160｜Practice

Practical application of a public involvementtype system for planning and evaluating roadtraffic safety measures
1. Background and goals
In 1997, the year this project started, about 10,000 people each year died in road traffic accidents inJapan. After the beginning of the twenty-first century, this number significantly decreased, but there arestill an excessive number of road traffic accident-related fatalities. Even though fatality rates have been
cut in half, the present need for further reduction remains unchanged.
Developing increasingly sophisticated road traffic safety measures for further reduction of traffic
accidents will require not only governmental policies, but public involvement as well. This project aims
at constructing public involvement-based road traffic safety policies and evaluation systems, using theseas tools to conduct pilot surveys, and verifying their effects.

2. Research content
This project consists of four pillars, based on which
local governments can reduce road traffic accidents
by half over the medium term:
1. Objective data assessment of road traffic accidents and “hiyarihatto experiences”(1)2. Information exchange among citizens, andbetween citizens and local governments
3. Training and utilization of experts
4. Quantitative evaluation of the effects of roadtraffic safety measures
To put this into practice, we developed a roadtraffic accident reduction system for local governments that utilizes Web-based GIS and the Internet,

Understanding
accident
circumstances

Citizen road users
Postevaluation

Information
disclosure

Needs

Information
provision
Government

Measureimplementation

Supportsystems
Data
Information
gathering collection

Determining
accident factors

Specializedknowledge
Academicsand experts

Planningmeasures

Figure 1. Road traffic accident reduction system
for local governments

and applied this system to the city of Kamagaya,
Chiba Prefecture, as a case model. The system is composed of four subsystems, allowing for implemen-

Project Leader: Hirokazu Akahane
Professor, Department of Architecture and Civil Engineering, Faculty of Engineering, Chiba Institute of Technology(1) “Hiyarihatto experiences”: Named after a Japanese term referring to a close call, hiyarihatto experiences are subjective reports by road
users who experience feelings of fright and danger on roads.

Practical application of a public involvement-type system for planning and evaluating road traffic safety measures｜161

tation of road traffic safety measures according to the PDCA cycle.(2)(1) Road traffic safety measure support subsystem

Utilizing a road traffic accident database as its core, this system allows foradvanced GIS (3) -based aggregation,
searching, and spatial analysis of accident data. Using the hiyarihatto map
creation system, which will be
described in the following section, theroad traffic safety measure support system is capable of integrating accident
data with hiyarihatto experience reports
from road users and district residents.

Hiyarihatto
experience
database

GIS
Map display ofhiyarihatto experience data
Locations with many

Integrated
reported accidents andmanagement of hiyarihatto experience reports
both data types

Map database
Road traffic
accident
database

Map display of road traffic
accident data
Types of accidents at specific locations

Figure 2. GIS integration of data regarding accidents and hiyarihatto
experiences

The system thus allows extraction of locations with road traffic safety problems, making it possible
to organize information in various ways, such as by type of accident and by conditions under which
accidents occur.
(2) Road traffic safety information web-based subsystem

This subsystem is composed of ahiyarihatto map creation system
and a road traffic safety information website. The hiyarihatto map
creation system allows road users
and area residents to participate
via reporting their hiyarihatto
experiences using a website managed by local governments, whichuses this information to generate

Web-accessible
database server• Accident data input• Accident analysis andproposed measures

Internet[Measure support system]
Synchronous server

Traffic engineer

LAN[Hiyarihatto experience reporting system]
Database

Citizens• Hiyarihatto experience
reports• Viewing accident andmeasures informationa hiyarihatto map. The road traffic
Figure 3. Road traffic safety information web-based subsystemsafety information website has
information related to traffic safety policies managed by local governments, and such collection of information from road users and area residents along with information presentation and dissemination by(2) PDCA cycle: A method of continual operational process management performed by repeatedly Planning, Doing, Checking, and Acting.
(3) GIS: Geographic information system. This refers to technologies for comprehensively managing and processing data with associatedpositioning information (spatial data) and presenting that data visually, allowing for advanced analysis and rapid decision making(Source: http://www.gsi.go.jp/GIS/whatisgis.html).

162｜Practice

local governments enables the sharing of traffic safety information between local governments andcitizens.
(3) Road traffic safety measures examination subsystem

This subsystem uses investigation and analysis of locations
extracted from the road traffic
safety measures support subs y s t e m a s c a n d i d at e s f orinstalling measures, allowing
for scientific identification ofaccident factors and subsequent prioritization of safetymeasures. This mechanism
employs not only traditional
forms of public involvement,such as questionnaires andWorkshop

Analysis and consideration content
Extract locations with manymarked spots and factors
causing accidents(1) Road traffic accidents(2) Questionnaire on
hiyarihatto experiences(3) Traffic volume
investigation(4) Road conditions• Local residents(10 residents’associations)• Elementary and juniorhigh schools (2)(Faculty and PTA)

Provision of expertiseConsideration of safety measures’content

Awareness of issues, evaluation• Clubs for the elderly (1)• City Hall

Experimental implementationof speed humps and roadnarrowers (Pilot survey)• Academics and experts(Kamagaya PoliceDepartment)

Propose comprehensive safety measures(Plan for device deployment)(Consideration of traffic regulation)

4

Figure 4. Framework of road traffic safety system measures in the Higashi-

briefings, but also workshops
hatsutomi district
and pilot surveys that allow
citizens to be directly involved in the examination and implementation of measures.
(4) Road traffic safety measures implementation evaluation subsystem

based on the subsystem’s evaluations. Two forms of evaluation

tion before and after measure
implementation, according to
the aforementioned road traffic
safety measure support andEvaluation index

Evaluation index value• Influx of throughtraffic into the district• Vehicle speed is toofast• Location speed• Number of vehicles
passing through• Road users• Awareness of residents
in the area of devices• Ratio of vehicles travelingat 30 km/h or faster• Difference in volume ofthrough traffic• Safety improvements• Measures evaluation

Surveyimplementation

Effects analysis

Measure proposal andimplementation• Installation of speed
humps at intersections• Colored paving atintersections(Objective) (Subjective)

can be performed: objective
evaluations based on quantitative comparison of the situa-

Accident factors(Objective) (Subjective)

This subsystem evaluates theeffects of implemented traffic
safety measures and provides
feedback, allowing further
improvements to b e made• Location speed survey• License tag survey• Probe investigation• Questionnaire survey• Web-based survey• 26% decrease in the ratioof vehicles traveling at
30 km/h or faster• Through traffic reducedby 14%• 56% recognized speed
decrease• 75% approved of measures

Feedback
Figure 5. Measure effect evaluation subsystem (speed reduction measures)

road traffic safety information
web-based subsystem, and subjective evaluations based on collecting and sorting road user and area resident opinions regarding roadPractical application of a public involvement-type system for planning and evaluating road traffic safety measures｜163

traffic safety measures, according to theroad traffic safety information website.

Speed control measures in the Higashi-hatsutomi district

From 2001 to 2002 in Kamagaya, we initiated a pilot survey and evaluated theeffects regarding measures for intersections with high accident rates, and verified
an approximate 60% reduction in trafficaccidents. Encouraged by these results, inSpeed humps at intersections

2004 we performed a pilot survey on comprehensive safety measures regarding
through-traffic on residential roads in
Kamagaya’s Higashi-hatsutomi 4-chome

Specificmeasures
対策内容
Speedhumps at intersections[10 locations]
交差点ハンプ【10 箇所】
Coloredpaving at intersections
locations]
交差点カラー舗装【5[5箇所】

district, which covers an area of approxiFigure 6. Installing speed humps, etc. at intersections
mately 64 ha containing 1,800 households.
(Higashi-hatsutomi district)
Based on information sharing and consensus building at a workshop hosted by local government representatives, the local city hall, and experts,
the district implemented measures such as installing speed humps at ten intersections, resulting in an
approximately 56% accident reduction. Furthermore, the number of reported sudden hiyarihatto experiences and locations fell by 77% and 65%, respectively. Based on these experiences and results in Kamagaya, we created and verified our workflow and developed a training program for users.

3. Conclusions
We have transferred the system from Kamagaya to the neighboring cities of Ichikawa and Shirai, whichhave approximately four times and one half the population of Kamagaya, respectively, with the goal ofclarifying challenges to system construction and operation. This has helped verify the versatility andeffectiveness of the “Kamagaya Scheme.” We have also realized multilingualization of the system throughthe use of Internet-based translation services such as application service providers, and have begun
operation of the system in Penang, Malaysia.

4. Future outlook
Dissemination and continuation of the “Kamagaya Scheme” will require (1) the hosting of seminars foragencies responsible for traffic safety policy implementation, (2) implementing workshops related tosafety technologies and administrative practices for road traffic safety engineers, (3) supporting implementation and operation of the scheme, and (4) supplementing the various databases used in the schemeand promoting sharing between local governments. We believe that doing this will make our system anincreasingly useful tool for countries to collaboratively share experiences and accumulate data relating
to road traffic safety measures.