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SECTION VI--GUIDANCE FOR IMPLEMENTATION OF THE AASHTO STRATEGIC HIGHWAY SAFETY PLAN
Implementation Step 1: Identify and Define the Problem
General Description
Program development begins with gathering data and creating and analyzing information.
The implementation process being described in this guide is one that will be done in the
context of a larger strategic process. It is expected that this guide will be used when the
strategic process, or a project-level analysis, has identified a potentially significant problem
in this emphasis area.
Data analyses done at the strategic level normally are done with a limited amount of detail.
They are usually the top layer in a "drill-down" process. Therefore, while those previous
analyses should be reviewed and used as appropriate, it will often be the case that further
studies are needed to completely define the issues.
It is also often the case that a core technical working group will have been formed by
the lead agency to direct and carry out the process. This group can conduct the analyses
required in this step, but should seek, as soon as possible, to involve any other stakeholders
who may desire to provide input to this process. Step 2 deals further with the organization
of the working group.
The objectives of this first step are as follows:
1. Confirm that a problem exists in this emphasis area.
2. Detail the characteristics of the problem to allow identification of likely approaches
for eliminating or reducing it.
3. Confirm with management, given the new information, that the planning and
implementation process should proceed.
The objectives will entail locating the best available data and analyzing them to highlight
either geographic concentrations of the problem or over-representation of the problem
within the population being studied.
Identification of existing problems is a responsive approach. This can be complemented by a
proactive approach that seeks to identify potentially hazardous conditions or populations.
For the responsive type of analyses, one generally begins with basic crash records that are
maintained by agencies within the jurisdiction. This is usually combined, where feasible,
with other safety data maintained by one or more agencies. The other data could include
· Roadway inventory,
· Driver records (enforcement, licensing, courts), or
· Emergency medical service and trauma center data.
To have the desired level of impact on highway safety, it is important to consider the
highway system as a whole. Where multiple jurisdictions are responsible for various parts
of the system, they should all be included in the analysis, wherever possible. The best
example of this is a state plan for highway safety that includes consideration of the extensive
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SECTION VI--GUIDANCE FOR IMPLEMENTATION OF THE AASHTO STRATEGIC HIGHWAY SAFETY PLAN
mileage administered by local agencies. To accomplish problem identification in this manner
will require a cooperative, coordinated process. For further discussion on the problem
identification process, see Appendix D and the further references contained therein.
In some cases, very limited data are available for a portion of the roads in the jurisdiction.
This can occur for a local road maintained by a state or with a local agency that has very
limited resources for maintaining major databases. Lack of data is a serious limitation to this
process, but must be dealt with. It may be that for a specific study, special data collection
efforts can be included as part of the project funding. While crash records may be maintained
for most of the roads in the system, the level of detail, such as good location information,
may be quite limited. It is useful to draw upon local knowledge to supplement data,
including
· Local law enforcement,
· State district and maintenance engineers,
· Local engineering staff, and
· Local residents and road users.
These sources of information may provide useful insights for identifying hazardous
locations. In addition, local transportation agencies may be able to provide supplementary
data from their archives. Finally, some of the proactive approaches mentioned below may be
used where good records are not available.
Maximum effectiveness often calls for going beyond data in the files to include special
supplemental data collected on crashes, behavioral data, site inventories, and citizen input.
Analyses should reflect the use of statistical methods that are currently recognized as valid
within the profession.
Proactive elements could include
· Changes to policies, design guides, design criteria, and specifications based upon
research and experience;
· Retrofitting existing sites or highway elements to conform to updated criteria (perhaps
with an appropriate priority scheme);
· Taking advantage of lessons learned from previous projects;
· Road safety audits, including on-site visits;
· Safety management based on roadway inventories;
· Input from police officers and road users; and
· Input from experts through such programs as the NHTSA traffic records assessment
team.
The result of this step is normally a report that includes tables and graphs that clearly
demonstrate the types of problems and detail some of their key characteristics. Such reports
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SECTION VI--GUIDANCE FOR IMPLEMENTATION OF THE AASHTO STRATEGIC HIGHWAY SAFETY PLAN
should be presented in a manner to allow top management to quickly grasp the key findings
and help them decide which of the emphasis areas should be pursued further, and at what
level of funding. However, the report must also document the detailed work that has been
done, so that those who do the later stages of work will have the necessary background.
Specific Elements
1. Define the scope of the analysis
1.1. All crashes in the entire jurisdiction
1.2. A subset of crash types (whose characteristics suggest they are treatable, using
strategies from the emphasis area)
1.3. A portion of the jurisdiction
1.4. A portion of the population (whose attributes suggest they are treatable using
strategies from the emphasis area)
2. Define safety measures to be used for responsive analyses
2.1. Crash measures
2.1.1. Frequency (all crashes or by crash type)
2.1.2. Measures of exposure
2.1.3. Decide on role of frequency versus rates
2.2. Behavioral measures
2.2.1. Conflicts
2.2.2. Erratic maneuvers
2.2.3. Illegal maneuvers
2.2.4. Aggressive actions
2.2.5. Speed
2.3. Other measures
2.3.1. Citizen complaints
2.3.2. Marks or damage on roadway and appurtenances, as well as crash
debris
3. Define measures for proactive analyses
3.1. Comparison with updated and changed policies, design guides, design
criteria, and specifications
3.2. Conditions related to lessons learned from previous projects
3.3. Hazard indices or risk analyses calculated using data from roadway
inventories to input to risk-based models
3.4. Input from police officers and road users
4. Collect data
4.1. Data on record (e.g., crash records, roadway inventory, medical data, driver-
licensing data, citations, other)
4.2. Field data (e.g., supplementary crash and inventory data, behavioral
observations, operational data)
4.3. Use of road safety audits, or adaptations
5. Analyze data
5.1. Data plots (charts, tables, and maps) to identify possible patterns, and
concentrations (See Appendixes Y, Z and AA for examples of what some
states are doing)
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SECTION VI--GUIDANCE FOR IMPLEMENTATION OF THE AASHTO STRATEGIC HIGHWAY SAFETY PLAN
5.2.Statistical analysis (high-hazard locations, over-representation of contributing
circumstances, crash types, conditions, and populations)
5.3. Use expertise, through road safety audits or program assessment teams
5.4. Focus upon key attributes for which action is feasible:
5.4.1. Factors potentially contributing to the problems
5.4.2. Specific populations contributing to, and affected by, the problems
5.4.3. Those parts of the system contributing to a large portion of the
problem
6. Report results and receive approval to pursue solutions to identified problems (approvals
being sought here are primarily a confirmation of the need to proceed and likely levels of resources
required)
6.1. Sort problems by type
6.1.1. Portion of the total problem
6.1.2. Vehicle, highway/environment, enforcement, education, other
driver actions, emergency medical system, legislation, and system
management
6.1.3. According to applicable funding programs
6.1.4. According to political jurisdictions
6.2. Preliminary listing of the types of strategies that might be applicable
6.3. Order-of-magnitude estimates of time and cost to prepare implementation
plan
6.4. Listing of agencies that should be involved, and their potential roles
(including an outline of the organizational framework intended for the
working group). Go to Step 2 for more on this.
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