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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 VI-5

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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 VI-6

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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) VI-7

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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. VI-8