Type Crash Type Savings

Fatal 17 0.2% 6 0.3 $4,100,000 $1,161,667

Serious Injury 168 1.7% 56 2.8 208,500 $583,800

Minor Injury 2228 22.6% 743 37.1 53,200 $1,975,493

Property Damage 7593 75.5% 2531 126.6 9,990 $1,264,235

Total 10006 3335 $4,985,195

Arterial Service Patrol Results

Total Savings    

Traffic Delay and Congestion Savings $1,266,574

Secondary Crash Savings $2,991,117

Response Staff Savings $57,977

Total Savings $4,315,668

Benefit/Cost 5.9

Program Cost 2008

Equipment Cost $23,520

Annual Cost - Labor, gas, etc. $703,980

$727,500

Where Do We Go From Here?Current Research and

Challenges

Assessment of Safety: Crash Analysis

• Challenges with attributing safety benefits

• How do we know which crashes were secondary? – MUAR 16. Traffic Conditions? – wrt Primary Incidents?

Secondary wrt Primary: Zone of Influence

• 2004

Distribution of Crash Severity

fatal injury pdo

I-70 3.00 271.00 670.00

I-270 3.00 219.00 555.00

total 6.00 490.00 1225.00

% 0.35 28.47 71.18

crash cost (1999) 3390000 44100 3220

Traffic Incident Management/ITS

• Everyone has a role: police, fire, EMS, HAZMAT, towing, MA/traffic response, TMC, media, the public

• What is the baseline in an evaluation?– How do we establish that baseline?

• Benefits in: detection, verification, traffic control, clearance? – Do benefits come from non-independent

sources?

Data Issues

• Self-selected samples, reliability– MA survey letters vs. randomized sample

• Resolution compatible with detail required– ITS: real-time, dynamic, fine resolution

• I think the data is there, but alas!

Include Us (Evaluators) Early, Please

• ITS evaluations are intensely data driven

• Include the evaluators ahead of time– to get baseline data– to ascertain if data currently being

collected is adequate– to make recommendations on what data

to archive