THE IMPACT OF SACRAMENTO STATE’S ELECTRONIC BILLBOARD ON TRAFFIC AND SAFETY Mahesh Pandey B.S., Panjab University, India, 1990 PROJECT Submitted in partial satisfaction of the requirements for the degree of MASTER OF SCIENCE in CIVIL ENGINEERING at CALIFORNIA STATE UNIVERSITY, SACRAMENTO SUMMER 2010 THE IMPACT OF SACRAMENTO STATE’S ELECTRONIC BILLBOARD ON TRAFFIC AND SAFETY A Project by Mahesh Pandey Approved by: __________________________________, Committee Chair Kevan Shafizadeh, Ph.D., P.E., PTOE __________________________________, Second Reader Nicholas Compin, Ph.D. ____________________________ Date ii Student: Mahesh Pandey I certify that this student has met the requirements for format contained in the University format manual, and that this project is suitable for shelving in the Library and credit is to be awarded for the Project. __________________________, Graduate Coordinator Cyrus Aryani, Ph.D., P.E., G.E. Department of Civil Engineering iii ________________ Date Abstract of THE IMPACT OF SACRAMENTO STATE’S ELECTRONIC BILLBOARD ON TRAFFIC AND SAFETY by Mahesh Pandey This project is an applied research paper to evaluate the traffic and safety impacts of a new electronic billboard owned by California State University, Sacramento near Highway 50. This project analyzed traffic flow, speed, and lane occupancy for two months before and after the installation of the electronic billboard. Similarly, incident data for one year before and after its installation were compared. All of the required freeway performance data (flow rate, speed, and lane occupancy) including incident data were downloaded from the online California Freeway Performance Measurement System (PeMS) database. A review of previous research was conducted to identify the best methodology for this study. Traffic performance data were analyzed on Wednesdays during morning and afternoon twohour peak periods for two months before and after the installation of the electronic billboard. The crash analysis was completed for a period of one year before and after the installation of the electronic billboard. Public opinion data from an oncampus intercept survey were obtained from the Department of Civil Engineering at Sacramento State. The results indicate that the presence of an electronic billboard does not appear to have a negative impact in traffic performance (flow, speed, and lane occupancy) or incidents on the study section of the freeway based on the data analyzed. More than two-thirds of the individuals surveyed who drive past this billboard regularly believed that the electronic billboard near the campus does not pose a safety risk to traffic. _______________________________, Committee Chair Kevan Shafizadeh, Ph.D., P.E., PTOE _______________________ Date iv ACKNOWLEDGEMENTS I would first like to thank my advisor Dr. Kevan Shafizadeh of the Department of Civil Engineering at California State University, Sacramento (CSUS) for his encouragement, valuable guidance, and support for completing this research project and all my coursework. I am indebted to Dr. Nick Compin of Caltrans for his valuable suggestions and cooperation. I am thankful to Dr. Ramzi Mahmood, the Department chair, and Dr. Cyrus Aryani, the graduate coordinator, for their cooperation with this project as well as all the professors at CSUS who prepared me to reach to this stage. I would like to thank the California Freeway Performance Measurement System (PeMS) for providing necessary data and the CSUS Library for providing necessary information for this project. I thank all my classmates, colleagues at County of Sacramento, and friends for their support and encouragement. I thank my mom and my family members for their support and encouragement. I would like to give my special thanks to my wife Chhaya, daughter Sadikshya, and son Amesh whose patience and love enabled me to complete this work. v TABLE OF CONTENTS Page Acknowledgements .....................................................................................................v Chapter 1. INTRODUCTION ................................................................................................1 2. BACKGROUND ..................................................................................................7 Federal.............................................................................................................8 California and Other States .............................................................................9 The Sacramento State Billboard ...................................................................10 3. LITERATURE REVIEW....................................................................................12 4. DATA .................................................................................................................16 Traffic Data ...................................................................................................16 Errors ...........................................................................................................18 Incident Data .................................................................................................20 Public Opinion ..............................................................................................22 5. METHODOLOGY .............................................................................................23 Traffic Performance ......................................................................................23 Incidents ........................................................................................................26 Public Opinion ..............................................................................................27 6. ANALYSIS AND RESULTS .............................................................................28 Traffic Performance Analysis .......................................................................28 Incident Analysis ..........................................................................................33 Public Opinion ..............................................................................................35 7. CONCLUSIONS AND RECOMMENDATIONS ..............................................38 Limitations ....................................................................................................38 Future Research ............................................................................................39 Appendix A ...............................................................................................................41 Appendix B ...............................................................................................................45 Appendix C ...............................................................................................................47 Appendix D ...............................................................................................................61 References .................................................................................................................76 vi LIST OF TABLES Page 1. Table 1 Eastbound Traffic Measures: Wednesdays Oct to Nov 2007 and 2008 ............ 32 2. Table 2 Westbound Traffic Measures: Wednesdays Oct to Nov 2007 and 2008 ........... 33 3. Table 3 Crash Rate Analysis ........................................................................................... 34 4. Table 4 Eastbound Incident Data- Aug. 2007 to July 2008 ............................................ 61 5. Table 5 Eastbound Incident Data- Aug. 2008 to July 2009 ............................................ 63 6. Table 6 Westbound Incident Data- Aug. 2007 to July 2008 ........................................... 66 7. Table 7 Westbound Incident Data- Aug. 2008 to July 2009 ........................................... 70 vii LIST OF FIGURES Page 1. Figure 1 Sacramento State’s Electronic Billboard ........................................................... 3 2. Figure 2 Vicinity Map...................................................................................................... 5 3. Figure 3 Locations of Known Electronic Billboards ....................................................... 7 4. Figure 4 States and Local Governments Limiting Billboards.......................................... 8 5. Figure 5 Location of Detectors on Highway 50 Study Section ...................................... 18 6. Figure 6 Postmile ............................................................................................................ 21 7. Figure 7 Respondents’ Driving Frequency Through Study Segment ............................. 35 8. Figure 8 Electronic Billboard Recognition by Drivers ................................................... 36 9. Figure 9 Respondents’ Opinion on Distraction .............................................................. 37 10. Figure 10 Respondents’ Opinion on Safety Risk ............................................................ 37 11. Figure 11 October 2007 Eastbound Traffic .................................................................... 47 12. Figure 12 November 2007 Eastbound Traffic ................................................................ 48 13. Figure 13 October 2007 Westbound Traffic ................................................................... 49 14. Figure 14 November 2007 Westbound Traffic ............................................................... 50 15. Figure 15 October 2008 Eastbound Traffic .................................................................... 51 16. Figure 16 November 2008 Eastbound Traffic ................................................................ 52 17. Figure 17 October 2008 Westbound Traffic ................................................................... 53 18. Figure 18 November 2008 Westbound Traffic ............................................................... 54 19. Figure 19 Oct - Nov 2007 Eastbound Relationship Among Basic Parameters............... 55 20. Figure 20 Oct - Nov 2008 Eastbound Relationship Among Basic Parameters............... 56 21. Figure 21 Oct - Nov 2007 Westbound Relationship Among Basic Parameters ............. 57 22. Figure 22 Oct - Nov 2008 Westbound Relationship Among Basic Parameters ............. 58 23. Figure 23 Comparison of Eastbound Traffic (Wednesdays October to November) ....... 59 24. Figure 24 Comparison of Westbound Traffic (Wednesdays October to November) ..... 60 viii 1 Chapter 1 INTRODUCTION Highway 50 is a major highway extending from Interstate 80 (I-80) in West Sacramento through the Sacramento, California metropolitan area to the state of Maryland. Highway 50 near California State University, Sacramento (“Sacramento State”) is an eight-lane freeway with adjacent interchanges at 65th Street and Howe Avenue. A full auxiliary lane exists in each direction between interchanges at 65th Street and at Howe Avenue. Highway 50 serves an important transportation corridor, linking downtown Sacramento with suburban areas to the east. Growth in the corridor is expected to continue, as suburban development occurs in the eastern portions of unincorporated Sacramento County, the City of Rancho Cordova, the City of Folsom, and El Dorado County. The Sacramento Area Council of Governments (SACOG) has identified the City of West Sacramento, Downtown Sacramento, Power Inn/South Watt area, Mather/Rancho Cordova area, Aerojet area, and South Folsom area as locations of high growth (SACOG, 2010). Any disturbances or improvements in traffic conditions on Highway 50 can have a significant impact on the lives of many people in the greater Sacramento area. Any distraction (internal or external to vehicle) is a frequently cited factor in increasing crashes (Farbry, et al., 2001). Mobile phones, music devices, and global positioning system (GPS) devices are some examples of internal factors. The 2 external factors can include other vehicles on the road, construction or other activities on or adjacent to the road, billboards, shop fronts, and even public art installations adjacent to the roadway. Roadside advertising on electronic billboards is one external source designed to attract the attention of drivers and road users. Further, electronic billboards were cited as a cause of driver distraction during a national safety summit hosted by U.S. Transportation Secretary Ray LaHood in Washington, D.C. (Scenic America, 2010). Electronic billboards are becoming a popular means of advertising and providing public information alongside highways. With the application of light emitting diode (LED) technology and computer controls, electronic billboards today can display high quality images and have the capability of updating and displaying new images frequently, typically every six to eight seconds (OAAA, 2009). Electronic billboards on the side of highways have been useful for federal, state, and local law enforcement to display time-sensitive information like traffic conditions, directions/instructions during emergency evacuations, and Amber Alert child abduction bulletins (OAAA, 2009). Law enforcement and other public safety officials can use electronic billboards to reach mass audiences of drivers quickly. This project is an applied research paper to evaluate the traffic and safety impact of a new electronic billboard near Sacramento State adjacent to Highway 50. This project involves an analysis of traffic flow parameters on upstream portions of electronic billboard on both directions of Highway 50 near Sacramento State before and after the installation of the new electronic billboard in August 2008 (as shown in 3 Figure 1). This project analyzed data from the California Freeway Performance Measurement System (PeMS) database for changes in common traffic flow parameters: speed, flow rate, and lane occupancy over a two-month period before and after the installation of the electronic billboard. This project also analyzed crash and collision data from PeMS for changes in non-injury, injury, and fatal crashes (if any) over a one-year period before (August 2007- July 2008) and a one-year period after (August 2008- July 2009) the installation of the electronic billboard. This project will contribute to similar ongoing research studies to help road authorities (e.g., State Departments of Transportation) identify the traffic and safety impacts of the electronic billboards adjacent to freeways. Figure 1: Sacramento State’s Electronic Billboard 4 The 48-foot by 14-foot electronic billboard was constructed at the south end of Sacramento State near Highway 50 (Figure 2) and it has been operating since August 2008. The electronic billboard uses LED technology with the capability of eliminating glare. It also adjusts with the varying light levels of different times of day and weather conditions so that the billboards are not unreasonably bright for the safety of motorists. The display brightness is measured every two to three seconds, and the sign automatically adjusts the brightness to control for ambient light conditions every 30 seconds. This electronic billboard displays up to eight messages every 64 seconds and has provided Sacramento State an opportunity to endorse educational, social, and community programs. Besides the business advertisements, it displays alert messages and emergency and disaster information as needed. In the meantime, this particular electronic billboard was reportedly justified by the removal of six other smaller billboards directly located around the University campus on local city streets (University Enterprises, 2008). 5 N Project location Figure 2: Vicinity Map (Source: Google Maps) Like other electronic billboards, the Sacramento State electronic billboard has embraced real-time capability in reaching people with important public message. Even though the technology has evolved and modern billboards have become innovative and versatile, roadside billboards are primarily designed to attract the attention of drivers and road users. Any kind of distraction has the potential to adversely affect traffic flow and become a factor for increasing crash rates. Therefore, it is important to evaluate any impact of such external elements and their significance on highway operations. Moreover, a campus transportation intercept survey was conducted in May 2010, as a part of an annual evaluation of the campus transportation system. Along with other transportation related questions, the on-campus opinion survey contained 6 questions on distraction and safety due to Sacramento state’s electronic billboard on Highway 50 near 65th Street. Responses to this survey are also included to evaluate the public’s perception of safety towards this electronic billboard adjacent to Highway 50. 7 Chapter 2 BACKGROUND There are approximately 450,000 billboards installed across the United States and about 1,800 of them are electronic billboards (Copeland, 2010). There were approximately 400 electronic billboards in 2007 (Story, 2007). It is a fast-growing sector of the outdoor advertising market. Even though the billboard industry claims that the electronic billboards are not dangerous, not enough research has been done in this field to conclude that they have no impact on the traffic flow and road safety. Most of the states have adopted laws or regulations to allow electronic billboards that display multiple images. Figure 3 is a map indicating the locations of known electronic billboards in the U.S. One can see that there are more of these electronic billboards in the midwest and northeast than in the western U.S. Figure 3: Locations of Known Electronic Billboards (Source: Scenic America, 2010) 8 Some states prohibit all billboards including Alaska, Hawaii, Maine, and Vermont. Similarly, there are some states, where the states and local governments are limiting electronic billboards along public roadways, as shown in Figure 4. Nationwide about 1,500 cities and communities are prohibiting the construction of electronic billboards (Scenic America, 2010). Therefore, it is important to understand the trade-offs between the billboard advertiser’s need to grab driver’s attention and the significance of its impact on the traffic stream and safety. Ban on electronic billboards Moratorium on new billboards Considering moratorium on electronic billboards Figure 4: States and Local Governments Limiting Billboards (Source: USA TODAY, 2010) Federal While the demand for electronic billboards is increasing, electronic and conventional billboards are heavily regulated. The Highway Beautification Act of 1965 and its amendments and regulations of state and local bodies are in place to 9 provide effective control of outdoor advertising. Electronic billboards fall under these regulations. Local laws and ordinances must fulfill these overriding federal and state guidelines. In 2007, the Federal Highway Administration (FHWA) relaxed a rule against electronic billboards. To keep pace with technology, the FHWA has said that roadside billboards could use “changeable message” technologies as long as these signs do not scroll or flash (see Appendix A). The computer-controlled display allows advertisers to change the advertisement slowly at the intervals that prevent driver distraction. The electronic billboards typically switch still advertisement only every four to ten seconds, however eight seconds is recommended (Appendix A). California and Other States A traditional billboard can contain only one advertisement at a time but an electronic billboard can display multiple advertisements in a day. Electronic billboards also allow advertisers to change their message as often as they want because of its computerized operation method. As a result, electronic billboards can generate more income than traditional billboards. Electronic billboards are attracting state and local governments also, in this economic downturn, as a way to generate significant revenue to help reduce the budget deficit. In October 2008, California Department of Transportation (Caltrans) asked the FHWA to allow the conversion of the state’s 692 traffic alert and message signs to state-of-the-art electronic billboards so that they can be leased for business advertisements when not in use for traffic information (Solof, 2009). Governor 10 Arnold Schwarzenegger also proposed an idea of converting overhead freeway changeable message signs (CMSes) into electronic billboards. The Governor sees the plan as a way to generate revenue and improve the technology of warning signs, but critics fear the new signs would distract drivers and lead to more collisions (Yamamura, 2010). If the Governor’s plan is approved, electronic billboards would appear throughout California highways. Massachusetts Bay Transportation Agency (MBTA) is auctioning off space for sixty new electronic billboards along highways in eastern Massachusetts to raise revenue (about $6 million per year) to support the Boston-area bus and train network (Solof, 2009). The MBTA already has more than 200 electronic billboards in place. Some communities and the Massachusetts state legislature are challenging the sign, however many communities and state officials are looking for guidance from the federal government. The Sacramento State Billboard Before the installation of the electronic billboard at Sacramento State, a local neighborhood association, the College-Glen Neighborhood Association (CGNA), opposed the installation of the electronic billboard. In a letter to the Sacramento State administration, a member of the CGNA expressed concerns about the electronic billboard with flashing advertisements; they believed it would create a distraction for drivers and worsen safety on Highway 50 (see Appendix B). In response, Sacramento State, through its auxiliary business arm University 11 Enterprises Incorporated (UEI), assured the CGNA that Caltrans reviewed its request and issued a permit to allow the electronic billboard to be constructed. Further, the University Enterprises clarified that the electronic billboard would not feature animation, flashing lights, or full-motion video. Instead, the advertisement would change image once every eight seconds without glare or light leakage (see Appendix B). The Sacramento State electronic billboard is situated to attract the attention of motorists on Highway 50. This part of the freeway serves as a major access point to Sacramento State, as well as a major corridor for commuters and general road users to downtown Sacramento. While there is some concern that drivers can become distracted, it is essential to determine if there is any negative impact on the performance of traffic or safety due to the presence of this electronic billboard adjacent to the freeway. 12 Chapter 3 LITERATURE REVIEW This literature review focuses on the performance of traffic, safety impacts, and the public perception of electronic billboards on the side of roadways. It is intended to draw guidelines, methodology, and results from previous research to assist in determining the impact of Sacramento State’s electronic billboard on traffic and safety adjacent to Highway 50. There are few studies done in these subject areas. The 1980 FHWA report “Safety and Environmental Design Considerations in the Use of Commercial Electronic Variable Message Signage,” stated that no credible statistical evidence existed to support the conclusion that electronic or variable message signs negatively impacted road safety. However, incident studies reported both positive and negative relationships between accidents, high driving task demand, and the presence of roadside advertisements. The evidence was statistically insufficient to support the relationship between electronic billboards and traffic incidents. The FHWA research report was based on a critical review of reported research, operational experience, and legislative history relating to electronic billboards and outdoor advertising. The research report was intended to provide background information for the development of standards for electronic billboards used for public information and business advertisements adjacent to roadways. The study pointed out various factors to be considered in any 13 development of standards for the design of electronic billboards and suggested more studies be done in this field. The FHWA has performed studies on a regular basis trying to find a relationship between electronic signs and traffic safety. In 2001, the FHWA published another report, “Research Review of Potential Safety Effects of Electronic Billboards on Driver Attention and Distraction,” which reviewed the literature published after the 1980 study. This research project followed the earlier FHWA research in 1980 and reviewed the literature published after the 1980 study. This report found the results to be mixed and inconclusive. However, the report noted that, “studies were identified that verified that: an increase in distraction, a decrease in conspicuity, or a decrease in legibility may cause an increase in the crash rate” (page 8, Farbry, et al., 2001). A research report titled “Traffic Safety Evaluation of Video Advertising Signs” (Smiley et al., 2005) provided information on traffic performance and safety in one section of urban expressway and three intersections. Besides eye fixation and conflicts between driving and external distraction, the researchers studied flow, lane occupancy, headway, speed, crashes, and public opinion to determine the change in traffic parameters before and after electronic billboards were installed. A study conducted by the Center for Automotive Safety Research at Virginia Tech’s Transportation Institute concluded that electronic billboards were “safety neutral,” based on a study of eye glance movements of 36 drivers in speciallyequipped vehicles in Cleveland (Lee, et al., 2007). Participants were told to drive on 14 interstates and surface streets to help understand the way people drive in a natural environment. However, they were not informed about the true purpose of the experiment (Lee, et al., 2007). The study examined driver performance in the presence of electronic billboards, as compared to locations without billboards. They studied drivers’ eye glance behavior towards billboards and digital signs and at control sites without billboards or signs. Speed maintenance and lane-keeping were also recorded. There were no significant differences in speed. The lane-keeping performance was poorer but not significantly different. Because there are not many studies done in this area, a study commissioned by the FHWA recommended further research be done to identify the correlation between electronic billboards and their risk to drivers (Story, 2007). In February 2009, FHWA published another research report, “The Effects of Commercial Electronic Variable Message Signs (CVEMS) on Driver Attention and Distraction: An Update,” which is an update of an earlier work of FHWA, and reviews the research (post-hoc crash studies, field and laboratory investigations, previous literature reviews, and reviews of practice) related to electronic billboards. The research review found the results of previous literature reviews were inconclusive (FHWA, 2009). Based on the literature review, FHWA proposed a long-term program of research, which includes determination of distraction and basis for possible regulation of electronic billboards. The FHWA studies recommended a methodology for gauging driver distraction. It called for an “on-road instrumented vehicle study,” which would identify changes in driving behavior at and around 15 billboard sites with on-board measurement devices in the vehicles of volunteer drivers. 16 Chapter 4 DATA Traffic Data California Freeway Performance Measurement System (PeMS) has been set up to collect real-time data from freeways in the State of California to compute freeway performance measurements and to facilitate other traffic related studies. This system can be accessed through the Internet at http://pems.dot.ca.gov. PeMS collects the raw flow and lane occupancy data that comes from more than 30,000 individual lane detectors every 30 seconds in California (PeMS, 2010). Flow is expressed as the number of vehicles that crosses over a detector during a given time period. It is measured in terms of vehicles per hour (vph) or vehicles per hour per lane (vphpl). Lane occupancy is the percentage of time that a detector is occupied in a given time of period and is a percentage that ranges from 0% to 100%. The lane occupancy is commonly used as a surrogate for the density of the traffic over a road segment. PeMS aggregates the lane-by-lane 30 second data into a single number that represents the five-minute total of vehicle flow over all lanes at that location. The five-minute data sample for flow is computed by summing the individual 30 second data samples. For lane occupancy, the five-minute data sample represents the weighted average over the 30-second data samples received, based on the number of vehicles observed. 17 The majority of loop detectors in the state of California are single loop detectors (Chen, et al., 2001). Speed can be measured directly from radar detectors, but single loop detectors cannot measure speed. PeMS has ability to compute speed for sensors that do not report speed, such as single loop detectors. Double loop detectors are installed in specific spacing, which have the capability of measuring vehicle speed, but PeMS does not use the speed measurements from double loop detectors. PeMS research has shown that their speed calculation algorithm based solely on the flow and lane occupancy are better than speed measured from double loop detectors (PeMS, 2010). Flow, lane occupancy, and speed data were downloaded from the PeMS website then exported into an Excel spreadsheet. The detectors on the study section were identified as sensor # 313684 for eastbound direction and sensor # 312205 for the westbound direction (shown in Figure 5). At these locations, data were obtained in five-minute intervals for the study period (October through November 2007 and October through November 2008) in each direction for all lanes located on the study segment (four lanes on each side). 18 N CSUS Sign Location 312205 Study Segment Figure 5: Location of Detectors on Highway 50 Study Section (Source: PeMS) Errors There are some possible sources of error, which can affect the data obtained from PeMS. These errors may have some effect on the result of the freeway performance analysis. Detector health- The greatest potential for error comes from the detection itself. The data quality depends on the detector health. Detector health involves whether the detector actually measures data and sends it to the controller. The detection problems can occur with failures at the sensors or anywhere in the data transmission process. In absence of real time traffic 19 detector data, PeMS generates the imputed data to fill missing data, which may be different from actual data from the working detector. The imputed data may not be as accurate as data from working sensor. In this study, data reported by detectors were generally 75% - 100%. There were few period when detectors did not report any data, and those data-holes were filled by imputed data. When detectors reported 0% data, the imputed data available in the PeMS database were excluded in the analysis of before and after period traffic measures in this report. Varying traffic type- The traffic volume consists mostly of short passenger cars (average length 16 feet) and long trucks (average length 60 feet). The truck volumes estimated from the PeMS algorithms were not measured. Truck volumes were estimated from five-minute aggregated volume and lane occupancy data. Incidents- Any incident at immediate downstream or upstream of the study segment in the freeway could cause disruptions in the traffic flow, and the data received during this period would affect the analysis. For example, an incident or just downstream of the study segment can cause congestion on the study segment on upstream of traffic flow, which affects the end result. On the other hand, an incident upstream of the study segment causes low flow for certain time followed by a surge in flow after a lane is reopened. 20 Incident Data California Highway Patrol (CHP) has a well-maintained database and a website to record and access incidents on state highways. PeMS has maintained a system to interface with the CHP database and obtain the incident data to store in its database. The incident data contains vehicle incidents information reported by CHP: the time, the location, and the detail of the incident. PeMS also receives incident data from Caltrans Traffic Accident Surveillance and Analysis System (TASAS), which contains data on incidents (but not breakdowns) and the verified locations. PeMS provides the collision data relative to the freeway postmile. California uses a postmile system on all its highways to track highway mileage, which is designated as the absolute postmile in the PeMS database. The absolute postmile is the actual centerline distance along the freeway from the district boundary or the western or southern end of the route. Similarly, the county route postmile starts at the western or southern end of the route or the boundary of the county which contains the highway and is a black marked rectangular white plate marked with a county route number, county designation, and postmile (Figure 6). Mileage is marked nearest to hundredths of a mile and postmiles are used as a reference base for planning, design, maintenance, construction, and operation of the highway system in California (California Highways, 2009). In this study, absolute postmile was considered as a reference distance for analysis purpose along Highway 50 as given in the PeMS database. 21 Figure 6: Postmile (Source: California Highways, 2009) The postmile of the electronic billboard needed to be identified and the crash data was downloaded with respect to the postmile for the study periods from the PeMS database. Current state statutes and regulations employ different values ranging from 500 to 1,000 feet from intersections or interchange for placement of billboards (FHWA, 2001). Based on this distance value, the half-mile (2,640 feet) before the electronic billboard in each direction was considered for evaluation in this study. Sacramento State’s electronic billboard is located near absolute postmile 8.76 (distance from the beginning of the route). Crash data available on the PeMS website for Highway 50 were downloaded from postmile 8.3 to postmile 8.9 in eastbound direction and postmile 8.6 to postmile 9.2 in westbound direction of the posted billboard for the period of one year before (August 2007 to July 2008) and one year after (August 2008 to July 2009) the installation of the electronic billboard. The 22 before and after period incident data for eastbound and westbound direction are given in Appendix D. The incidents on the study segments are shaded in the tables. The postmiles given in the table are absolute distance from western end of Highway 50. Public Opinion Public opinion data was collected as part of an annual Campus Transportation Intercept Survey at Sacramento State. The survey is conducted by students in a transportation engineering course in the Department of Civil Engineering (CE 147). Students in this course randomly stop individuals entering the campus at major access points to ask questions about their trip to campus and their general opinion of transportation services and facilities on campus. Surveys were conducted on May 4 and 6, 2010. There were four questions directly related to the electronic billboard. There were a total 484 respondents of this survey. There were 395 (81.6%) undergraduate students, 37 (7.6%) graduate students, 17 (3.5%) staff, 25 (5.2%) faculty, and 10 (2.1%) others. 23 Chapter 5 METHODOLOGY In the research report “Traffic Safety Evaluation of Video Advertising Signs” (Smiley et al., 2005), the traffic flow, lane occupancy, speed, crash data, and public opinion were similar to the data used in this study. The study by Smiley et al., provided the basic methodology to study the impacts of Sacramento State’s electronic billboard on traffic and safety. Traffic Performance In this study, the safety and traffic performance were analyzed from available traffic data before and after the installation of the electronic billboard near Sacramento State. Speed, flow, and lane occupancy data at the approach of the billboard on Highway 50 in each direction was obtained from the PeMS database. Because all the traffic data were primarily collected through the detectors on the freeway, it was important to identify the location of detectors on the main traffic stream at or nearest to the study segment. Detector locations (detector number) were identified on Highway 50 on eastbound and westbound directions near the billboard. Once the detector numbers were known, the five-minute interval speed, flow, and lane occupancy data were downloaded into Excel from the PeMS database for a period of two months before and after the installation of the sign in the month of 24 October to November 2007 and October to November 2008. The billboard was commissioned on August 2008. There were four lanes in each direction of the study segment. Speed, flow, and lane occupancy were downloaded for each lane. The individual lane data was averaged to compute the mean operating speed, flow per lane, and lane occupancy per lane. PeMS records the hourly flow in five minutes increments. Therefore, the five-minute average flows were converted to hourly flows multiplying by 12. Plots of flow, speed, and lane occupancy were prepared to visualize the traffic performance over the study period in each direction as shown in Figure 11 through Figure 18 in Appendix C. The data recorded on weekends and holidays were removed from the dataset because the traffic operations are not similar on weekdays and weekends. On weekdays, there exists more traffic, which is more sensitive to changes in driver behavior. During the study period, there were four holidays observed. They were Columbus Day, Veterans Day, and Thanksgiving (two days). The data from all individual weekdays were combined into a single, “average weekday,” which contained speed, flow, and lane occupancy in five-minute intervals. Average weekday data were plotted as speed vs. flow, speed vs. lane occupancy and flow vs. lane occupancy to find out any changes in travel pattern before and after the electronic billboard was installed. It was assumed that the low traffic volume and lane occupancy during the off peak periods would be least affected by the electronic billboard. Only peak-hour 25 weekday conditions were analyzed. The study segment was analyzed for any change in performance between 6:30 am to 8:30 am and between 3:30 pm to 5:30 pm. The mean value of speed, flow, and lane occupancy and their standard deviations were computed. Then the speed, flow, and lane occupancy and their standard deviations were compared between the before and after periods to conclude if changes were observed. In this case, the study segment was analyzed for any change in performance during the morning peak period (6:30 am to 8:30 am) and the afternoon peak period (3:30 pm to 5:30 pm) during a typical weekday (Wednesday). Wednesday was chosen arbitrarily, as it was the middle of the week and there were no holidays during the study period. Moreover, traffic studies are generally conducted on Tuesdays, Wednesdays, or Thursdays (Caltrans 2002). The times were chosen to best capture the peak travel period, even though the time of the peak hour can vary from day to day. This peak travel period is most important to a large number of users. Therefore, the mean value of speed, flow, and lane occupancy, and their standard deviations were computed during the morning and afternoon peak periods. Then the speed, flow, and lane occupancy and their standard deviation, were analyzed and compared before and after the electronic billboard was installed to conclude if any changes occurred. For comparison of change in flow, speed, lane occupancy, and their standard deviation, the percent change was calculated using the following equation: 26 Percent Change, % ( Final Initial ) 100 Initial Incidents In the study of the Sacramento State electronic billboard, the post-hoc crash study was considered where incident data was collected for one year prior to, and one year after, operation of the electronic billboard. Vehicle incident data was analyzed to compute the crash rate in each direction during the study period, and the crash rates before and after the installation of the electronic billboard were compared to conclude if changes had occurred. The incident data for the study segment was analyzed and compared to identify if any changes occurred on crashes during the before and after period. Crash rate for collision investigation was calculated based on the number of crashes per MVM (million vehicle miles) by the following equation: Crash Rate per MVM, R a 1,000,000 ADT l d where, a = total number of incidents in one year l = length of segment in miles d = number days (365) during study period, and ADT = average daily traffic. The incident data one year before and one year after the installation of the electronic billboard were downloaded, and crash rates were compared for each direction. The weekend and holidays were also included in the analysis. The study 27 segment was considered 2,640 feet (0.5 miles) to make the evaluation more conservative and inclusive. Analysis was done for a segment of 0.5 miles before the electronic billboard in each direction. To calculate the crash rate, the annual average daily traffic (AADT) and the number of incidents in each direction were obtained from the PeMS database. Public Opinion Public opinion survey data obtained from the Department of Civil Engineering was a part of on-going evaluation of campus transportation system. Only the electronic billboard related responses were included in this report for analysis of opinions of the respondents. The responses were imported into an Excel spreadsheet, and charts were prepared from the responses for quick visualization and analysis purposes. 28 Chapter 6 ANALYSIS AND RESULTS Traffic Performance Analysis The PeMS database provided information for speed, lane occupancy (surrogate for lane density), and flow for every five-minute interval throughout the day. There are 288 intervals per day and 17,856 intervals over the course of two months. To analyze these data, Excel spreadsheets were prepared. The mean and standard deviation were calculated. The data analysis was carried out as outlined below. Flow, speed and lane occupancy against time were plotted to obtain a general overview traffic operation during the study period in the study section as shown in Appendix C (Figure 11 through Figure 18). The plots were real representations of the total data (flow, speed and lane occupancy) obtained from PeMS database in both directions. Moreover, each figure contained plots of flow, speed, and lane occupancy against time, which made it easy to visualize and understand the nonuniformity of traffic on the holidays and on weekends compared to normal weekdays. From the plots, a clear distinction could be made between the weekday and weekend traffic flow patterns. The weekdays had higher peak flow and lane occupancy, and lower speed compared to weekends and/or holidays. From the plots, some data gaps were identified on November 22, 2008 in eastbound traffic (Figure 29 16 in Appendix C). From these figures, the westbound traffic was observed to have more fluctuation in speed compared to eastbound traffic before and after the installation of the electronic billboard. Further, on the same segment the detectors did not report any data after November 22. So, the imputed data available on the PeMS database was excluded from analysis. Greater variation in speed was observed in 2007 for eastbound traffic in November compared to October (Figure 12, and Figure 13 in Appendix C). The five-minute data granularity of the weekdays were averaged to obtain five-minute average values over the 24-hour for the study sections of the study periods. Here the mean values (flow, speed, and lane occupancy) were determined at the increment of five-minutes for a 24-hour period. These data were used to prepare plots of speed vs. lane occupancy, speed vs. flow, and flow vs. lane occupancy in five-minute interval on an average “average weekday” for both directions before and after, as shown in Appendix C (Figure 19, Figure 20, Figure 21, and Figure 22). These plots provided an overview of flow, speed, and lane occupancy with each other. Further, each plot of the basic parameters in each direction before and after the installation of the electronic billboard were observed to be similar. Based on these plots, traffic operation in the study segment before and after the installation of the billboard were not significantly changed in the same direction. However, in westbound direction, for higher flow values, fluctuations in speed were higher than in the eastbound direction. 30 Traffic performances (flow, speed, and lane occupancy) were analyzed for two months before (October - November 2007) and after (October - November 2008) the installation of the electronic billboard. A typical analysis of the Wednesday data was done. The five-minute data points of all Wednesdays were averaged to obtain five-minute average values over the 24-hour period. These fiveminute average values of Wednesday data were used to prepare plots of flow vs. time, speed vs. time, and lane occupancy vs. time for the eastbound direction (Figure 23) and westbound direction (Figure 24), given in Appendix C. These plots provided real time comparison of flow, speed, and lane occupancy in each direction before and after the installation of the electronic billboard during a typical weekday (Wednesday) during the months of October and November. The change in traffic operation parameters (flow, speed, and lane occupancy) before and after the construction of the billboard could be visualized from these plots. The plots provided an idea of the morning and afternoon peak periods and variations of traffic throughout the day. The mean and standard deviation of flow, speed, and lane occupancy over the peak two hours in morning and in afternoon were computed and compared by calculating the change in percentage of the after-period measured to the beforeperiod measure. A decrease in variance of speed may be anticipated to improve safety; however, an increase in mean lane occupancy (i.e. decreased headway) and increased speed variance would likely decrease safety (Smiley, et al., 2005). When drivers get distracted they might slow, resulting in greater speed variability, or might 31 allow unsafe headways or lane occupancy to develop when they fail to react quickly to detect the slowing of the vehicle in front of them. When lower headways develop, there will be less reaction time, and the probability of collision will be higher. Further, a typical analysis of flow, speed, and lane occupancy were done to observe the variation in performance measures during morning and afternoon peak periods in each direction before and after the installation of electronic billboard. In the eastbound direction, the standard deviations (SD) of speed and lane occupancy decreased with the increase in operating mean speed. The increase in speed (25%) during afternoon, and increase in standard deviation (more than 75 %) during morning and afternoon, as shown in Table 1 were unusual and could be the effect of weather (rain), lane closures, or some event in the nearby area particularly on November 2007, as shown in Figure 12. Even though the flow variation during morning was higher after the installation of the electronic billboard, the speed and lane occupancies were not impacted adversely. In the eastbound direction, vehicle speeds, and lane occupancies, through the months of October and November on the Wednesday peak periods after the installation of the electronic billboard, were not found to be impacted (Table 1). 32 Table 1: Eastbound Traffic Measures: Wednesdays Oct to Nov 2007 and 2008 Morning Peak (6:30 - 8:30 AM) Afternoon Peak (3:30 - 5:30 PM ) 2007 2008 % Change 2007 2008 % Change 1,526 1,582 3.72 1,539 1,672 8.62 SD 145 159 9.78 154 119 -22.75 Mean Speed, mph 53.4 62.9 17.76 46.1 57.7 25.09 15.7 1.8 -88.26 19.2 4.5 -76.38 11.82 11.74 -0.63 13.71 13.40 -2.28 2.06 1.33 -35.23 3.37 1.77 -47.47 Mean Flow, vphpl SD Mean Occupancy, % SD Similarly, in the westbound direction vehicle speed, and lane occupancy, through the months of November and December during the Wednesday morning peak period after the installation of the electronic billboard, were found to be better than the year before the installation of the electronic billboard during the same period of time (Table 2). The standard deviations of flow, speed, and lane occupancy decreased with the increase in the operation speed. However, standard deviations of flow, speed, and lane occupancy increased during the afternoon peak period, compared to before period measures. On the other hand, mean speed was higher with the decrease in lane occupancy during the afternoon peak period. The increase in flow variation was observed to have no significant adverse effect on operating speed and lane occupancy. 33 Table 2: Westbound Traffic Measures: Wednesdays Oct to Nov 2007 and 2008 Morning Peak (6:30 - 8:30 AM) Afternoon Peak (3:30 - 5:30 PM ) 2007 2008 % Change 2007 2008 % Change 1,887 1,887 0.00 1,599 1,608 0.56 SD 212 192 -9.44 172 206 19.97 Mean Speed, mph 51.6 54.3 5.29 43.5 46.8 7.67 9.9 9.5 -4.46 16.2 17.2 6.00 17.55 16.17 -7.85 19.47 18.03 -7.40 4.37 3.88 -11.26 7.53 8.11 7.76 Mean Flow, vphpl SD Mean Occupancy, % SD Incident Analysis The average daily traffic (ADT) was computed for both direction during the study period as explained in the methodology for both direction and the duration of study. The crash data downloaded from the PeMS website was sorted to identify the number of incidents on the study segment in each direction during the study period as shown in Appendix D (Table 4, Table 5, Table 6, and Table 7). The crash rates (MVM) for the study segment were calculated using the following equation as explained in the methodology. A sample of crash rate calculation on eastbound direction for August 2007 to July 2008 is given below: Rate per MVM, R a 1,000,000 ADT l d 34 where, a, is the number of collisions in one year = 10 l, is the length of segment = 0.5 mile d, is the number of days during study period = 365 days ADT, is the average daily traffic = 88,424 vehicles (from PeMS data) Sample calculation: R 10 1,000,000 88,424 0.5 365 = 0.62 crashes per MVM The total number of injury and non-injury incidents and the crash rates in one year after the installation of the electronic billboard were found to be lower than in the year before the installation of the electronic billboard in both directions. The results show that the study segment 2,640 feet upstream from the electronic billboard did not exhibit any increase in the crash rate compared to the year before the installation of the electronic billboard in both directions, as seen in Table 3 below. Table 3: Crash Rate Analysis Eastbound Westbound Aug 07 – July 08 Aug 08 – July 09 Aug 07 – July 08 Aug 08 – July 09 AADT 88,424 77,806 94,338 93,543 Number of Incidents 10 7 12 11 Crash Rate (crashes/MVM) 0.62 0.49 0.70 0.64 35 Public Opinion The on-campus survey results showed that a majority (69.2%) of the respondents (333 out of 481) drove through the study segment. Among the survey respondents who drove through the study segment, 24.9% (120) indicated they drove past the electronic billboard daily, while 26.6% (128) indicated they drove past the electronic billboard a few days a week. Another 11.0% (53) and 6.7% (32) indicated that they drove past the electronic billboard weekly or monthly, respectively (Figure 7). A total of 333 respondents indicated that they drove through the study segment at least monthly, among which 85.6% (285) noticed the electronic billboard while driving through the study segment (Figure 8). The result indicates that the driver in the study segment have high awareness of electronic billboard. Figure 7: Respondents’ Driving Frequency Through Study Segment 36 Figure 8: Electronic Billboard Recognition by Drivers Moreover, 285 participants in the survey responded to a question about the potential distraction and safety risk of the electronic billboard. Among these respondents, 34.7% (99) had expressed that the electronic billboard is distracting to drivers (Figure 9), and 31.6 % (90), expressed that the electronic billboard poses a safety risk to traffic (Figure 10). The results indicate that that the majority of the respondents did not have a negative perception towards the electronic billboard regarding distraction and traffic safety. These results also indicate that a large portion of the driving public (one-third) may find this electronic billboard to be a safety concern, even though an analysis of crash data shows a reduction in collision. 37 Figure 9: Respondents’ Opinion on Distraction Figure 10: Respondents’ Opinion on Safety Risk 38 Chapter 7 CONCLUSIONS AND RECOMMENDATIONS The presence of the electronic billboard near Sacramento State does not appear to have a significant negative impact in traffic performance (flow, speed, and lane occupancy) or incidents in the study section of the freeway. Because many of the road users at this segment are probably commuters, they may be familiar with the electronic billboard, and it does not appear to affect their driving. Even though electronic billboards are capable of displaying multiple messages/commercials at different times, the advertisements do not appear to be a major distraction to drivers at this location. No changes in measurable impact on road safety after the installation of the electronic billboard were observed. At the same time, a public opinion survey indicated that more than two-thirds of self-identified drivers through the study area who were surveyed believed that this electronic billboard does not pose a safety risk to traffic. Limitations It is recognized that this study has many limitations. The period was of two months before and after the installation of electronic billboard considered in the study of traffic performance (flow, speed, and lane occupancy). Analysis of longer periods of time before and after the installation of the electronic billboard could yield more reliable results. At the same time, this study primarily focused on 39 morning and afternoon peak periods on Wednesdays. A broader study could include more electronic billboards and the analysis of traffic on more days and more times. Also, drivers involved in an incident may not want to say whether the incident occurred as a result of the electronic billboard. As a result, positively identifying driver distraction because of the electronic billboard can be difficult. The PeMS database only provides information based on injury or non-injury incidents. The data from the campus opinion survey was limited to a two-day random sample of the campus population, which may be a different demographic group (gender, age, employment status, and income) of travelers on the study segment on Highway 50. Including a more representative sample of the segment population may provide more results relevant to the users of this freeway. Overall, based on this narrowly-scoped project, we cannot make generalizations or conclusions about the safety of all electronic billboards next to highways. Different locations may have different roadway characteristics and different travel patterns, and drivers may react differently in other locations. Future Research There are few other factors affecting the traffic performance on the study segments. The impact of gasoline prices, economic downturn, weather, and ban on cell-phone use during driving may have some effect on traffic performance and on traffic safety. Similarly, the number or density of electronic billboards in a particular section, the types of advertisement, the types of road users (gender, age, employment 40 status, and income), and the travel patterns in different location are other factors to consider for study. Because these factors also affect traffic performance and safety, it would be useful to take these factors into account when determining their relative importance to the presence of an electronic billboard. Altogether, the results would be able to more definitively identify if there is an impact of electronic billboard on traffic performance and safety. Further, the similar studies in different locations would be helpful to better generalize the safety impacts of electronic billboards on state highways. 41 APPENDIX A FHWA Guidance on Off-Premise Message Sign (Source: OAAA, 2009) 42 43 44 45 APPENDIX B 46 47 APPENDIX C Figure 11: October 2007 Eastbound Traffic 48 Figure 12: November 2007 Eastbound Traffic 49 Figure 13: October 2007 Westbound Traffic 50 Figure 14: November 2007 Westbound Traffic 51 Figure 15: October 2008 Eastbound Traffic 52 Figure 16: November 2008 Eastbound Traffic 53 Figure 17: October 2008 Westbound Traffic 54 Figure 18: November 2008 Westbound Traffic 55 Figure 19: Oct - Nov 2007 Eastbound Relationship Among Basic Parameters 56 Figure 20: Oct - Nov 2008 Eastbound Relationship Among Basic Parameters 57 Figure 21: Oct - Nov 2007 Westbound Relationship Among Basic Parameters 58 Figure 22: Oct - Nov 2008 Westbound Relationship Among Basic Parameters 59 Figure 23: Comparison of Eastbound Traffic (Wednesdays October to November) 60 Figure 24: Comparison of Westbound Traffic (Wednesdays October to November) 61 APPENDIX D Table 4: Eastbound Incident Data- Aug. 2007 to July 2008 (Source: PeMS) # 343 Start 8/22/2007 7:48 Duration (mins) 18 Abs Postmile 8.1 Location EB US50 AT 65TH ST Description 1182 - Collision Non Injury 1316 10/31/2007 17:02 0 8.1 65TH ST AT EB US50 1182 - Collision Non Injury 1963 11/1/2007 23:49 2 8.1 65TH ST AT EB US50 20002 - Hit & Run No Injuries 817 12/31/2007 14:01 47 8.1 65TH ST AT EB US50 20002 - Hit & Run No Injuries 953 1/17/2008 15:36 3 8.1 EB US50 ON 65TH ST OFR 1183H - Collision Blocking Lane - No Details 1554 1/17/2008 20:50 0 8.1 EB US50 ON 65TH ST OFR 1183H - Collision Blocking Lane - No Details 1691 2/14/2008 22:06 59 8.1 EB US50 AT 65TH ST 1182 - Collision Non Injury 608 3/5/2008 11:49 35 8.1 65TH ST ONR TO EB US50 1183 - Collision - No Further Details 624 7/14/2008 10:34 6 8.1 65TH ST ONR TO EB US50 1183 - Collision - No Further Details 534 7/19/2008 9:24 10 8.1 65TH ST ONR TO EB US50 1179 - Collision Ambulance Responding 1196 8/17/2007 15:23 31 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 309 9/18/2007 7:59 21 8.3 EB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 276 1/31/2008 7:41 2 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 62 2/9/2008 20:35 34 8.3 EB US50 JEO 65TH ST 1183 - Collision - No Further Details 2/11/2008 8:14 81 8.3 EB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1883 3/1/2008 22:47 1 8.3 EB US50 JEO 65TH ST 1179H - Collision Ambulance Blocking Lane 1524 4/18/2008 18:02 6 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 1900 5/26/2008 22:25 28 8.3 EB US50 JEO 65TH ST 1183 - Collision - No Further Details 624 5/29/2008 11:50 26 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 7/2/2008 21:59 0 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 9/15/2007 6:05 51 8.83 EB US50 JWO HOWE AV 1183 - Collision - No Further Details 10/18/2007 17:30 1 8.83 EB US50 JWO HOWE AV 1183 - Collision - No Further Details 2/11/2008 8:15 0 8.83 EB US50 JWO HOWE AV 1183H - Collision Blocking Lane - No Details 1592 335 1911 336 1170 337 63 Table 5: Eastbound Incident Data- Aug. 2008 to July 2009 (Source: PeMS) # 948 Start 8/16/2008 13:42 Duration (mins) 1 Abs Postmile 8.1 Location EB US50 AT 65TH ST Description 1182 - Collision Non Injury 9/5/2008 20:02 13 8.1 EB US50 AT 65TH ST 1182 - Collision Non Injury 887 10/17/2008 14:23 5 8.1 EB US50 AT 65TH ST 1183 - Collision - No Further Details 186 11/8/2008 2:15 11 8.1 EB US50 AT 65TH ST 1183 - Collision - No Further Details 1295 11/20/2008 17:42 39 8.1 EB US50 AT 65TH ST 1182H - Collision Non Injury - Blocking Lane 405 11/26/2008 10:07 34 8.1 EB US50 AT 65TH ST 1183 - Collision - No Further Details 300 11/27/2008 8:31 1 8.1 EB US50 AT 65TH ST 20002 - Hit & Run No Injuries 241 12/12/2008 6:47 148 8.1 EB US50 AT 65TH ST 1182 - Collision Non Injury 394 12/21/2008 7:55 70 8.1 EB US50 AT 65TH ST 1182H - Collision Non Injury - Blocking Lane 700 12/27/2008 12:29 1 8.1 EB US50 AT 65TH ST 1183H - Collision Blocking Lane - No Details 526 1/6/2009 11:15 0 8.1 65TH ST AT EB US50 1183 - Collision - No Further Details 1557 1/7/2009 21:19 2 8.1 65TH ST JSO EB US50 20002 - Hit & Run No Injuries 1209 2/6/2009 15:14 0 8.1 EB US50 AT 65TH ST 1182H - Collision Non Injury - Blocking Lane 2/18/2009 8:20 20 8.1 65TH ST ONR TO EB US50 20002 - Hit & Run No Injuries 1791 399 64 911 3/11/2009 13:22 1 8.1 EB US50 ON 65TH ST OFR 1182 - Collision Non Injury 1669 3/13/2009 18:11 54 8.1 EB US50 AT 65TH ST 1182 - Collision Non Injury 343 3/23/2009 7:53 34 8.1 EB US50 AT 65TH ST 1179 - Collision Ambulance Responding 986 3/28/2009 13:00 102 8.1 EB US50 AT 65TH ST 1179 - Collision Ambulance Responding 1971 4/7/2009 21:28 19 8.1 65TH ST ONR TO EB US50 1179 - Collision Ambulance Responding 961 5/2/2009 13:13 17 8.1 EB US50 AT 65TH ST 1183H - Collision Blocking Lane - No Details 747 5/10/2009 11:03 13 8.1 EB US50 AT 65TH ST 1179H - Collision Ambulance Blocking Lane 1527 5/22/2009 16:13 51 8.1 EB US50 AT 65TH ST 1182 - Collision Non Injury 1423 6/8/2009 16:34 74 8.1 EB US50 AT 65TH ST 1179H - Collision Ambulance Blocking Lane 2228 6/14/2009 22:31 27 8.1 EB US50 ON 65TH ST OFR 1183H - Collision Blocking Lane - No Details 1619 6/23/2009 17:40 0 8.1 EB US50 AT 65TH ST 20002 - Hit & Run No Injuries 1379 7/10/2009 15:43 5 8.1 EB US50 ON 65TH ST OFR 1182 - Collision Non Injury 9/3/2008 8:32 1 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 1358 10/15/2008 17:54 0 8.3 EB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1157 10/18/2008 16:22 3 8.3 EB US50 JEO 65TH ST 20002 - Hit & Run No Injuries 3/3/2009 9:58 0 8.3 EB US50 JEO 65TH ST 1182 - Collision Non Injury 3/10/2009 16:54 13 8.3 EB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 389 559 1384 65 1579 6/23/2009 17:25 4 8.3 EB US50 JEO 65TH ST 1183 - Collision - No Further Details 2008 7/17/2009 18:47 0 8.3 EB US50 JEO 65TH ST 1183 - Collision - No Further Details 1659 8/2/2008 19:29 0 8.83 EB US50 JWO HOWE AV 1179 - Collision Ambulance Responding 9/9/2008 8:51 2 8.83 EB US50 JWO HOWE AV 1182 - Collision Non Injury 10/15/2008 17:54 0 8.83 EB US50 JWO HOWE AV 1183 - Collision - No Further Details 3/3/2009 9:57 1 8.83 EB US50 JWO HOWE AV 1182 - Collision Non Injury 1179 4/16/2009 15:05 5 8.83 EB US50 JWO HOWE AV 1183H - Collision Blocking Lane - No Details 1572 6/23/2009 17:23 12 8.83 EB US50 JWO HOWE AV 1182H - Collision Non Injury - Blocking Lane 7/4/2009 9:13 24 8.83 EB US50 JWO HOWE AV 1183 - Collision - No Further Details 405 1356 555 657 66 Table 6: Westbound Incident Data- Aug. 2007 to July 2008 (Source: PeMS) # Duration (mins) 0 754 Start 7/27/2008 12:54 987 7/25/2008 14:40 0 1331 7/22/2008 18:07 Abs Postmile 8.66 Location WB US50 JEO 65TH ST Description 1183H - Collision Blocking Lane - 8.66 WB US50 JWO STATE COLLEGE 1182 - Collision Non Injury 33 8.66 WB US50 JEO 65TH ST 1179H - Collision Ambulance Blocking Lane 7/1/2008 8:04 1 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 1731 6/11/2008 19:44 1 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 1120 5/2/2008 15:34 1 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 354 4/30/2008 8:39 13 8.66 WB US50 JWO STATE COLLEGE 1182H - Collision Non Injury Blocking Lane 152 4/21/2008 5:16 46 8.66 WB US50 JEO 65TH ST 1179H - Collision Ambulance Blocking Lane 1428 4/9/2008 18:11 0 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 1230 4/8/2008 17:41 7 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1016 3/27/2008 16:09 0 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 1012 3/27/2008 16:08 55 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 279 3/20/2008 7:25 13 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 355 67 3/4/2008 8:09 1 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 2/15/2008 16:09 1 8.66 WB US50 JEO 65TH ST 20002 - Hit & Run - No Injuries 2/8/2008 11:48 1 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 7/10/2008 0:58 4 8.86 WB US50 JWO HOWE AV 1183H - Collision Blocking Lane - No Details 1324 2/7/2008 17:46 10 8.86 WB US50 JWO HOWE AV 1179 - Collision Ambulance Responding 1053 1/3/2008 15:31 4 8.86 WB US50 JWO HOWE AV 1182 - Collision Non Injury 1278 12/3/2007 16:50 34 8.86 WB US50 JWO HOWE AV 1183 - Collision No Further Details 1353 11/28/2007 18:27 5 8.86 WB US50 JWO HOWE AV 1183 - Collision No Further Details 898 11/10/2007 13:22 4 8.86 WB US50 JWO HOWE AV 1183H - Collision Blocking Lane - No Details 1348 10/23/2007 18:11 49 8.86 WB US50 JWO HOWE AV 1183H - Collision Blocking Lane - No Details 522 10/16/2007 10:28 0 8.86 WB US50 JWO HOWE AV 1183 - Collision No Further Details 450 8/16/2007 8:40 82 8.86 WB US50 JWO HOWE AV 1183 - Collision No Further Details 1093 5/19/2008 15:13 3 9.06 WB US50 AT HOWE AV 1182 - Collision Non Injury 5/9/2008 11:20 9 9.06 HOWE AV ONR TO WB US50 1183 - Collision No Further Details 1257 4/29/2008 16:45 115 9.06 WB US50 AT HOWE AV 1182 - Collision Non Injury 597 3/14/2008 12:19 49 9.06 WB US50 ON HOWE AV OFR 20002 - Hit & Run - No Injuries 269 1/28/2008 7:09 5 9.06 WB US50 ON HOWE AV OFR 1182H - Collision Non Injury Blocking Lane 289 1212 636 88 622 68 12/23/2007 12:23 11 9.06 WB US50 ON HOWE AV OFR 1182H - Collision Non Injury Blocking Lane 12/3/2007 17:13 0 9.06 HOWE AV ONR TO WB US50 1183 - Collision No Further Details 512 10/30/2007 10:09 0 9.06 HOWE AV ONR TO WB US50 1179 - Collision Ambulance Responding 509 10/30/2007 10:07 137 9.06 WB US50 ON HOWE AV OFR 1179 - Collision Ambulance Responding 1245 10/2/2007 17:19 0 9.06 HOWE AV ONR TO WB US50 1179 - Collision Ambulance Responding 1244 10/2/2007 17:18 2 9.06 HOWE AV ONR TO WB US50 1179H - Collision Ambulance Blocking Lane 1448 9/24/2007 17:47 28 9.06 WB US50 AT HOWE AV 1183H - Collision Blocking Lane - No Details 335 9/24/2007 7:37 21 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 1377 9/21/2007 17:01 16 9.06 WB US50 ON HOWE AV OFR 1183 - Collision No Further Details 1103 9/17/2007 15:39 30 9.06 WB US50 ON HOWE AV OFR 1179H - Collision Ambulance Blocking Lane 9/7/2007 10:09 4 9.06 HOWE AV ONR TO WB US50 1183 - Collision No Further Details 35 8/5/2007 0:16 57 9.26 WB US50 JEO HOWE AV 1179 - Collision Ambulance Responding 93 8/23/2007 1:33 4 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 1257 8/23/2007 15:56 99 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 1285 8/23/2007 16:09 28 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 215 10/9/2007 6:40 1 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 10/18/2007 17:52 3 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 801 1331 532 1226 69 1338 10/25/2007 17:48 18 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 2032 12/6/2007 21:57 9 9.26 WB US50 JEO HOWE AV 1183H - Collision Blocking Lane - No Details 1498 12/7/2007 17:30 8 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 1454 1/22/2008 18:08 1 9.26 WB US50 JEO HOWE AV 1182 - Collision Non Injury 1854 3/12/2008 23:14 1 9.26 WB US50 JEO HOWE AV 1179 - Collision Ambulance Responding 1553 3/15/2008 18:58 42 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 494 4/18/2008 9:43 288 9.26 WB US50 JEO HOWE AV 1179H - Collision Ambulance Blocking Lane 1434 5/21/2008 16:53 19 9.26 WB US50 JEO HOWE AV 1182 - Collision Non Injury 674 5/31/2008 11:39 16 9.26 WB US50 JEO HOWE AV 1179 - Collision Ambulance Responding 333 6/7/2008 5:29 28 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 348 7/18/2008 7:32 21 9.26 WB US50 JEO HOWE AV 20002 - Hit & Run - No Injuries 743 7/27/2008 12:47 33 9.26 WB US50 JEO HOWE AV 1179 - Collision Ambulance Responding 70 Table 7: Westbound Incident Data- Aug. 2008 to July 2009 (Source: PeMS) # 606 Start 8/19/2008 12:33 Duration (mins) 15 Abs Postmile 8.66 Location WB US50 JEO 65TH ST Description 1182 - Collision Non Injury 1117 8/22/2008 15:32 0 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 1074 9/4/2008 15:38 0 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 989 9/10/2008 15:42 2 8.66 WB US50 JEO 65TH ST 20002 - Hit & Run - No Injuries 1431 9/24/2008 17:45 13 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 1205 10/17/2008 16:33 0 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 1218 10/17/2008 16:38 7 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 364 10/21/2008 9:01 7 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 1413 10/23/2008 17:45 11 8.66 WB US50 JEO 65TH ST 1179 - Collision Ambulance Responding 1377 11/5/2008 17:55 0 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1056 11/10/2008 15:56 41 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 1168 11/21/2008 16:12 12 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1394 11/26/2008 18:04 0 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1016 12/5/2008 15:29 2 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 71 1256 12/6/2008 17:18 34 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 1522 12/22/2008 17:40 0 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 924 12/29/2008 14:21 60 8.66 WB US50 JEO 65TH ST 1179 - Collision Ambulance Responding 1771 1/1/2009 19:05 47 8.66 WB US50 JEO 65TH ST 20002 - Hit & Run - No Injuries 1443 1/14/2009 17:19 51 8.66 WB US50 JEO 65TH ST 1179H - Collision Ambulance Blocking Lane 1616 1/29/2009 18:30 32 8.66 WB US50 JEO 65TH ST 1182H - Collision Non Injury Blocking Lane 815 2/24/2009 12:31 0 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 449 3/1/2009 7:27 23 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 254 3/11/2009 7:07 50 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1543 4/7/2009 18:08 32 8.66 WB US50 JWO STATE COLLEGE 1183H - Collision Blocking Lane - No Details 1709 4/7/2009 19:16 20 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1388 4/23/2009 16:12 40 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 5/6/2009 9:46 27 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 6/4/2009 16:43 0 8.66 WB US50 JEO 65TH ST 20002 - Hit & Run - No Injuries 823 6/17/2009 13:13 20 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 1190 6/18/2009 15:15 53 8.66 WB US50 JEO 65TH ST 20002 - Hit & Run - No Injuries 7/1/2009 5:59 14 8.66 WB US50 JEO 65TH ST 1179H - Collision Ambulance Blocking Lane 564 1497 261 72 528 7/7/2009 9:48 17 8.66 WB US50 JEO 65TH ST 1182 - Collision Non Injury 536 7/10/2009 9:44 35 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 505 7/21/2009 8:59 2 8.66 WB US50 JEO 65TH ST 1183 - Collision No Further Details 1421 7/30/2009 16:26 42 8.66 WB US50 JEO 65TH ST 1183H - Collision Blocking Lane - No Details 1070 9/4/2008 15:37 50 8.86 WB US50 JWO HOWE AV 1183 - Collision No Further Details 1370 10/23/2008 17:28 14 8.86 WB US50 JWO HOWE AV 1182 - Collision Non Injury 1126 10/26/2008 17:07 123 8.86 WB US50 JWO HOWE AV 1179 - Collision Ambulance Responding 1665 1/30/2009 18:01 1 8.86 WB US50 JWO HOWE AV 1182 - Collision Non Injury 1453 3/3/2009 16:22 90 8.86 WB US50 JWO HOWE AV 1183H - Collision Blocking Lane - No Details 1374 3/10/2009 16:53 0 8.86 WB US50 JWO HOWE AV 1182 - Collision Non Injury 1253 4/24/2009 15:14 1 8.86 WB US50 JWO HOWE AV 1182 - Collision Non Injury 1301 9/28/2008 16:54 0 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 1358 10/7/2008 17:32 0 9.06 WB US50 AT HOWE AV 1182 - Collision Non Injury 1277 10/23/2008 16:46 32 9.06 HOWE AV ONR TO WB US50 20002 - Hit & Run - No Injuries 343 11/20/2008 8:46 19 9.06 HOWE AV ONR TO WB US50 1183 - Collision No Further Details 1006 11/26/2008 15:19 18 9.06 WB US50 ON HOWE AV OFR 1182H - Collision Non Injury Blocking Lane 12/5/2008 15:03 50 9.06 HOWE AV ONR TO WB US50 1182 - Collision Non Injury 957 73 998 12/9/2008 16:03 119 9.06 WB US50 ON HOWE AV OFR 1183H - Collision Blocking Lane - No Details 909 12/21/2008 14:18 33 9.06 WB US50 AT HOWE AV 1182H - Collision Non Injury Blocking Lane 931 12/29/2008 14:23 0 9.06 WB US50 AT HOWE AV 1183 - Collision No Further Details 1/2/2009 18:00 33 9.06 HOWE AV ONR TO WB US50 1182H - Collision Non Injury Blocking Lane 1/4/2009 1:49 28 9.06 HOWE AV ONR TO WB US50 1179 - Collision Ambulance Responding 1510 1/14/2009 17:45 59 9.06 WB US50 ON HOWE AV OFR 1182H - Collision Non Injury Blocking Lane 1193 1/19/2009 15:29 14 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 2/9/2009 7:25 42 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 1344 2/13/2009 14:57 29 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 841 2/15/2009 12:43 9 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 1521 2/22/2009 18:07 17 9.06 HOWE AV ONR TO WB US50 1183 - Collision No Further Details 1483 2/25/2009 16:39 8 9.06 WB US50 AT HOWE AV 1183 - Collision No Further Details 1174 4/7/2009 15:47 23 9.06 HOWE AV JNO WB US50 20002 - Hit & Run - No Injuries 1672 6/4/2009 17:49 38 9.06 WB US50 ON HOWE AV OFR 1182H - Collision Non Injury Blocking Lane 319 6/17/2009 7:34 24 9.06 WB US50 ON HOWE AV OFR 1182 - Collision Non Injury 1367 9/3/2008 17:24 20 9.26 WB US50 JEO HOWE AV 1179H - Collision Ambulance Blocking Lane 1217 9/11/2008 17:03 2 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 1414 147 307 74 9/26/2008 17:27 2 9.26 WB US50 JEO HOWE AV 20002 - Hit & Run - No Injuries 10/16/2008 8:01 24 9.26 WB US50 JEO HOWE AV 1182 - Collision Non Injury 1283 11/1/2008 16:25 36 9.26 WB US50 JEO HOWE AV 1182 - Collision Non Injury 527 11/4/2008 10:15 3 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 647 11/26/2008 12:44 34 9.26 WB US50 JEO HOWE AV 1183H - Collision Blocking Lane - No Details 322 12/15/2008 7:38 16 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 1207 12/16/2008 16:50 34 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 1816 1/23/2009 18:30 0 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 1451 1/27/2009 17:47 30 9.26 WB US50 JEO HOWE AV 1182 - Collision Non Injury 1258 2/2/2009 15:25 10 9.26 WB US50 JEO HOWE AV 1183 - Collision No Further Details 361 2/3/2009 8:31 54 9.26 WB US50 JEO HOWE AV 20002 - Hit & Run - No Injuries 765 2/21/2009 11:40 61 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 583 2/25/2009 10:10 14 9.26 WB US50 JEO HOWE AV 1179H - Collision Ambulance Blocking Lane 1406 3/3/2009 16:09 3 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 1422 3/3/2009 16:13 146 9.26 WB US50 JEO HOWE AV 1182H - Collision Non Injury Blocking Lane 1432 3/3/2009 16:16 14 9.26 WB US50 JEO HOWE AV 1182 - Collision Non Injury 1749 3/3/2009 18:20 53 9.26 WB US50 JEO HOWE AV 1179 - Collision Ambulance Responding 1435 275 75 4/28/2009 7:04 0 9.26 WB US50 JEO HOWE AV 20002 - Hit & Run - No Injuries 4/30/2009 16:26 43 9.26 WB US50 JEO HOWE AV 1182H - 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