Conference PaperPDF Available

Brunei iRAP -Speed Management and Infrastructure Improvements

Authors:

Abstract and Figures

Brunei have made considerable investment in improving the design and safety of their road transport infrastructure over the last 20 years. Like almost all countries, Brunei (on the island of Borneo) are still not happy with the level of road trauma (fatal and serious injury crashes) on their roads and the impact this has on families and communities. In 2014 they decided to undertake an iRAP assessment of their strategic routes (just over 500km of their network) to determine what else could be done to reduce road trauma. The findings of the iRAP assessment did indicate that Brunei has a relatively safe network, compared with other ASEAN and developed countries. Around 45% of all roads (urban and rural) and 63% of highways (rural/high speed) had a three star rating or better (the rating varies from one star which is poor to five star which is excellent). Two safety road investment program (SRIP) scenarios were developed using the VIDA (iRAP) analysis tool. Scenario One includes infrastructure upgrades with a cost of at least BND$42M. Scenario One, when fully implemented, is expected to increase the number of 3 star plus roads to 85%. Scenario Two includes both speed management (reducing operating speeds by typically 5 to 10km/h on all highways and main roads) and infrastructure upgrades. The infrastructure upgrades will be at least BND$36M. Scenario Two, when fully implemented, is expected to increase the number of 3 star plus roads to over 95%. Brunei is one country where a minimum three star rating for all highways and strategic main roads is within reach.
Content may be subject to copyright.
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
Brunei iRAP Speed Management and Infrastructure Improvements
1
Shane1 Turner1a, Mike2 Smith2b, Marc3 Robson3a
2
aNational Road Safety Specialists, MWH Global (now part of Stantec) New Zealand 1 & 2b, Team Leader,
3
MWH Global (now part of Stantec) Brunei 3
4
Abstract
5
Brunei have made considerable investment in improving the design and safety of their road
6
transport infrastructure over the last 20 years. Like almost all countries, Brunei (on the island of
7
Borneo) are still not happy with the level of road trauma (fatal and serious injury crashes) on their
8
roads and the impact this has on families and communities. In 2014 they decided to undertake an
9
iRAP assessment of their strategic routes (just over 500km of their network) to determine what else
10
could be done to reduce road trauma. The findings of the iRAP assessment did indicate that Brunei
11
has a relatively safe network, compared with other ASEAN and developed countries. Around 45%
12
of all roads (urban and rural) and 63% of highways (rural/high speed) had a three star rating or
13
better (the rating varies from one star which is poor to five star which is excellent). Two safety road
14
investment program (SRIP) scenarios were developed using the VIDA (iRAP) analysis tool.
15
Scenario One includes infrastructure upgrades with a cost of at least BND$42M. Scenario One,
16
when fully implemented, is expected to increase the number of 3 star plus roads to 85%. Scenario
17
Two includes both speed management (reducing operating speeds by typically 5 to 10km/h on all
18
highways and main roads) and infrastructure upgrades. The infrastructure upgrades will be at least
19
BND$36M. Scenario Two, when fully implemented, is expected to increase the number of 3 star
20
plus roads to over 95%. Brunei is one country where a minimum three star rating for all highways
21
and strategic main roads is within reach.
22
Introduction
23
Deaths and injuries from road vehicle crashes are a major and growing public health epidemic. Each
24
year 1.3 million people die and a further 50 million are injured or permanently disabled in road
25
crashes. Road crashes are now the leading cause of death for children and young people aged
26
between 10 and 24. The burden of road crashes is comparable with malaria and tuberculosis and
27
costs 1-3% of the world’s GDP (Geneva, WHO, 2009).
28
While the number of fatal and serious injury crashes in Brunei (at around 100 per year) are
29
relatively low compared with the global figures, the grief and suffering caused by road crashes still
30
has a major impact on families and communities within this small country of around 400,000
31
residents. Hence the strong desire by the Government to continue to drive down the number of
32
fatalities and serious injuries (hospitalisations). A key element of this commitment has been the
33
major investment in highway infrastructure over the last twenty years. The other key areas of focus
34
being safer road users and safer vehicles. With a relatively young vehicle fleet Brunei does benefit
35
from improvements in vehicle safety. Driver behaviour still needs further attention, particularly
36
around speeding and seatbelt wearing.
37
Given the high investment in infrastructure over the last twenty years it is important to understand
38
the level of safety the current highway network provides and what further work could be done to
39
reduce crash rates further. The iRAP road assessment approach is an excellent way of
40
understanding the crash risks along the strategic road network and targeting improvements that
41
address these risks. Of particular interest in Brunei is the high operating speeds on urban roads,
42
given the relatively high speed limits, and many drivers travelling above these speed limits.
43
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
The iRAP package of tools includes the development of safer roads investment programme (SRIPs)
44
to lower crash risks further. This normally focuses on infrastructure improvements. In the case of
45
Brunei the investment program also included speed management. Initially it is suggested that a
46
speed management program focuses on getting drivers to travel within the current speed limits,
47
before considering whether the speed limits themselves need to be lowered.
48
This paper first outlines the iRAP process before presenting details on the 2014 safety performance
49
of just over 500km of both urban and rural single and dual carriageway highways and main roads in
50
Brunei. It then presents two safety improvement upgrade scenarios that are expected to reduce
51
serious and fatal crashes significantly across this strategic road network.
52
International Road Assessment Programme (iRAP)
53
The International Road Assessment Programme (iRAP - www.irap.org) has drawn upon the
54
extensive knowledge base of the developed world’s Road Assessment Programmes (EuroRAP,
55
AusRAP and usRAP), to develop a road survey methodology for all countries. This Star Rating
56
methodology does not require detailed crash data and works directly from road surveys. The
57
iRAP approach has been applied in over 70 countries.
58
The iRAP Protocol used internationally has four stages:
59
1. Risk Maps; where detailed crash data is available maps can illustrate the actual number
60
of deaths and injuries on a road network (good quality data is not readily available in
61
Brunei).
62
2. Star Ratings provide a simple and objective measure of the level of safety provided by
63
a road’s design.
64
3. Safer Roads Investment Plans draw on approximately 90 proven road improvement
65
options to generate affordable and economically sound infrastructure options for saving
66
lives. Multiple investment plans should be created with different scenarios and goals to
67
highlight the beneficial aspects of each and drive a forwards work programme to
68
improve road safety.
69
4. Performance Tracking enables the use of Star Ratings and Risk Maps to track road
70
safety performance and establish policy positions.
71
Star Ratings provide a simple and objective measure of the relative level of risk associated with
72
road infrastructure for an individual road user. 5-star (green) roads are the safest, while 1-star
73
(black) roads are the least safe. Figure 1 shows photo examples of the various star rating levels.
74
Notice that the location and type of road-side hazards and presence of shoulder is important in
75
the ‘vehicle’ star rating. For the higher standard roads both shoulder and median barriers are
76
provided from extra protection of drivers. Importantly, Star Ratings can be produced without
77
reference to detailed crash data.
78
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
79
80
81
Figure 1 - Examples of different Vehicle Star Rating roads (Malaysia, source iRAP website)
82
iRAP Star Ratings are based on the engineering features of the road and the degree to which they
83
impact on the likelihood and severity of crashes (see Figure 2). Data on engineering features are
84
coded at 100m intervals along the surveyed roads. The focus is on the features that influence the
85
most common and severe types of road crash for motor vehicles, motorcyclists, pedestrians and
86
bicyclists. The volume and speed of vehicles is also a key factor in crash occurrence.
87
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
88
Figure 2 Main crash types considered for each mode and example of crash variables examined
89
- in this case for pedestrians walking alongside road (source iRAP website)
90
Brunei iRAP Data Collection
91
The surveyed network consisted of 535 km of strategic routes and main arterials (single and
92
dual carriageway). These roads were selected by the Brunei Department of Roads and were
93
surveyed between 3rd and 16th of December 2014. The location of roads surveyed in Brunei
94
(which is a small country in the northern part of the island of Borneo) are shown in Figure 4.
95
The main highway /motorway travels along the coast (the bottom left of the diagram to the top
96
right). The separate section of black and red highways is in the Tempurong (popular for eco-
97
tourism) region which is separated from the other regions of Brunei (Muara, Tutong and Belait)
98
by part of the Malaysia state of Sarawak. Access to this area is by boat or car through Sarawak.
99
100
Figure 4 - Strategic Brunei Road Network (surveyed)
101
Dual carriageway roads have been surveyed in both directions. The surveyed network includes
102
approximately 10% of all roads in Brunei, and the majority of the strategic and high volume urban
103
and high speed routes. All the countries motorways and highways are included.
104
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
To calculate the Star Rating of each section of route the entire survey network was videoed, and
105
from this feature data has been coded at 100m intervals. In excess of 60 speed and traffic volume
106
counts were collected (for a representative sample of routes), as this data was not readily available.
107
Countermeasure costs were estimated using Malaysia unit construction costs. The crash saving
108
benefits for each serious and fatal crash were collated (based on willingness to pay for fatalities).
109
Aggregated crash data was also provided for the last two years to calibrate the iRAP model to
110
Brunei conditions.
111
The predicted distribution of fatal and serious crashes across the Brunei network is expected to
112
decreases by around 60-65% for each improvement in Star Rating band (e.g. upgrading a road from
113
the middle of the 2 star band to the middle of the 3 star band will reduce fatal and serious injury
114
crashes by around 60 to 65%). A four star road is predicted to have between 80% and 90% less fatal
115
and serious injury crashes (per user) than a two star road (full 2 band shift). So an improvement in
116
star ratings of one and two star roads can lead to a major difference in the number of serious injury
117
and fatal crashes.
118
While motor vehicle occupants are the primary mode of transportation in Brunei, pedestrians,
119
bicyclists, and motorcyclists star ratings were developed so that this can be considered in the design
120
of new roads and safety improvements. The weight being placed on a safer design for each mode
121
should reflect the likely future use of each corridor. Hence routes that may be promoted for bicycle
122
use need a better star rating for bicycles compared with those where cycling is less likely.
123
The goal being to increase the proportion of trips by each mode that occur on higher star rated
124
roads.
125
Current Performance of Network
126
Table 1 shows the star rating table for all four road user types, vehicle occupants, pedestrians,
127
bicyclists, and motorcyclists. Figure 6 and 7 show the star rating maps for vehicle occupants and
128
pedestrians (showing facility ratings only in areas pedestrians were observed). The star rating of
129
the road, both urban and rural, in Brunei compares well with those of other developed countries
130
and generally above that of other ASEAN countries. It shows that 45% of strategic roads have a
131
star rating of three or better for vehicle occupants. Further investigation indicates that 63% of
132
motorways have three star or better.
133
A review of the star rating scores indicate that the proportion of roads that have three stars for
134
vehicle occupants, and particularly urban roads, would increase markedly if the high operating
135
speeds on Brunei roads could be reduced. The infrastructure for walking, cycling and motor-
136
cycling is fairly poor. Fortunately there are few serious and fatal crashes involving these modes.
137
But some routes are used by these modes, and should have better infrastructure provided.
138
Pedestrians can be protected through the provision of safe crossing places such as at signalised
139
crossings and overpasses, and protected at mid-point locations through wider and increased
140
separation of footpaths and pedestrian fencing.
141
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
142
Table 1 2014 Star Ratings Table
143
144
Figure 5 - Vehicle Occupant Star Rating Map (smoothed)
145
146
Figure 6 - Pedestrian Star Rating Map (smoothed)
147
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
Safer Road Investment Programmes (SRIPs)
148
A Safer Roads Investment Plan (SRIP) shows a list of affordable and economically sound
149
road safety treatments (or countermeasures), specifically tailored to reduce risk on the surveyed
150
network (see Figure 7 for examples). Each countermeasure proposed in the SRIP is
151
supported by strong evidence that, if implemented, it will prevent deaths and serious injuries in a
152
cost-effective way, i.e. it is suggested that the countermeasures listed will save more in crash
153
costs prevented than it costs to construct and maintain the feature. Nevertheless, each
154
countermeasure should be regarded as a recommendation only for further investigation and must
155
be subject to additional prioritisation, concept planning and detailed design before
156
implementation. Although the results shown here were generated using a cost-benefit ratio (BCR)
157
threshold of 3 (only treatments that return benefits three times their implementation cost or
158
better); this cut-off can be increased in order to produce a smaller and less costly programme of
159
works, or decreased in order to produce a larger and more costly programme of works, to suit
160
the available budget. The countermeasure unit costs are currently based on Malaysian
161
construction costs.
162
163
Figure 7 Examples of proven road safety treatments/countermeasures
164
Two scenarios have been run to produce two different SRIP, with different costs and outcomes. A
165
scenario involves the application of a series of countermeasures to the surveyed (or baseline) road
166
network. For each scenario the reduction in fatal and serious crashes (for a given cost) is predicted.
167
The crash reduction is the sum of crash reduction benefits of a large number of upgrade treatments.
168
The unit treatment costs are currently based on Malaysian unit costs for each treatment type
169
converted into Brunei dollars.
170
Scenario 1 - Infrastructure Improvements Only
171
The first scenario includes a number of road safety treatments that have at least an initial cost-
172
benefit ratio of 3 or higher and no change in operating speed for each speed limit and road type. The
173
treatments are generated by algorithms in the VIDA tool, which is the platform that the iRAP
174
organisation has produced for storing and analysing iRAP data for each country that has collected
175
this information. The treatment analysis tool (in VIDA) looks at each road deficiency (that leads to
176
a lower star rating) and look at the range of improvement options that could be implemented to
177
address that deficiency. For example shoulder barriers can be implemented to prevent drivers going
178
into hazardous road-sides. It selects those treatments that have a cost-benefit ratio (crash saving
179
benefits divided by treatment costs) that is at or above the cut-off. In this case the BCR cut-off is 3
180
or more.
181
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
The Safer Roads Investment Plan (SRIP) for Scenario One includes various works, the most
182
effective and prolific are:
183
25 km of road duplication and central median barrier mostly on the Rasau Bypass this cost
184
appears low but has a programme BCR provisionally of six
185
128 km of roadside barrier and 151 km of roadside hazard removal roadside hazards
186
contribute significantly to crash severity, hazard protection through semi-rigid barrier
187
systems is often more effective than clear-zone work through hazard removal
188
73 km of high fiction surfacing road surfacing quality was based on a brief visual
189
inspection rather than a measured process and so surfacing condition within iRAP is not
190
necessary representative of actual skid resistance available
191
314 km of shoulder rumble strips rumble strips provide audio and tactile awareness to
192
vehicle drivers that they are straying from the traffic lanes. Centreline rumble strips are
193
effective low cost short term treatments prior to duplication or a central median barrier
194
73 km of route and curve delineation
195
Table 2 shows the star rating that are expected when Scenario One is fully implemented. This
196
proposed scenario is estimated to reduce deaths and hospitalisations by 20 annually including
197
approximately 7 fatalities. A total of approximately BND$250M in safety benefits over 20 years for
198
a capital expenditure in excess of BND$43M and an overall cost-benefit ratio of 6.
199
Under this scenario the length of road with a (vehicle occupant) star rating of three or more
200
improves from 45% to 85% of the surveyed network. This includes 20% of the road length being
201
rated at four or five stars. Approximately 90% of vehicle kilometres travelled would be on three or
202
higher star roads and 25% of vehicle kilometres would be on four and five star roads. The length of
203
roads with one star is very low and two star is less than 20%.
204
205
Table 2 - Scenario One Star Ratings Table
206
Scenario 2 Speed Management and Infrastructure Improvements
207
In Scenario 2 both speed management and infrastructure treatments have been considered. Like
208
many countries in South East Asia speeding is a major issue in Brunei and it does have a big
209
bearing on the number of serious and fatal crashes. Table 3 shows the improvement in operating
210
speed (85th percentile and mean speeds) by speed limit that have been assumed for this scenario.
211
This reduction in operating speeds seems reasonable in the short to medium term. Ideally speeds
212
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
could be reduced further, especially in urban areas. Further refinement of this scenario (and the
213
assumed speed changes) would be undertaken once a speed management strategy has been
214
developed for Brunei. A speed management strategy needs to consider the level of investment in
215
education and enforcement that might be required to achieve particular operating speed targets.
216
Table 3. Maximum 85th percentile and mean speeds for various posted speed limits
217
Posted Speed
Limit
Reported Speed Range
Scenario 2 Maximum
Scenario 2
Maximum
85th
Mean
85th
Mean
85th
Speed
Reduction
50 km/h
80 km/h
65 km/h
95 km/h
75 km/h
55 km/h
65 km/h
30 km/h
65 (70) km/h
70 km/h
50 km/h
80 km/h
60 km/h
65 km/h
75 km/h
5 km/h
80 km/h
85 km/h
80 km/h
95 km/h
80 km/h
90 km/h
5 km/h
100 km/h
95 km/h
85 km/h
105 km/h
95 km/h
90 km/h
95 km/h
10 km/h
Once the operating speeds were adjusted, the iRAP tools (in VIDA) have been used to develop the
218
SRIP for the lower speed network based on a cost-benefit cut-off for each treatment of 3.
219
The SRIP for Scenario 2 includes various works, the most effective and prolific are:
220
25 km of road duplication and central median barrier mostly on the Rasau Bypass this cost
221
appears low but has a programme BCR provisionally of six
222
104 km of roadside barrier and 220 km of roadside hazard removal roadside hazards
223
contribute significantly to crash severity, hazard protection through semi-rigid barrier
224
systems is often more effective than clear zone work through hazard removal
225
60 km of high fiction surfacing road surfacing quality was based on a brief visual
226
inspection rather than a measured process and so surfacing condition within iRAP is not
227
necessary representative of actual skid resistance available
228
167 km of shoulder rumble strips rumble strips provide audio and tactile awareness to
229
vehicle drivers that they are straying from the traffic lanes. Centreline rumble strips are
230
effective low cost short term treatments prior to duplication or a central median barrier
231
56 km of route and curve delineation
232
Table 4 shows the overall changes in star rating of this scenario.
233
ARS Conference Full Paper Peer Review
Turner1 et al.
Proceedings of the 2016 Australasian Road Safety Conference
6 8 September, Canberra, Australia
234
Table 4 - Speed Management with Physical Works Star Rating Table
235
This proposed SRIP is estimated to reduce deaths and hospitalisations by 22 annually including
236
approximately eight fatalities on the surveyed network. It would have a benefit of approximately
237
BND$190M over 20 years for a capital expenditure of BND$36M. For this scenario the vehicle
238
occupant star rating of three stars or more increases from 45% to 95% by road length. In addition
239
approximately 25% of the road length would be rated as four or five Stars.
240
Summary and Conclusions
241
The iRAP assessment of Brunei’s strategic road network (in 2014) shows that approximately 45%
242
of strategic roads (and 63% of motorways) have a star rating of three or better for vehicle
243
occupants. The network is performing relatively well compared with other countries in the ASEAN
244
region and many developing countries. However there is plenty that could be done to make the
245
network safer for a relatively low cost (around BND$35M to $50M). Indeed Brunei is well placed
246
to achieve a minimum three star rating on all strategic roads, especially if operating speeds can be
247
reduced.
248
Two safer road improvement programme (SRIP) scenarios were developed to show how the risk of
249
serious injury and fatal crashes could be reduced on Brunei strategic road network. Scenario One
250
includes infrastructure upgrades with a cost of BND$42M. Scenario One, when fully implemented,
251
is expected to reduce the number of fatal and serious crashes per year by 20 (a saving of 7 to 8
252
fatalities), and increase the number of 3 star plus roads to 85%.
253
Scenario Two includes both speed management (reducing operating speeds by typically 5 to
254
10km/h on all highways and main roads) and infrastructure upgrades. The infrastructure upgrades
255
will be around BND$36M. The speed management costs, which will be ongoing, are yet to be
256
priced. Scenario Two, when fully implemented, is expected to reduce the number of fatal and
257
serious crashes per year by 22 (a saving of 8 to 9 fatalities), and increase the number of 3 star plus
258
roads to 95%.
259
Further analysis could be undertaken to determine how this remaining 5% of roads could be
260
upgraded to at least three stars. Such an achievement would make Brunei one of the first countries
261
internationally to achieve this goal of all strategic roads being three stars or better.
262
References
263
Global status report on road safety: time for action. Geneva, World Health Organization, 2009
264
(www.who.int/violence_injury_prevention/road_safety_status/2009).
265
ResearchGate has not been able to resolve any citations for this publication.
ResearchGate has not been able to resolve any references for this publication.