Minnesota CHSP Update - Model Screening Process

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Minnesota CHSP Update-Model Screening Process

• Howard Preston, PE
• January 3, 2007

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Technical Overview - UPDATE

• Model Process Focus on District 3
• Document District 3 Crash Characteristics
• Disaggregate by Critical Emphasis Area
• Disaggregate by State vs. Local Road System
• Disaggregate by Counties With-in District 3
• Observations
• Next Steps

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Statewide Fatalities (2001-2005)
Total Fatalities 3,008
Total Vehicle Occupant Fatalities 2,429
Driver Behavior Based Emphasis Areas Driver Behavior Based Emphasis Areas
Unbelted (Based on Veh. Occ. Fatalities) 1,271 (52) 1
Alcohol-Related 1,068 (36) 2
Speeding-Related 850 (28) 5
Involved Drivers Under 21 718 (24) 6
Infrastructure Based Emphasis Areas
Single Vehicle ROR 965 (32) 4
Intersection 1,004 (33) 3
Head-On and Sideswipe 611 (20) 7
Emphasis Area Fatality Rank
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ATP 3 Fatalities (2001-2005)
Driver Behavior Based Emphasis Areas Driver Behavior Based Emphasis Areas Driver Behavior Based Emphasis Areas Driver Behavior Based Emphasis Areas Infrastructure Based Emphasis Areas Infrastructure Based Emphasis Areas Infrastructure Based Emphasis Areas
Total Fatalities Unbelted Alcohol-Related Speeding-Related Young Driver Involved Single Vehicle ROR Inter-section Head-on Sideswipe
Statewide 3,008 1,271 (52) 1,068 (36) 850 (28) 718 (24) 965 (32) 1,004 (33) 611 (20)

District 3 Total 581 265 (53) 232 (40) 146 (25) 144 (25) 221 (38) 182 (31) 166 (29)

State Trunk Highway 280 124 (50) 87 (31) 63 (23) 59 (21) 82 (29) 88 (31) 101 (36)

Local Roads 301 141 (57) 145 (48) 83 (28) 85 (28) 139 (46) 94 (31) 65 (22)
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Model Process
Universes of Possible Safety Strategies
Strategic Planning Process - Data Partner
Driven - Prioritization
Supplemental Implementation Analysis
Document Primary Contributing Factors
Mapping Exercise
State System
Local System
Driver Behavior - Seat Belts - Impaired -
Young Drivers - Aggressive Drivers
Infrastructure - Lane Departure - Intersections

• Enforcement
• Education

• Engineering
• EMS

• Data Systems

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Detailed Model Process (1 of 2)
Universes of Possible Safety Strategies
Strategic Planning Process - Data Partner -
Driven Prioritization
December 31, 2004
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DetailedModel Process (2 of 2)
Primary Contributing Factors
Driver Behavior - Seat Belts - Impaired -
Young Drivers - Aggressive Drivers Infrastructur
e - Lane Departure - Intersections
Factors
Mapping Exercise
Road Categories - Freeway - Expressway -
Conventional - Volume
Strategies
ATP 1
State System
ATP 2
Fatal Serious Injury Crashes
ATP 3
Intersection Control - Signal - Stop
ATP 4
ATP M
Local System
ATP 6
ATP 7
Location - Rural - Urban
ATP 8
July, 2007
October, 2006
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Model Surveying Process ATP 3PRIORITY
STRATEGIES

• See Handout

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Priority Facility Types State System - ATP 3
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Priority Facility Types State System - ATP 3
Facility Type Facility Type Facility Type Crash Data Filter Priority Types Priority Types Priority Types
Facility Type Facility Type Facility Type Crash Data Filter Number Rate Density
Rural Freeway Freeway ? ?
Rural Expressway Expressway ? ?
Rural 4-Lane Undivided 4-Lane Undivided
Rural 4-Lane Conventional 4-Lane Conventional ? ?
Rural 2-Lane ADT lt 1,500 ? ?
Rural 1,500 lt ADT lt 5,000 ?
Rural 5,000 lt ADT lt 8,000 ?
Rural ADT gt 8,000 ? ?
Urban Freeway Freeway
Urban Expressway Expressway
Urban 4-Lane Undivided 4-Lane Undivided
Urban 4-Lane Conventional 4-Lane Conventional ? ? ?
Urban 3-Lane 3-Lane
Urban 5-Lane 5-Lane
Urban 2-Lane ADT lt 1,500
Urban 1,500 lt ADT lt 5,000
Urban 5,000 lt ADT lt 8,000
Urban ADT gt 8,000
Number of Severe Crashes Crash Rates Crash
Density Crash Type
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Priority Strategies by Facility Type State System
ATP 3

• See Handout

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Local System Priorities by County -ATP 3

• See Handout

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Local System Priorities by County ATP 3
County Crash Data Filter Emphasis Area Emphasis Area Emphasis Area Emphasis Area Emphasis Area Emphasis Area Emphasis Area
County Crash Data Filter Under 21 Speed Alcohol Unbelted ROR Intersection Head-On
Benton ? ?
Cass ? ? ? ?
Crow Wing ? ? ? ?
Isanti ? ?
Kanabec ? ? ? ? ?
Mille Lacs ? ? ? ?
Morrison ? ?
Sherburne ?
Stearns ? ? ? ? ? ?
Todd ? ?
Wadena ? ?
Wright ? ? ? ? ?
Number and Rate of Severe Crashes
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Priority Strategies by County Local System ATP 3
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(No Transcript)
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Observations

• The crash data supports the previous selection of
  Critical Emphasis Areas
• Impaired Driving
• Safety Belt Usage
• Young Drivers
• Aggressive Drivers
• Lane Departures
• Intersections
• Driver Safety Awareness
• Data Information Systems

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Observations

• In ATP 3
• Distribution of fatalities among the CEAs is
  generally similar to statewide averages with the
  following exceptions
• Unbelted drivers
• Alcohol-related
• Young drivers
• Head-on crashes
• For each Emphasis Area, the number of fatalities
  on the local system exceeds the number on the
  state system, with one exception head-on
  sideswipe
• 48 of fatalities occur on the STH system and 52
  on the local system.

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Observations

• Approximately 60 of the factors contributing to
  fatal crashes are related to driver behavior.
• ATP 3 has the highest number of fatal crashes
  where total EMS response time exceeded 1 hour.
• These facts suggest the need for a balanced
  approach to safety investing in the Other Es
  (especially on the local system).

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Observations

• Severe crashes are far overrepresented on rural
  facilities.
• Severe crashes are overrepresented on 2-lane
  roads (both state and local) in ATP 3. However,
  there is no obvious priority based on volume
  categories.
• There are fewer severe crashes on multi-lane
  roads, however, the 10 fatal head-on crashes on
  the freeway system and 10 fatal road departure
  crashes on the expressway system are the highest
  of any ATP in the state.

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Observations

• The analysis of the factors contributing to
  severe crashes in ATP 3 suggest the following
  high-priority infrastructure based improvements
• Rural Freeways Expressways Median Barriers
• Rural Expressways Street lights, Indirect turn
  treatments in median cross-overs, Edgeline
  rumblestrips
• Rural 2-Lane State Highways Street lights,
  Centerline rumblestrips, Edgeline rumblestrips,
  Shoulder edge treatments
• Rural Local Highways Street lights, Enhanced
  pavement markings, Edgeline rumblestrips,
  Shoulder edge treatments
• These types of strategies would be most
  effectively deployed using a proactive (as
  opposed to reactive) approach.

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Next Steps

• Receive comments and revise the process as
  necessary.
• Apply the revised process to the other ATPs.
• Prepare a short list of the highest priority
  strategies for each ATP.