Ohio DOT Crash Analysis Presentation

Slide 01

Work Zone Safety & Mobility

Excerpts from a presentation given at the Montana Regional Work Zone Rule Workshop in April 2006.

Dave Holstein

ODOT Office of Traffic Engineering

dave.holstein@dot.state.oh.us

614-644-8137

Slide 02

Linking Safety and Congestion

In Ohio

43% of all Interstate crashes happen on 12% of the Interstate system.
19% of all NON Interstate crashes happen on 2% of the NON Interstate system.
When overlaid against Ohio’s congested locations the 12% (IR) and 2% (NON IR) are an almost exact match to the congested locations.
Congestion causes crashes

Slide 03

Linking Safety and Congestion

Historical WZ crash analysis in Ohio shows that congested work zones CAUSE CRASHES.
Much of ODOT’s WZ processes revolve around identifying work zone capacity needs and determining constraints to providing that necessary capacity.

Slide 04

Why Maintenance of Traffic (MOT) is Important in Ohio

35th in geographical size
10th largest highway network
5th highest volume of traffic
5th highest volume of truck traffic
4th largest interstate network
2002 NCAA Football Champions

Slide 05

Why MOT is Important in Ohio

Need to comply with the new Federal Regulations on Work Zone Safety and Mobility (23 CFR 630 –Subpart J)
- October 2007 Deadline

Slide 06

Why MOT is Important in Ohio

Because We Can Make a Difference

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Slide 07

Why MOT is Important in Ohio

In addition to mobility, safety, and economic reasons for good work zone processes……………
Our Governor got REALLY mad when he was stopped in a work zone!!

Slide 08

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical WZ Crash Data

630.1008 State Level Processes and Procedures
- “Shall use field observations, wz crash data….”
- “Shall continually pursue improvement of wz safety and mobility by analyzing work zone crash and operational data from multiple projects….”

Slide 09

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

Why did we do the analysis?
- ODOT is embarking on the largest construction program(s) in our history
- Director was concerned about the impact our work zones will have on crashes
- Question - Are the ODOT work zones causing more accidents?
  - If so, can we do more to limit the increase?

Slide 10

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

THE KNEE JERK REACTION

“Well of course we have more crashes in work zones. Narrow lanes, barriers next to lanes, and on… and on…. and on….”
Historical crash data analysis showed there were things we could do better!!

Slide 11

ODOT’s WZ Process in Terms of the New Federal WZ Regulations
Historical Crash Analysis

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Slide 12

ODOT’s WZ Process in Terms of the New Federal WZ Regulations
Historical Crash Analysis

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Slide 13

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

Drilled deeper into data
Logged and analyzed hundreds of work zone crashes. Looked for “abnormally” high concentration of crashes.
Analysis showed need for new/revised specifications & processes

Slide 14

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

Results –
Geometrics - The “abnormally” high concentrations of crashes showed there were major geometric contributing factors to Ohio’s work zone crashes:

(a) Inadequate ramp merges
(b) Inadequate off-ramp capacity
(c) Insufficient paved shoulders

Slide 15

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

Ramp Merges – Created new standards for work zone on-ramp merges. Merges are now required to be detailed in plans. (now explicitly looked at in MOTAA)
Paved shoulders – Created “desired/minimum” cross section that requires a 2’ paved shoulder (now used in Maintenance of Traffic Alternative Analysis (MOTAA) and detailed design)
Off-Ramp-Capacity – Now explicitly looked for in MOTAA.

Slide 16

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

Historical wz crash analysis will be performed every two years seeking additional “lessons learned”.
Policies/standards/specifications will be changed as necessary to keep problems from happening again.

Slide 17

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Historical Crash Analysis

Hot off the presses – 2006 Historical Data Analysis has started…..
Emphasis on Fatalities and Fatal Crashes…..
Preliminary Information follows…..

Slide 18

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

2006 Historical Crash Analysis

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Slide 19

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

2006 Historical Crash Analysis

Of the total 110 fatal WZ crashes; 22 involved pedestrians as the victim (20%).

Slide 20

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

2006 Historical Crash Analysis

18 of the 22 pedestrians were construction workers (82%).
- 5 of the 18 were construction related vehicle running over the worker.
- 4 of the 18 were workers being inside the travel lane.
- 8 of the 18 were vehicles speeding, running off the road or driving through a coned off lane and striking a worker.
- 1 of 18 included a vehicle hitting a bucket truck and the worker fell out

Slide 21

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

2006 Historical Crash Analysis

17 of the fatal crashes were caused by vehicles not stopping when traffic was stopped in the traveling lanes (15%).

We’re not supposed to have backups?!?!?!

11 of the 17 were on Interstate routes.
3 of the 17 during morning peak hours
3 of the 17 occurred during the evening peak hours
6 of the 17 occurred at night (9:30 pm to midnight)

??? What the heck were we doing at this time of night???

2 of the 17 occurred midday
3 of the 17 occurred due to vehicles not stopping for equipment in the travel lane.

Slide 22

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

2006 Historical Crash Analysis

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Slide 23

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time WZ Crash Data

630.1008 State Level Processes and Procedures
- “Shall use field observations, wz crash data….”
- “Shall continually pursue improvement of wz safety and mobility by analyzing work zone crash and operational data from multiple projects….”

Slide 24

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

Candidate projects identified in winter.
Coordinate w/local enforcement to have WZ crashes put aside for pickup twice/month. PHYSICALLY PICKING UP CRASH REPORTS IS THE ONLY METHOD THAT HAS WORKED.
Data base application automatically sorts crashes into ½ mile segments (geo – locate).
Compared to historical “non-construction” frequencies.
“Problem” locations investigated.

Slide 25

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

WARNING -This slide targeted to the computer enthusiasts

Data input into Access data base through data entry form.
Crash trends are sorted and analyzed using pivot tables/charts.
Individual queries created for each wz in Access data base file.
Excel (using visual basic coding) hits data base file and runs queries to refresh charts and graphs with latest data.

Slide 26

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

System is set up by start of construction season.
Once Set-up, the ONLY thing needed done is to input new crash data.
ALL CHARTS, GRAPHS, & DATA ARE GENERATED AUTOMATICALLY WITH THE PUSH OF A BUTTON – VERY COOL ……….

Slide 27

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

Main Screen

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Slide 28

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

Click to Access Data Entry Screen (note: There is an arrow on the slide pointing to the first button on the screen)

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Slide 29

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

Crash Report Data Entry Form

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Slide 30

ODOT’s WZ Process in Terms of the New Federal WZ Regulations

Real Time Crash Analysis

Application Outputs

Note: This slide has indicators pointing to the chart on the slide, highlighting that for Mile 16.2 to 16.99, the non work zone average number of crashes equals 21 over 7 months, while there were 48 crashes over 3 months when a work zone was in the same location.