How to investigate a blackspotSemarang18th & 19th April 2012     Phillip Jordan, Consultant  Road Safety International Pty...
How to investigate a blackspotAims of this presentation:   to outline the blackspot investigation process   to encourage...
On Indonesian highways and roads:•   Many crashes – mainly motorcycles, pedestrians•   Road safety is a growing community ...
What is a Blackspot ?         A blackspot is a location on a road which has a high         number of crashes – fatal, seri...
What is a Blackspot ?For Indonesia we give:• 10 points for each fatal crash• 5 points for each serious casualty crash• 1 p...
Crash occursThe sequence of actions in the whole blackspot process
Police                reportCrash occurs
Police                reportCrash occurs             Stored in                         database
Police                reportCrash occurs             Stored in                         database                           ...
Police                reportCrash occurs             Stored in                         database                           ...
Police                   reportCrash occurs                     Stored in                                 database        ...
Police                         report Crash occurs                          Stored in                                     ...
Police                         report  Crash occurs                         Stored in                                     ...
Police                         report  Crash occurs                         Stored in                                     ...
Part D Road safety engineering processesBlackspot investigations   – 6 examples given
Steps in the blackspot process
To treat a blackspot:                         11 Establish a list of blackspots   – Search Police crash data for high cras...
Police can assist with blackspot identification                                Road safety engineering issues for         ...
Police can assist with blackspot identification                                Road safety engineering issues for         ...
Police can assist with blackspot identification                                Road safety engineering issues for         ...
To treat a blackspot:                         22 Obtain and read all Police crash report forms.   – Gain a “picture” of th...
To treat a blackspot:                            2a2aDraw a collision diagram.   –   Easy to do – but messy, so do a rough...
Draw Collision Diagram & Crash Factor Grid
Draw Collision Diagram & Crash Factor Grid
Draw Collision Diagram & Crash Factor Grid
To treat a blackspot:                         2b2b       Draw a crash factor grid (Matrix)     – Easy to do – use Microsof...
Draw Collision Diagram & Crash Factor Grid
Draw Collision Diagram & Crash Factor Grid                                                                                ...
Draw Collision Diagram & Crash Factor Grid    6            7               8              9            10           11    ...
Draw Collision Diagram & Crash Factor Grid
To treat a blackspot:                33 Diagnose the problem     Look at the Collision Diagram and the Crash Factor     Ma...
To treat a blackspot:                44 Inspect the site – at the time that the patterns of  crashes have happened!  If ni...
To treat a blackspot:             44 Be logical ......  Only use countermeasures that will reduce the crashes  (For exampl...
•Inspect site – day and night.•Assess likely causes.•You are like a doctor at thisstage – diagnosing your patientto prescr...
• If a patient visits a doctor, the doctor asks about his illness.• The doctor does not just guess about his illness – he ...
6       7        8          9        10      11     12      13      14                                 18.6    18.7     18...
Police can assist with blackspot information
Police can assist with blackspot information Police can assist with blackspot information
Tips for the site inspection• Visual deceit   – Not all drivers/riders see the road the same way.   – You need to try to l...
The driver’s view is straight ahead - but the road goes left!!Visual deceit                                               ...
The driver’s view is straight ahead - but the road goes left!!                               CRASHVisual deceit           ...
Pantura – East Java.How/ why has this barrier been damaged?Why would anyone run off the road here?
Think of this highway at night!Visual deceit
To treat a blackspot:                55 Develop countermeasures – talk with colleagues,  with DGLT, with Police     Keep s...
Your list of low cost countermeasuresSigns – warning, regulatory, directionLine markingDelineationShoulder sealingRoadside...
To treat a blackspot:     66 Design, and then cost the work  - Finalise the design  - Work out the cost of the proposal
To treat a blackspot:                   7&87     Write your blackspot report8     Send for approval for funding; put this ...
Steps in the blackspot process
Into the future – maybe 3 or 4 years – there  will be competition for funding within the  blackspot program. Then you will...
How will we determine cost and benefits?1 We need to know the benefits to be gained $2 We need to know the cost of the cou...
How will we determine cost and benefits?1 We need to know the benefits to be gained $   How many crashes do we expect to s...
How will we determine cost and benefits?2. We need to know the cost of the countermeasures $   This is something engineers...
How will we determine cost and benefits?1   After you have established countermeasures2   Get the Crash Reduction Factor (...
Example of calculating the benefit cost ratio To work out the BCR we need to know the benefits(in $) of the countermeasure...
Benefits - Indonesia needs to have atable that shows the Crash ReductionFactor for each countermeasure   What percentage o...
CRASH REDUCTION FACTORS
CRASH REDUCTION FACTORS
ROADSIDE HAZARD MANAGEMENTWire Rope Safety Barrier (WRSB)                           45%               20Guardrail         ...
If there were (say) 16 crashes at the location in 3 years –and 12 of these are motorcycle crashes - you would aim topreven...
If the cost to seal the shoulders is (say) IDR200,000,000The Benefit/Cost Ratio will be 4,000,000,000 / 200,000,000 BCR = ...
20:1 BCR is excellentBut for now – concentrate on developing themost suitable countermeasuresBCR’s will only be needed for...
Some Indonesian blackspots• Two blackspots at bridges – one rural, one  urban• One blackspot at a Y junction• A blackspot ...
Before
Recommended
Blackspot location          at Menteng loopBLACKSPOT LOCATION AT MENTENG LOOP
BlackspotLocation    AERIAL PHOTOGRAPH OF BLACKSPOT LOCATION IN MENTENG, CENTRAL JAKARTA
The visibility before going over the crest of the bridge is obstructed, and the driver has noinformation about the presenc...
This direction sign was too late for the road user whowants to turn left to Sumenep/Latuharhary.                          ...
The loop has very small radius. It is dangerous if a driver misjudges it and has a higherspeed than should be. The driver ...
The island is not quite visible at a distance. There is a problem ofdelineation. It needs more guide posts.               ...
MONAS     MONASMANGGARAI   SUDIRMAN   HARMONI   HARMONI SALEMBA                         KOTA      KOTA     RECOMMENDATION
MONAS                 HARMONI                 KOTA                 MANGGAR                 AI                 SALEMBARECOM...
MONASHARMONIKOTAMANGGARAISALEMBA      RECOMMENDATION
A Y JUNCTION AT NAGREG
COLLISION DIAGRAM
RECOMMENDATION
An existing length of National Highway
Recommended option to improve safety on that length of National Highway
Blackspot inspection – near the Mosque, Jambi By-Pass
Blackspot inspection – near the Mosque, Jambi By-PassBlackspot inspection – near the Mosque, Jambi By-Pass
Blackspot inspection – near the Mosque, Jambi By-PassBlackspot inspection – near the Mosque, Jambi By-Pass
RECOMMENDATIONS•   Repair pot holes•   Seal shoulders•   Install edge lines, centre line•   Install speed restriction sign...
Pantura (National Highway) Km 18.7                                     7 crashes in 12 months at U turn
7 crashes in 12 months at U turnPantura (National Highway) Km 18.7
What will you do to reduce thecrashes at this U turn on this busy,fast National Highway?
Blackspot investigations• The investigation team  should put itself in the  shoes of the road users...to  identify why som...
Blackspot investigationsAre very effective, and they save Indonesian lives
Questions welcome
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
2 the blackspot investigation process
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2 the blackspot investigation process

  1. 1. How to investigate a blackspotSemarang18th & 19th April 2012 Phillip Jordan, Consultant Road Safety International Pty Ltd
  2. 2. How to investigate a blackspotAims of this presentation:  to outline the blackspot investigation process  to encourage you to look for low cost, high benefit countermeasures  to show you some recent Indonesian blackspot investigations  to outline some of the lessons learnt
  3. 3. On Indonesian highways and roads:• Many crashes – mainly motorcycles, pedestrians• Road safety is a growing community concern.• Crash data – getting better and more accurate.• Few “champions” of road safety engineering – yet!• There is much to do to improve road safety.• We (engineers) should start by treating blackspots.• But limited experience with blackspot treatments.
  4. 4. What is a Blackspot ? A blackspot is a location on a road which has a high number of crashes – fatal, serious or minor. It may be an intersection or it may be a length of road. In Victoria (Australia) – it is 3 casualty crashes in 5 years. In 1980 when the Victorian blackspot program started – it was 12 casualty crashes in 3 years. There has been great success over 30 years.
  5. 5. What is a Blackspot ?For Indonesia we give:• 10 points for each fatal crash• 5 points for each serious casualty crash• 1 point for all other crashes• Any site with more than 15 points = blackspot• Any 1km length with more than 30 points/km = black length• This is the starting point as we sift through candidate sites.
  6. 6. Crash occursThe sequence of actions in the whole blackspot process
  7. 7. Police reportCrash occurs
  8. 8. Police reportCrash occurs Stored in database
  9. 9. Police reportCrash occurs Stored in database Data extracted
  10. 10. Police reportCrash occurs Stored in database Data extracted Diagnosis
  11. 11. Police reportCrash occurs Stored in database Data extracted Diagnosis develop countermeasures
  12. 12. Police report Crash occurs Stored in database Data extractedDesign, then audit Diagnosis Developand then build countermeasures
  13. 13. Police report Crash occurs Stored in databaseMonitor Data extractedDesign, then audit Diagnosis Develop and then build countermeasures
  14. 14. Police report Crash occurs Stored in database ?Monitor Data extractedDesign, then audit Diagnosis Develop and then build countermeasures
  15. 15. Part D Road safety engineering processesBlackspot investigations – 6 examples given
  16. 16. Steps in the blackspot process
  17. 17. To treat a blackspot: 11 Establish a list of blackspots – Search Police crash data for high crash frequency sites. – Seek one kilometre lengths with high numbers of crashes. – Talk with the Police, use local knowledge. Identify those intersections and lengths within each kilometre where it is known there have been many crashes. – Gather all the Police reports for the site – read them.
  18. 18. Police can assist with blackspot identification Road safety engineering issues for Indonesia
  19. 19. Police can assist with blackspot identification Road safety engineering issues for Indonesia
  20. 20. Police can assist with blackspot identification Road safety engineering issues for Indonesia
  21. 21. To treat a blackspot: 22 Obtain and read all Police crash report forms. – Gain a “picture” of the crash history of the site. – Work with Police – ask them for details of the crashes that may not be in the reports.
  22. 22. To treat a blackspot: 2a2aDraw a collision diagram. – Easy to do – but messy, so do a rough draft first – For each vehicle – draw an arrow to show its direction – Show m/c, pedestrians, cars, trucks, buses differently – Make sure that the point of impact is accurately shown
  23. 23. Draw Collision Diagram & Crash Factor Grid
  24. 24. Draw Collision Diagram & Crash Factor Grid
  25. 25. Draw Collision Diagram & Crash Factor Grid
  26. 26. To treat a blackspot: 2b2b Draw a crash factor grid (Matrix) – Easy to do – use Microsoft Excel if you have it. – Paper will also do. – For each crash – summarise all the known details in one column. – Add rows if extra information is known from the Police reports.
  27. 27. Draw Collision Diagram & Crash Factor Grid
  28. 28. Draw Collision Diagram & Crash Factor Grid DEMAK BLACKSPOT (JALAN SEMARANG - KUDUS 18-19KM) Crash Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 KM 18.2 18.3 18.3 18.3 18.5 18.6 18.7 18.7 18.7 18.7 18.7 18.7 18.7 18.8 18.8 18.8 19 19 Date 11/11/2011 24/03/2011 06/12/2011 23/02/2012 06/06/2011 11/04/2011 10/03/2012 10/07/2011 11/07/2011 27/02/2011 25/06/2011 19/08/2011 12/12/2011 10/07/2011 30/12/2011 31/12/2011 11/08/2011 29/01/2012 Time 14:30:00 16:30:00 15:30:00 07:00:00 07:50:00 06:15:00 21:45:00 02:00:00 13:30:00 15:00:00 16:30:00 07:30:00 13:00:00 10:30:00 00:15:00 12:30:00 08:15:00 10:00:00 Fatal 1 1 0 0 0 1 0 1 1 0 1 0 0 1 0 0 0 1 Serious Injury 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Light Injury 0 0 1 1 1 0 1 0 0 1 0 3 2 1 1 2 1 0Light Condition Weather Fine Fine windy Fine Fine Fine Fine Fine Fine cloudy Fine Fine Fine Fine Fine Fine Fine FineRoad Condition Good Good Good Good Good Good Good Good Good Good Good Good Good Good Good Good Good Good Vehicle 1 m/c m/c m/c m/c m/c m/c m/c Medium Truck Medium Truck m/c m/c m/c Unknown m/c m/c Heavy Truck Medium Truck Heavy Truck Vehicle 2 Unknown Trailer Truck Unknown m/c m/c m/c Mini Bus m/c m/c m/c Heavy Truck m/c m/c Vehicle 3 B double Truck Accident type 61 4 63 7 6 9 5 74 81 63 2 64 94 21 66 31 63 5Traffic controller 1 1 1 7 1 1 0 1 1 1 1 1 1 1 1 1 1 1 Type Jalan 2 2 2 1 1 7 1 2 2 2 8 3 2 2 2 2 3 1 Bentuk Jalan 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 7 CRASHES AT ONE LOCATION
  29. 29. Draw Collision Diagram & Crash Factor Grid 6 7 8 9 10 11 12 13 14 18.6 18.7 18.7 18.7 18.7 18.7 18.7 18.7 18.811/04/2011 10/03/2012 10/07/2011 11/07/2011 27/02/2011 25/06/2011 19/08/2011 12/12/2011 10/07/2011 06:15:00 21:45:00 02:00:00 13:30:00 15:00:00 16:30:00 07:30:00 13:00:00 10:30:00 1 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 3 2 1 Fine Fine Fine Fine cloudy Fine Fine Fine Fine Good Good Good Good Good Good Good Good Good m/c m/c Medium Truck Medium Truck m/c m/c m/c Unknown m/c m/c m/c Mini Bus m/c m/c 9 5 74 81 63 2 64 94 21 1 0 1 1 1 1 1 1 1 7 1 2 2 2 8 3 2 2 1 1 1 1 1 1 1 1 1
  30. 30. Draw Collision Diagram & Crash Factor Grid
  31. 31. To treat a blackspot: 33 Diagnose the problem Look at the Collision Diagram and the Crash Factor Matrix – are there any patterns? Day time vs night time? Wet vs dry? Type of crash - head on, or run-off-road etc Type of road user? Direction of travel?
  32. 32. To treat a blackspot: 44 Inspect the site – at the time that the patterns of crashes have happened! If night time – inspect at night!! Put yourself in the shoes of the people who had the crashes. Ask - Why did they have their crash?
  33. 33. To treat a blackspot: 44 Be logical ...... Only use countermeasures that will reduce the crashes (For example, if crashes happened mainly during daytime, do not install street lighting as a countermeasure). $$ are always limited – so look first for low cost options. (Don’t use a bomb to kill a mouse).
  34. 34. •Inspect site – day and night.•Assess likely causes.•You are like a doctor at thisstage – diagnosing your patientto prescribe the best medicine!
  35. 35. • If a patient visits a doctor, the doctor asks about his illness.• The doctor does not just guess about his illness – he does not want totreat the patient for a headache when he has a heart problem.• You are like a doctor at this stage – diagnosing your blackspot!• The blackspot cannot speak – you have to look, listen and ask locals.• This takes time, skill, patience and logic
  36. 36. 6 7 8 9 10 11 12 13 14 18.6 18.7 18.7 18.7 18.7 18.7 18.7 18.7 18.8 11/04/2 10/03/2 27/02/2 25/06/2 19/08/2 12/12/2 10/07/2 011 012 10/07/2011 11/07/2011 011 011 011 011 011 06:15:0 15:00:0 16:30:0 07:30:0 10:30:0 0 21:45:00 02:00:00 13:30:00 0 0 0 13:00:00 0 1 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 3 2 1 Fine Fine Fine Fine cloudy Fine Fine Fine Fine Good Good Good Good Good Good Good Good Good Medium Medium Unkno m/c m/c m/c m/c m/c m/c Truck Truck wn Mini m/c m/c m/c m/c Bus 9 5 74 81 63 2 64 94 21 1 0 1 1 1 1 1 1 1 7 1 2 2 2 8 3 2 2 1 1 1 1 1 1 1 1 1 Review the Collision Diagram Review the Crash Factor Grid Use these on-site to help decide what countermeasures are needed
  37. 37. Police can assist with blackspot information
  38. 38. Police can assist with blackspot information Police can assist with blackspot information
  39. 39. Tips for the site inspection• Visual deceit – Not all drivers/riders see the road the same way. – You need to try to look at the road as others “might”
  40. 40. The driver’s view is straight ahead - but the road goes left!!Visual deceit USA - RHS
  41. 41. The driver’s view is straight ahead - but the road goes left!! CRASHVisual deceit LHS
  42. 42. Pantura – East Java.How/ why has this barrier been damaged?Why would anyone run off the road here?
  43. 43. Think of this highway at night!Visual deceit
  44. 44. To treat a blackspot: 55 Develop countermeasures – talk with colleagues, with DGLT, with Police Keep simple, keep low cost Persevere – there will be many locations where suitable countermeasures will be possible.
  45. 45. Your list of low cost countermeasuresSigns – warning, regulatory, directionLine markingDelineationShoulder sealingRoadside hazard removalGeometric changesSpeed limitsTraffic signalsRoundaboutsLighting
  46. 46. To treat a blackspot: 66 Design, and then cost the work - Finalise the design - Work out the cost of the proposal
  47. 47. To treat a blackspot: 7&87 Write your blackspot report8 Send for approval for funding; put this site into the Works Program Ensure to implement the agreed countermeasures(s). It is no use for the road users unless we make positive changes to the location.
  48. 48. Steps in the blackspot process
  49. 49. Into the future – maybe 3 or 4 years – there will be competition for funding within the blackspot program. Then you will have to rank sites so that funds are spent on those sites that will return the “best value” to the people of Indonesia
  50. 50. How will we determine cost and benefits?1 We need to know the benefits to be gained $2 We need to know the cost of the countermeasures $3 Then we calculate the benefit/ cost ratio
  51. 51. How will we determine cost and benefits?1 We need to know the benefits to be gained $ How many crashes do we expect to save, and how much does each one cost?
  52. 52. How will we determine cost and benefits?2. We need to know the cost of the countermeasures $ This is something engineers are good at calculating.
  53. 53. How will we determine cost and benefits?1 After you have established countermeasures2 Get the Crash Reduction Factor (% from list)3 Have a crash cost ($)4 Work out the value of the benefits of the countermeasures ($)5 Calculate the cost of the works ($)6 Calculate the benefit/ cost ratio
  54. 54. Example of calculating the benefit cost ratio To work out the BCR we need to know the benefits(in $) of the countermeasures, and the cost (in $) of the countermeasures.
  55. 55. Benefits - Indonesia needs to have atable that shows the Crash ReductionFactor for each countermeasure What percentage of crashes at the blackspot will be reduced if we seal the shoulders of the highway for one kilometre?
  56. 56. CRASH REDUCTION FACTORS
  57. 57. CRASH REDUCTION FACTORS
  58. 58. ROADSIDE HAZARD MANAGEMENTWire Rope Safety Barrier (WRSB) 45% 20Guardrail 35% 20Median barriers (any type including centreline WRSB) 20% 20Guard rail at culvert 25% 20Guardrail for bridge end post 20% 20Crash Cushions 15% 20PEDESTRIANS & CYCLISTSRefuges, Channelisation, Kerb extension 30% 20Pedestrian signals 25% 15Bicycle paths, threshold treatments 10% 20Upgrade pedestrian signals 20% 15Pedestrian overpass 10% 20MOTORCYCLISTSNew roundabouts 75% 20Intersection signal remodel 50% 15Fully Controlled Right Turn 55% 15Shoulder sealing 50% 20STREET LIGHTINGProvision of street lighting general 25% 15Improve lighting at intersections 25% 15Improve lighting at roadway segment 25% 15Improve lighting at PEDESTRIAN CROSSING 40% 15Improve lighting at railway crossing 10% 15 Crash reduction factors based on real experience from the Victorian (Australia) blackspot program since 1980
  59. 59. If there were (say) 16 crashes at the location in 3 years –and 12 of these are motorcycle crashes - you would aim toprevent 50% of these 12 crashes in the next 3 years – thatis 6 crashes in the next 3 years If each crash costs IDR100,000,000 – you will claim benefits of IDR600,000,000 over 3 years – or IDR 4,000,000,000 for the life of 20 years Benefits = IDR4,000,000,000 Crash reduction factors based on real experience from the Victorian (Australia) blackspot program since 1980
  60. 60. If the cost to seal the shoulders is (say) IDR200,000,000The Benefit/Cost Ratio will be 4,000,000,000 / 200,000,000 BCR = 20.0 This project will be compared with all other blackspots in your Balai – those with the highest BCR’s will be treated first. The others will wait for next year.....
  61. 61. 20:1 BCR is excellentBut for now – concentrate on developing themost suitable countermeasuresBCR’s will only be needed for new blackspotsafter a few more years time
  62. 62. Some Indonesian blackspots• Two blackspots at bridges – one rural, one urban• One blackspot at a Y junction• A blackspot at a small cross road intersection in a small town• A blacklength on a Highway in Sumatra• A black spot on a curve on a By-Pass
  63. 63. Before
  64. 64. Recommended
  65. 65. Blackspot location at Menteng loopBLACKSPOT LOCATION AT MENTENG LOOP
  66. 66. BlackspotLocation AERIAL PHOTOGRAPH OF BLACKSPOT LOCATION IN MENTENG, CENTRAL JAKARTA
  67. 67. The visibility before going over the crest of the bridge is obstructed, and the driver has noinformation about the presence of loop in front. The driver may know the road has fourlanes , but the first and second lane are forced to turn left.
  68. 68. This direction sign was too late for the road user whowants to turn left to Sumenep/Latuharhary. 78
  69. 69. The loop has very small radius. It is dangerous if a driver misjudges it and has a higherspeed than should be. The driver need to be warned with a speed limit of 30 km/hr. RECOMMENDATION
  70. 70. The island is not quite visible at a distance. There is a problem ofdelineation. It needs more guide posts. RECOMMENDATION
  71. 71. MONAS MONASMANGGARAI SUDIRMAN HARMONI HARMONI SALEMBA KOTA KOTA RECOMMENDATION
  72. 72. MONAS HARMONI KOTA MANGGAR AI SALEMBARECOMMENDATION
  73. 73. MONASHARMONIKOTAMANGGARAISALEMBA RECOMMENDATION
  74. 74. A Y JUNCTION AT NAGREG
  75. 75. COLLISION DIAGRAM
  76. 76. RECOMMENDATION
  77. 77. An existing length of National Highway
  78. 78. Recommended option to improve safety on that length of National Highway
  79. 79. Blackspot inspection – near the Mosque, Jambi By-Pass
  80. 80. Blackspot inspection – near the Mosque, Jambi By-PassBlackspot inspection – near the Mosque, Jambi By-Pass
  81. 81. Blackspot inspection – near the Mosque, Jambi By-PassBlackspot inspection – near the Mosque, Jambi By-Pass
  82. 82. RECOMMENDATIONS• Repair pot holes• Seal shoulders• Install edge lines, centre line• Install speed restriction signs• Cut back vegetation to increase sight lines
  83. 83. Pantura (National Highway) Km 18.7 7 crashes in 12 months at U turn
  84. 84. 7 crashes in 12 months at U turnPantura (National Highway) Km 18.7
  85. 85. What will you do to reduce thecrashes at this U turn on this busy,fast National Highway?
  86. 86. Blackspot investigations• The investigation team should put itself in the shoes of the road users...to identify why some of them are have crashes at the site.
  87. 87. Blackspot investigationsAre very effective, and they save Indonesian lives
  88. 88. Questions welcome
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