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formula is typically not a factor beyond the balancing of North Carolina's state-maintained highway of division-specific projects. system (80,000 miles), many stakeholders, and North Carolina's FHWA-approved HSIP project cost considerations. programming process requires benefit-cost analysis Most systemwide initiatives are funded with of all safety projects. Projects are selected for pro- TIP money and are not limited to HSIP funding. gramming based on benefit-cost ratios. However, this is a time-consuming (lengthy) and highly competitive process. HSIP Approach: Strengths, Weaknesses, The following improvements to the current and Potential Improvements HSIP approach are being considered: The strengths of the current HSIP approach were NCDOT acknowledges that continued imple- identified as the following: mentation of black spot improvements at cur- The black spot component of the HSIP is rent investment levels probably won't drive refined yearly as additional data, research, the number of fatal crashes down substan- and program evaluation feedback are imple- tially. As a result, there is an effort under way mented. This component is actively managed to investigate ways of transitioning NCDOT's to ensure that at-risk sites are identified as HSIP toward a more systematic deployment well as necessary changes in the work process of strategies. and field staff feedback mechanisms. This NCDOT is considering deployment of new black spot component of the HSIP is also programs to direct safety funds to low-cost flexible. Each year, the black spot program rural intersection improvements, to improve identifies pattern locations that focus on lane bicycle and pedestrian modules, and to further departure (including specific lane departure refine specialized query capabilities to sup- wet and night warrants), intersection locations port safety investigations. (with specific warrants to identify patterns of severe, frontal-impact, night crashes), bridge LESSONS LEARNED locations, and bike/pedestrian crash pattern locations. The program also identifies addi- The states that provided information through the tional focus areas: topics such as larger trucks, survey of practice and the subsequent interviews motorcycles, speed, alcohol, and others can be made it clear that their highway safety programs are added to core focus areas. evolving and that the primary agent of change is the The systematic component of the HSIP is less passage of SAFETEA-LU and the adoption of severe formalized. However, as countermeasures are crashes as the new national safety performance mea- proven to be effective, policies and guidance sure. SAFETEA-LU required the preparation of will be developed that will encourage system- SHSPs, and all of the states had complied by the wide deployment. Examples include the October 2007 deadline. The states indicated that the median barrier program, rumble strips for free- SHSP data-driven development process has helped ways, removal of late night flash from most focus their programs through the identification of signals, and adjustment of clearance intervals their individual Safety Emphasis Areas, which has for all signals. The median crossover limited influenced the type of projects selected for HSIP movement (J-turns) initiative is very success- funding. However, the participating states acknowl- ful and is entrenched in design and operational edged that the adoption of severe crashes as the policies. Safety edge requirements are being safety performance measure has had the most pro- pursued now. found effect on their safety programs. The weaknesses of the current HSIP approach are identified as the following: Finding a Balance--Black Spot versus Systematic Methods The systematic approach is less formal and not as aggressive as the mature black spot pro- The participating states indicated that prior to gram. It can take a long time to implement a SAFETEA-LU their safety programs had been new systemwide initiative due to the large size almost exclusively focused on finding and then 16

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addressing black spots--locations with large num- However, most of the participating states reported bers of crashes--on the their system of highways. that their HSIPs still had a black spot focus. Iowa and However, this process tended to direct safety invest- North Carolina indicated that 50% and 90%, respec- ments toward signalized intersections along high- tively, of their safety funding was directed toward volume, urban, multilane arterials. This historic type locations with high frequencies of crashes. These of safety investment was based on the theory that if states suggested that the reason for this continued crashes were mitigated at locations with high fre- focus on black spots was that the supporting analyti- quencies of crashes, some fatal crashes would be cal process was more mature and better understood by eliminated along with injury and property-damage technical staff. The states also indicated that they crashes. Over time, it became apparent that fatal expected to transition to a more proactive approach as crashes were not decreasing, primarily because new analytical tools and techniques3 become avail- severe crashes are underrepresented in urban areas in able and the number of black spots is reduced. general and particularly at signalized intersections Minnesota has adopted a unique approach in an along high-volume arterials on the state's highway attempt to find a balance between a reactive and system. Mn/DOT's experience provides a good exam- proactive focus for its HSIP by adopting twin goals: ple of this phenomenon. 70% of Metro District safety funding will be directed Mn/DOT has annually published a Top 200 list of to reactively addressing black spots in the Metro Dis- intersections along its 12,000-mile state highway sys- trict (where 70% of Minnesota's Top 200 intersec- tem that is prioritized based on calculated crash cost tions are located) and 70% of rural districts' safety (crash severity adopted cost per crash). These inter- funding will be directed toward the proactive deploy- sections are overwhelmingly signalized (70%) and in ment of low-cost strategies in the rural districts with urban areas (69%). Mn/DOT made it a practice to their large system of rural highways and where only direct some of its HSIP funds every year toward the a few safety investments have been previously imple- highest priority intersections on this list. However, mented (due to the lack of identified black spots). Mn/DOT determined that this approach did not Minnesota provided the following data in support of reduce the number of fatal crashes. The Top 200 its decision to pursue both proactive and reactive intersections accounted for less than 10% of fatal approaches: crashes, and the annual number of fatal intersection- In Minnesota, 70% of all crashes are in urban related crashes remained at approximately 200 per areas, but 70% of fatal crashes are in rural areas. year over the 8-year period between 1998 and 2005. Rural crashes are more severe than urban The national statistics are very clear: well over crashes--the fatality rate on rural roadways one-half of fatal crashes are in rural areas, and approx- in Minnesota is more than 2.5 times the rate in imately one-half of these are on the local system-- urban areas. locations with little or no history of safety investment Fatal crashes in Minnesota are different than because for all practical purposes there are no black less severe crashes. The most common type of spots. The states recognize that the historic approach crash is a rear end (28%)--but the most com- of reacting to black spots cannot be entirely effective mon types of fatal crashes are run off road given the new safety performance measure because (34%), right angle (23%), and head on (17%). most severe crashes are randomly distributed across Rear-end crashes account for only 4% of fatal thousands of miles of rural roads and at tens of thou- crashes. sands of rural intersections, where there is no history of previous severe crashes. As a result, the participat- ing states reported that they are attempting to tran- Addressing All Roads sition their HSIP from a focus on reacting primarily The participating states also indicated that the to black spots in urban areas to a program that provision of SAFETEA-LU that requires the state- includes a rural/urban split that reflects the distri- wide safety program and the underlying crash data bution of severe crashes and a yet-to-be defined bal- ance between a reactive approach of investing at a few black spot locations and a proactive approach that 3 As an example, statistical techniques that account for regres- deploys low-cost improvements widely across the sion to the mean would likely improve the accuracy of estimates rural system of highways. of expected numbers of crashes for a given location. 17

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system to address all public roads has caused them ment of Transportation (IDOT) also provides to re-evaluate their programs and in some cases to safety training to local agencies and dedicates fundamentally alter their approaches to involving approximately 20% of its HSIP funds and all local road authorities. Virtually all of these states of its HRRR funds to safety projects on local indicated that historically their safety programs were systems.5 open to participation by local authorities, and some Iowa (53% of fatal crashes on the local sys- even noted that their data systems were capable of tem) has a mature, map-based, crash records identifying crash locations on the local systems. system (the Crash Mapping Analysis Tool, However, the most common response from the CMAT, available to all local highway agen- states was that they had never allocated safety funds cies, law enforcement, and private engineers) for a project on the local system because the small that covers all roads; individual crashes are number of crashes on the local system made it a spatially located by reference point along all low priority in their evaluation processes. Several roadways in each county in Iowa. The Iowa states reported that subsequent to the passage of DOT also provides training for local engi- SAFETEA-LU and often with the encouragement of neers through an annual safety workshop, and FHWA safety engineers, they revised their safety it directs about 70% of a separate state-funded programs in order to increase the level of involve- safety program to projects developed by local ment with local road authorities (both from the agencies for implementation on local roads. perspective of providing technical assistance and The 70% of the state safety funds directed to directing safety funds toward projects on the local local projects amounts to approximately 18% system). In the states' responses, the importance of all safety expenditures. assigned to increasing the involvement of local road Louisiana (19% of fatal crashes on the local authorities varied. North Carolina assigned a lower system) is implementing the Local Road Safety level of importance to this issue because 80% of its Program (LRSP), which is a partnership roads are in the state system, whereas Iowa and Min- between the Department of Transportation and nesota assigned a high level of importance to this Development and the Local Technical Assis- issue because only 10% of their roads are in the state tance Program (LTAP)/Technology Transfer system. Center. A key component of the LRSP includes The states' responses noted several significant adding two part-time traffic safety engineers achievements including the following: to provide technical assistance to local agencies--crash analysis, safety training, and California (57% of fatal crashes on the local help with the application process for safety system) is in the process of having the Univer- funds. Approximately 25% of the HSIP is sity of California (Berkeley) geo-code all fatal directed toward projects on the local system.6 and severe-injury crashes as well as provide an Michigan (60% of fatal crashes on the local interface with GIS to identify locations with system) created a Local Safety Initiative (LSI) concentrations of crashes. California also ded- in its Department of Transportation and has icates one-half of its HSIP funds to safety proj- dedicated 2.5 engineering full-time equivalents ects on local systems and provides technical to provide technical assistance to local agen- assistance relative to the preparation of appli- cies. LSI provides the RoadSoft Safety Mod- cations for the competitive project selection ule, which includes 10 years of crash data and process.4 output in a GIS format, to local agencies and Illinois (39% of fatal crashes on the local sys- maintains it. The Michigan Department of tem) has added to the state's crash database Transportation (MDOT) has partnered with the the ability to locate all crashes on the local LTAP at Michigan Technical University to system, including output in a GIS format to develop and provide safety training for local identify crash locations. The Illinois Depart- agencies and dedicates about one-third of its 4 T. McDonald and T. Welch. Support by State Departments of 5 Transportation for Local Agency Safety Initiatives. Institute for Ibid. 6 Transportation, Iowa State University, July 2009. Ibid. 18