Best Practices for Low-Cost Safety Improvements on Iowa’s Local Roads, 2008

Many good maintenance practices are done routinely to ensure safe travel on low-volume local roads. In addition, there are many specific treatments that may go beyond the point of routine maintenance and in fact provide additional safety benefits with a relatively low price tag. The purpose of this publication is to try to assemble many of these treatments that are currently practiced in Iowa by local agencies into one, easy-to-reference handbook that not only provides some clarity to each treatment with photos and narrative, but also features references to agencies currently using that technique. Some strategies that are utilized by Iowa, other states, and are topics of research have also been included to allow the user more information about possible options. Even though some areas overlap, the strategies presented have been grouped together in the following areas: Signing and Delineation, Traffic "Calming," Pavement Marking and Rumble Strips/Stripes, Roadside and Clear Zone, Guardrail and Barriers, Lighting, Pavements and Shoulders, Intersections, Railroad Crossings, Bridges and Culverts, and Miscellaneous. The intention is to make this a “living” document, which will continue to be updated and expanded periodically as other existing practices are recognized or new practices come into being.

Traffic Safety Analysis for Local Agencies, 2012

Although many larger Iowa cities have staff traffic engineers who have a dedicated interest in safety, smaller jurisdictions do not. Rural agencies and small communities must rely on consultants, if available, or local staff to identify locations with a high number of crashes and to devise mitigating measures. However, smaller agencies in Iowa have other available options to receive assistance in obtaining and interpreting crash data. These options are addressed in this manual. Many proposed road improvements or alternatives can be evaluated using methods that do not require in-depth engineering analysis. The Iowa Department of Transportation (DOT) supported developing this manual to provide a tool that assists communities and rural agencies in identifying and analyzing local roadway-related traffic safety concerns. In the past, a limited number of traffic safety professionals had access to adequate tools and training to evaluate potential safety problems quickly and efficiently and select possible solutions. Present-day programs and information are much more conducive to the widespread dissemination of crash data, mapping, data comparison, and alternative selections and comparisons. Information is available and in formats that do not require specialized training to understand and use. This manual describes several methods for reviewing crash data at a given location, identifying possible contributing causes, selecting countermeasures, and conducting economic analyses for the proposed mitigation. The Federal Highway Administration (FHWA) has also developed other analysis tools, which are described in the manual. This manual can also serve as a reference for traffic engineers and other analysts.

Improving Traffic Safety Culture in Iowa, 2011

Vehicle crashes rank among the leading causes of death in the United States. In 2006, the AAA Foundation for Traffic Safety “made a long- term commitment to address the safety culture of the United States, as it relates to traffic safety, by launching a sustained research and educational outreach initiative.” An initiative to produce a culture of safety in Iowa includes the Iowa Comprehensive Highway Safety Plan (CHSP). The Iowa CHSP “engages diverse safety stakeholders and charts the course for the state, bringing to bear sound science and the power of shared community values to change the culture and achieve a standard of safer travel for our citizens.” Despite the state’s ongoing efforts toward highway safety, an average of 445 deaths and thousands of injuries occur on Iowa’s public roads each year. As such, a need exists to revisit the concept of safety culture from a diverse, multi-disciplinary perspective in an effort to improve traffic safety. This study summarizes the best practices and effective laws in improving safety culture in the United States and abroad. Additionally, this study solicited the opinions of experts in public health, education, law enforcement, public policy, social psychology, safety advocacy, and traffic safety engineering in a bid to assess the traffic safety culture initiatives in Iowa. Recommendations for improving traffic safety culture are offered in line with the top five Iowa CHSP safety policy strategies, which are young drivers, occupant protection, motorcycle safety, traffic safety enforcement and traffic safety improvement program, as well as the eight safety program strategies outlined in the CHSP. As a result of this study, eleven high-level goals were developed, each with specific actions to support its success. The goals are: improve emergency medical services response, toughen law enforcement and prosecution, increase safety belt use, reduce speeding-related crashes, reduce alcohol-related crashes, improve commercial vehicle safety, improve motorcycle safety, improve young driver education, improve older driver safety, strengthen teenage licensing process, and reduce distracted driving.

Improving Safety for Slow Moving Vehicles on Iowa's High-Speed Rural Roadways, TR-572, 2009

Among the variety of road users and vehicle types that travel on U.S. public roadways, slow moving vehicles (SMVs) present unique safety and operations issues. SMVs include vehicles that do not maintain a constant speed of 25 mph, such as large farm equipment, construction vehicles, or horse-drawn buggies. Though the number of crashes involving SMVs is relatively small, SMV crashes tend to be severe. Additionally, SMVs can be encountered regularly on non-Interstate/non-expressway public roadways, but motorists may not be accustomed to these vehicles. This project was designed to improve transportation safety for SMVs on Iowa’s public roadway system. This report includes a literature review that shows various SMV statistics and laws across the United States, a crash study based on three years of Iowa SMV crash data, and recommendations from the SMV community.

Field Testing of Abrasive Delivery Systems in Winter Maintenance, TR-458, 2009

The key goals in winter maintenance operations are preserving the safety and mobility of the traveling public. To do this, it is in general necessary to try to increase the friction of the road surface above the typical friction levels found on a snow or ice covered roadway. Because of prior work on the performance of abrasives (discussed in greater detail in chapter 2) a key concern when using abrasives has become how to ensure the greatest increase in pavement friction when using abrasives for the longest period of time. There are a number of ways in which the usage of abrasives can be optimized, and these methods are discussed and compared in this report. In addition, results of an Iowa DOT test of zero-velocity spreaders are presented. Additionally in this study the results of field studies conducted in Johnson County Iowa on the road surface friction of pavements treated with abrasive applications using different modes of delivery are presented. The experiments were not able to determine any significant difference in material placement performance between a standard delivery system and a chute based delivery system. The report makes a number of recommendations based upon the reviews and the experiments.

Report on the Iowa Department of Public Safety for the year ended June 30, 2014

Report on the Iowa Department of Public Safety for the year ended June 30, 2014

Iowa Department of Public Safety Annual Report, FY2014

The Iowa Department of Public Safety (DPS) has a history of dedication and service to the citizens of Iowa and those who visit our state. Since it was first established in 1939, DPS has been the chief law enforcement agency in the State of Iowa. DPS is headquartered in Des Moines, Iowa in the Wallace State Office Building on the Capitol Complex, along with a statewide presence.

Synthesis Study: Effectiveness of Safety Corridor Programs, Report on Tasks 1-3, 2008

This report synthesizes the safety corridor programs of 13 states that currently have some type of program: Alaska, California, Florida, Kentucky, Minnesota, New Jersey, New Mexico, New York, Ohio, Oregon, Pennsylvania, Virginia, and Washington. This synthesis can help Midwestern states implement their own safety corridor programs and select pilot corridors or enhance existing corridors. Survey and interview information about the states’ programs was gathered from members of each state department of transportation (DOT) and Federal Highway Administration (FHWA) division office. Topics discussed included definitions of a safety corridor; length and number of corridors in the program; criteria for selection of a corridor; measures of effectiveness of an implemented safety corridor; organizational structure of the program; funding and legislation issues; and engineering, education, enforcement, and emergency medical service strategies. Safety corridor programs with successful results were then examined in more detail, and field visits were made to Kansas, Oregon, Pennsylvania, and Washington for first-hand observations. With the survey and field visit information, several characteristics of successful safety corridor programs were identified, including multidisciplinary (3E and 4E) efforts; selection, evaluation, and decommissioning strategies; organization structure, champions, and funding; task forces and Corridor Safety Action Plans; road safety audits; and legislation and other safety issues. Based on the synthesis, the report makes recommendations for establishing and maintaining a successful safety corridor program.

Remote Sensing (LIDAR) for Management of Highway Assets for Safety, 2003

The main objective of this study was to utilize light detection and ranging (LIDAR) technology to obtain highway safety-related information. The safety needs of older drivers in terms of prolonged reaction times were taken into consideration. The tasks undertaken in this study were (1) identification of crashes that older drivers are more likely to be involved in, (2) identification of highway geometric features that are important in such crashes, (3) utilization of LIDAR data for obtaining information on the identified highway geometric features, and (4) assessment of the feasibility of using LIDAR data for such applications. A review of previous research indicated that older drivers have difficulty negotiating intersections, and it was recognized that intersection sight triangles were critical to safe intersection negotiation. LIDAR data were utilized to obtain information on potential sight distance obstructions at six selected intersections located on the Iowa Highway 1 corridor by conducting in-office line-of-sight analysis. Crash frequency, older driver involvement, and data availability were considerations in the selection of the six intersections. Results of the in-office analysis were then validated by visiting the intersections in the field. Sixty-six potential sight distance obstructions were identified by the line-of-sight analysis, out of which 62 (89.8%) were confirmed while four (5.8%) were not confirmed by the video. At least three (4.4%) potential sight distance obstructions were discovered in the video that were not detected by the line-of-sight analysis. The intersection with the highest crash frequency involving older drivers was correctly found to have obstructions located within the intersection sight triangles. Based on research results, it is concluded that LIDAR data can be utilized for identifying potential sight distance obstructions at intersections. The safety of older drivers can be enhanced by locating and rectifying intersections with obstructions in sight triangles.

Safety Benefits of Paved Shoulders, 2009

Single vehicle run-off-road (ROR) crashes are the largest type of fatal passenger vehicle crash in the United States (NCHRP 500 2003). In Iowa, ROR crashes accounted for 36% of rural crashes and 9% of total crashes in 2006. Run-off-road crashes accounted for more than 61.8% of rural fatal crashes and 32.6% of total fatal crashes in Iowa in 2006. Paved shoulders are a potential countermeasure for ROR crashes. Several studies are available which have generally indicated that paved shoulders are effective in reducing crashes. However, the number of studies that quantify the benefits are limited. The research described in this report evaluates the effectiveness of paved shoulders. Model results indicated that covariate for speed limit was not significant at the 0.05 confidence level and was removed from the model. All other variables which resulted in the final model were significant at the 0.05 confidence level. The final model indicated that season of the year was significant in indicating expected number of total monthly crashes with a higher number of crashes occurring in the winter and fall than for spring and summer. The model also indicated that presence of rumble strips, paved shoulder width, unpaved shoulder width, and presence of a divided median were correlated with a decrease in crashes. The model also indicated that roadway sections with paved shoulders had fewer crashes in the after period as compared to both the before period and control sections. The actual impact of paved shoulders depends on several other covariates as indicated in the final model such as installation year and width of paved shoulders. However, comparing the expected number of total crashes before and after installation of paved shoulders for several scenarios indicated around a 4.6% reduction in the expected number of monthly crashes in the after period.

Road Safety Audit for US 52 in Dubuque County from IA 136 to the NCL of Dubuque, 2008

A section of US 52 between Dubuque and Luxemburg, Iowa, was listed in the top 5% of Iowa highways for severe crashes involving impaired drivers and single vehicle run-off-road crashes during 2001–2005, and several crashes have occurred on this roadway near the towns of Luxemburg, Holy Cross, and Rickardsville, Iowa, many on curves. Staff and officials from the Iowa Department of Transportation (Iowa DOT), Iowa State Patrol, Governor’s Traffic Safety Bureau, Federal Highway Administration, Center for Transportation Research and Education Dubuque County, and a retired fire chief met to review crash data and discuss potential safety improvements to U.S. Highway 52. This report outlines the findings and recommendations of the road safety audit team to address the safety concerns on this US 52 corridor and explains several mitigation strategies that the Iowa DOT District 6 Office has selected.

Road Safety Audit for Union County IA 25 from the WCL of Creston to North H-24 Intersection, 2008

In April 2008 a preliminary investigation of fatal and major injury crashes on Iowa’s primary road system from 2001 through 2007 was conducted by the Iowa Department of Transportation, Office of Traffic and Safety. A mapping of these data revealed an apparent concentration of these serious crashes on a section of Iowa 25 north of Creston. Based on this information, a road safety audit of this roadway section was requested by the Office of Traffic and Safety. Iowa 25 is a two-lane asphaltic concrete pavement roadway, 22 ft in width with approximately 6 ft wide granular shoulders. Originally constructed in 1939, the roadway was last rehabilitated in 1996 with a 4-in. asphalt overlay. Except for shoulder paving through a curve area, no additional work beyond routine maintenance has been accomplished in the section. The 2004 traffic map indicates that IA 25 has a traffic volume of approximately 2070 vehicles per day with 160 commercial vehicles. The posted speed is 55 mph. This report contains a discussion of audit team findings, crash and roadway data, and recommendations for possible mitigation of safety concerns for this roadway section.

Road Safety Audit for US 6 from the ECL of Iowa City to the WCL of West Liberty in Johnson and Muscatine Counties, Iowa, 2008

Approximately 13.2 miles of US 6 in eastern Iowa extends from the east corporate limits of Iowa City, Iowa, to the west corporate limits of West Liberty, Iowa. This segment of US 6 is a service level B primary highway, with an annual daily traffic volume varying from 3,480 vehicles per day (vpd) to 5,700 vpd. According to 2001–2007 crash density data from the Iowa Department of Transportation (Iowa DOT), the corridor is currently listed among the top 5% of non-freeway Iowa DOT roads in several crash categories, including crashes involving excessive speed, impaired drivers, single-vehicle run-off-road, and multiple-vehicle crossed centerline. A road safety audit of this corridor was deemed appropriate by the Iowa Department of Transportation’s Office of Traffic and Safety. Staff and officials from the Iowa DOT, Iowa State Patrol, Governor’s Traffic Safety Bureau, Federal Highway Administration, Center for Transportation Research and Education, and several local law enforcement and transportation agencies met to review crash data and discuss potential safety improvements to this segment of US 6. This report outlines the findings and recommendations of the road safety audit team to address the safety concerns on this US 6 corridor and explains several selected mitigation strategies.

Road Safety Audit Report for US 61 from the ECL of Muscatine to the WCL of, 2008

U.S. Highway 61 between Muscatine and Davenport, Iowa, is a four-lane divided section of road approximately 21 miles in length. This section was found to be among the top 5% of Iowa roadways for single-vehicle run-off-road, impaired driver, unbelted driver, and speed-related crashes for the period of 2001 through 2005. A road safety audit of this corridor was deemed appropriate by the Iowa Department of Transportation’s Office of Traffic and Safety. Staff and officials from the Iowa Department of Transportation (Iowa DOT), Iowa State Patrol, Governor’s Traffic Safety Bureau, Federal Highway Administration, Center for Transportation Research and Education, and several local law enforcement and transportation agencies met to review crash data and discuss potential safety improvements to US 61. This report outlines the findings and recommendations of the road safety audit team to address the safety concerns on this US 61 corridor and explains several selected mitigation strategies.