OHIO PLANNING CONFERENCE • JULY 18, 2018
BETTER S BETTER S AFE THAN S AFE THAN S ORRY: ORRY: Navigating Data-Driven S Navigating Data-Driven S afety afety Analysis (DDS Analysis (DDS A) A) Derek Troyer, PE Kendra S chenk, PE, PTOE
AGENDA o What is DDS A? o Why does it matter? o What are the Impacts? o Breaking Down the Charts o Interpreting Results
DATA DRIVEN S AFETY ANALYS IS S afety Analysis for All Proj ects o Process developed to right size the level of safety analysis based on proj ect type Fewer More Better Fatalities Informed Targeted Decision & Serious Investments Making Injuries 4
IT MATTER WHY DOES
CRAS H TRENDS Ohio has experienced four years of rising traffic deaths.
UNDERS TANDING EXIS TING S ITE PERFORMANCE Review statewide or regional o priority list INCREAS Previous safety reviews of the o location or proj ect ED COMPLEXITY Review of observed crash o trends Use analysis procedures o included in the AAS HTO Highway S afety Manual
US ES FOR DDS A o Evaluate safety performance to know how it compares to peer sites or other alternatives being evaluated o Targeting investments where there is a potential to reduce crashes
? WHAT ARE THE IMPACTS
LOCATION AND DES IGN MANUAL Added Crash Analysis requirement in 2016 Review state and regional priority list Research previous safety analysis Review observed crash data Document Crash Patterns that exist o
PROJECT S COPE Requires the Crash Analysis be completed prior to scoping the proj ect Improved S coping o Identify potential funding sources o Elements included in the Project Initiation Package (PIP)
DEVELOPING PURPOS E AND NEED Purpose and Need statements are important o Only include safety considerations when there is a documented crash pattern or site is performing worse than its peers o Additional analysis will be required if safety is included in the P&N
FEAS IBILITY S TUDY (ALTERNATIVES ANALYS IS ) Quantify your safety performance Mirroring the capacity analysis process Analyze existing conditions o Analyze each build alternative o Compare results o
PROJECT DES IGN Use knowledge gained from the feasibility study Identify proj ect elements sensitive to crash frequency variation o Offsets to barrier o S ignal operation o Lane width
LOCAL GOVERNMENTS Can apply same procedures on local proj ects Alternatives evaluation o Potential for cost savings o Implement countermeasures as part of proj ect o
PDP PROJECTS
BREAKING DOWN THE CHARTS
BREAKING DOWN THE CHARTS PDP Paths 1 and 2 o (No Alternative Analysis) Source: Montgomery, Ohio Source: Highland County, Ohio Source: Butler County, Ohio
BREAKING DOWN THE CHARTS o PDP Paths 3, 4, & 5 (Alternatives Analysis) o PDP Paths 3, 4, & 5 (Alternatives Analysis)
MENT S ES S AFETY AS MINIMAL S
IP MAP ON ODOT S DETERMINE IF LOCATION IS
IP MAP ON ODOT S DETERMINE IF LOCATION IS
MENT S ES S AFETY AS MINIMAL S
TS AFETY PRIORITY LIS DETERMINE RANKING ON S
TS AFETY PRIORITY LIS DETERMINE RANKING ON S
TS AFETY PRIORITY LIS DETERMINE RANKING ON S
TS AFETY PRIORITY LIS DETERMINE RANKING ON S
MENT S ES S AFETY AS MINIMAL S
ANALYZE HIS TORICAL/ OBS ERVED CRAS H DATA Most Recent 3- Years of Crash Data
ANALYZE HIS TORICAL/ OBS ERVED CRAS H DATA Total Rear End Crashes Inj ury Rear End Crashes (Compared t o Inj ury % for Multi-Vehicle Crashes) Below S tatewide Average S tatewide Average Angle Crashes Above Statewide Average (Including Left-Turn Crashes) Sideswipe Crashes 0% 10% 20% 30% 40% 50% 60% 70% 80%
MENT S ES S AFETY AS MINIMAL S
PDP PATHS 1 & 2 o Very little analysis o “ If it ain’ t broke, don’ t fix it” o Could mitigate lower- ranking safety hot spots
PDP PATHS 3, 4, & 5 (NO S AFETY COMPONENT) Use existing crash data in alternatives HSM analysis Do not use existing crash data in alternatives HSM analysis
PDP PATHS 3, 4, & 5 (S AFETY COMPONENT) Perform HSM analysis to establish baseline conditions Use existing crash data in alternatives HSM analysis Do not use existing crash data in alternatives HSM analysis
INTERPRETING ULTS RES
INTERPRETING RES ULTS Alternative A Alternative B LOS D C Queue Length Reductions 10% 40% R/ W Impacts None 2 parcels Construction Costs $300,000 $750,000 Crash Reductions 2 crashes/ year 6 crashes/ year 1 inj ury crash/ year 0.5 inj ury crash/ year
INTERPRETING RES ULTS I-670/ I-270 INTERCHANGE ANALYS IS NORTH TO DOWNTOWN TO EASTON ALTERNATIVE 1
INTERPRETING RES ULTS I-670/ I-270 INTERCHANGE ANALYS IS ALTERNATIVE 2 TO X ALTERNATIVE 3 TO TO
INTERPRETING RES ULTS I-670/ I-270 INTERCHANGE ANALYS IS o No Build 9 freeway segments o 3 ramp segments o 5.69 miles o o Build 14 freeway segments o 3 ramp segments o 8.00 miles o
INTERPRETING RES ULTS I-670/ I-270 INTERCHANGE ANALYS IS
INTERPRETING RES ULTS I-670/ I-270 INTERCHANGE ANALYS IS +20% 120.06 114.27 140 +25% ear 120 95.54 Predicted Crash Frequency per Y 84.89 80.65 100 66.05 80 60 40 15.89 15.20 14.39 13.76 13.86 12.01 4.90 4.65 3.62 20 0 KA B C O TOTAL No Build Alt 2 Alt 3
I-670/ I-270 INTERCHANGE ANALYS INTERPRETING RES Predicted Crash Frequency per Y ear per Mile 10 12 14 16 18 0 2 4 6 8 0.64 KA 0.61 0.58 2.11 No Build 1.80 B ULTS 1.72 2.44 Alt 2 1.99 C 1.90 11.61 IS Alt 3 10.61 O 10.08 16.79 TOTAL 15.01 14.28
MARTLANE ULTS INTERPRETING RES MARTLANE I-670 S I-670 S
INTERPRETING RES ULTS I-670 S MARTLANE Initial HS M Analysis Results KA B C O Total No Build 6.5 22.0 23.2 137.1 188.9 Build 7.1 23.1 24.3 142.0 196.5 Difference +0.6 +1.1 +1.1 +4.9 +7.6 (8% ) (5% ) (5% ) (4% ) (4% ) *BASED ON WEIGHTED VOLUME ANALYSIS OF WHEN SMARTLANE IS OPERATIONAL AND WHEN IT IS CLOSED
INTERPRETING RES ULTS I-670 S MARTLANE Countermeasures to prevent fixed object crashes WIDER EDGE LINE RUMBLE STRIPS
INTERPRETING RES ULTS I-670 S MARTLANE Final HS M Analysis Results (With Countermeasures) KA B C O Total No Build 6.5 22.0 23.2 137.1 188.9 Build 5.7 18.5 19.5 142.0 185.7 Difference -0.8 -3.5 -3.7 +4.9 -3.2 (13% ) (16% ) (16% ) (4% ) (2% ) *BASED ON WEIGHTED VOLUME ANALYSIS OF WHEN SMARTLANE IS OPERATIONAL AND WHEN IT IS CLOSED
INTERPRETING RES ULTS I-670 S MARTLANE o S afety is j ust one metric to help make the best decision o More to the results than meets the eye
S UMMARY o S afety should be incorporated into all proj ects – ODOT policy changes o Cost savings could be identified from safety analysis o S afety can be used as a qualitative metric to evaluate alternatives
Derek Troyer, PE Ohio DOT 614.387.5164 Derek.Troyer@ dot.ohio.gov Kendra S chenk, PE, PTOE Burgess & Niple 614.459.2050 Kendra.S chenk@ BurgessNiple.com
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