Integrated Risk Management for Improving Internal Traffic Control, Work-Zone Safety, and Mobility during Major Construction, TPF-5(081), 2012

Highway construction is among the most dangerous industries in the US. Internal traffic control design, along with how construction equipment and vehicles interact with the traveling public, have a significant effect on how safe a highway construction work zone can be. An integrated approach was taken to research work-zone safety issues and mobility, including input from many personnel, ranging from roadway designers to construction laborers and equipment operators. The research team analyzed crash data from Iowa work-zone incident reports and Occupational Safety and Health Administration data for the industry in conjunction with the results of personal interviews, a targeted work-zone ingress and egress survey, and a work-zone pilot project.

Safety and Mobility Impacts of Winter Weather --Phase 3, SPR RB01-012, 2014

Highway agencies spend millions of dollars to ensure safe and efficient winter travel. However, the effectiveness of winter-weather maintenance practices on safety and mobility are somewhat difficult to quantify. Safety and Mobility Impacts of Winter Weather - Phase 1 investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter-weather conditions. In Phase 2, three Iowa Department of Transportation (DOT) high-priority sites were evaluated and realistic maintenance and operations mitigation strategies were also identified. In this project, site prioritization techniques for identifying roadway segments with the potential for safety improvements related to winter-weather crashes, were developed through traditional naïve statistical methods by using raw crash data for seven winter seasons and previously developed metrics. Additionally, crash frequency models were developed using integrated crash data for four winter seasons, with the objective of identifying factors that affect crash frequency during winter seasons and screening roadway segments using the empirical Bayes technique. Based on these prioritization techniques, 11 sites were identified and analyzed in conjunction with input from Iowa DOT district maintenance managers and snowplow operators and the Iowa DOT Road Weather Information System (RWIS) coordinator.

The Recirculator, Vol. 65, No. 1, April 2009.

News for swimming pool and spa operators, mangers, and inspectors.

The Recirculator, Vol. 65, No. 2, September 2009.

News for swimming pool and spa operators, mangers, and inspectors.

The Recirculator, Vol. 65, No. 3, December 2009.

News for swimming pool and spa operators, mangers, and inspectors.

The Recirculator, Vol. 66, No. 1, March 2010.

News for swimming pool and spa operators, mangers, and inspectors.

The Recirculator, Vol. 66, No. 2, October 2010.

News for swimming pool and spa operators, mangers, and inspectors.

The Recirculator, Vol. 64, No. 3, December 2008.

News for swimming pool and spa operators, mangers, and inspectors.

The Recirculator, Vol. 66, No. 3, December 2010.

News for swimming pool and spa operators, mangers, and inspectors.

MEPDG Work Plan Task No. 5: Characterization of Unbound Materials (Soils/Aggregates) for Mechanistic-Empirical Pavement Design Guide, 2009

The resilient modulus (MR) input parameters in the Mechanistic-Empirical Pavement Design Guide (MEPDG) program have a significant effect on the projected pavement performance. The MEPDG program uses three different levels of inputs depending on the desired level of accuracy. The primary objective of this research was to develop a laboratory testing program utilizing the Iowa DOT servo-hydraulic machine system for evaluating typical Iowa unbound materials and to establish a database of input values for MEPDG analysis. This was achieved by carrying out a detailed laboratory testing program designed in accordance with the AASHTO T307 resilient modulus test protocol using common Iowa unbound materials. The program included laboratory tests to characterize basic physical properties of the unbound materials, specimen preparation and repeated load triaxial tests to determine the resilient modulus. The MEPDG resilient modulus input parameter library for Iowa typical unbound pavement materials was established from the repeated load triaxial MR test results. This library includes the non-linear, stress-dependent resilient modulus model coefficients values for level 1 analysis, the unbound material properties values correlated to resilient modulus for level 2 analysis, and the typical resilient modulus values for level 3 analysis. The resilient modulus input parameters library can be utilized when designing low volume roads in the absence of any basic soil testing. Based on the results of this study, the use of level 2 analysis for MEPDG resilient modulus input is recommended since the repeated load triaxial test for level 1 analysis is complicated, time consuming, expensive, and requires sophisticated equipment and skilled operators.

Interlaboratory Study to Determine the Precision of the MIT Scan T2 for PCC Pavement Thickness, MLR 14-01, 2015

The MIT Scan T2 device has been implemented in Iowa as a new method for determining PCC pavement thickness compliance. The T2 device utilizes a magnetic pulse induction technology to measure the distance from a sensor to a metal target. The objective of this project was to conduct an interlaboratory study (ASTM C802) to determine the precision of the test.Fifteen MIT Scan T2 gauges and fifteen operators performed testing on three reference platforms and nine pavement locations of varying thicknesses. The testing was conducted on October 29, 2014 at two sites near Ames, Iowa. Usable data was obtained from every operator at all locations.

Transit Assistance Program for Iowa, 1975

This inventory of transit services in Iowa covers urban transit, intercity passenger bus carriers and charter operators, taxicab operations, rural transit services and special services, and includes the results of questionnaire and interview surveys, and the resulting recommendations. The recommendations urge a centralized source of data and expertise, a public information program, the utilization of federal aid, the continuance of existing transit services with no dimunition of service level, the establishment of new services in communities of over 20,000 population, the sponsorship of demonstrations in communities with populations of 10,000 to 20,000, and the development and improvement of rural transit service. Based on state and local community experience, recommendations are made concerning revenue sources to support transit in Iowa, and four alternative state transit assistance programs are presented.

Synthesis of Best Practice for Increasing Protection and Visibility of Highway Maintenance Vehicles, CTRE Final Report Iowa DOT Project TR-475, August 2002

The purpose of this research project is to study current practices in enhancing visibility and protection of highway maintenance vehicles involved in moving operations such as snow removal and shoulder operations, crack sealing, and pothole patching. The results will enable the maintenance staff to adequately assess the applicability and impact of each strategy to their use and budget. The report’s literature review chapter examines the use of maintenance vehicle warning lights, retroreflective tapes, shadow vehicles and truck-mounted attenuators, and advanced vehicle control systems, as well as other practices to improve visibility for both snowplow operators and vehicles. The chapter concludes that the Manual on Uniform Traffic Control Devices does not specify what color or kind of warning lights to use. Thus, a wide variety of lights are being used on maintenance vehicles. The study of the relevant literatures also suggests that there are no clear guidelines for moving work zones at this time. Two types of surveys were conducted to determine current practices to improve visibility and safety in moving work zones across the country and in the state of Iowa. In the first survey of state departments of transportation, most indicated using amber warning lights on their maintenance vehicles. Almost all the responding states indicated using some form of reflective material on their vehicles to make them more visible. Most participating states indicated that the color of their vehicles is orange. Most states indicated using more warning lights on snow removal vehicles than their other maintenance vehicles. All responding state agencies indicated using shadow vehicles and/or truck-mounted attenuators during their moving operations. In the second survey of Iowa counties, most indicated using very similar traffic control and warning devices during their granular road maintenance and snow removal operations. Mounting warning signs and rotating or strobe lights on the rear of maintenance vehicles is common for Iowa counties. The most common warning devices used during the counties’ snow removal operations are reflective tapes, warning flags, strobe lights, and auxiliary headlamps.

Tree and Brush Control For County Road Right-of-Way, Ocotober 2002

This manual summarizes the roadside tree and brush control methods used by all of Iowa's 99 counties. It is based on interviews conducted in Spring 2002 with county engineers, roadside managers and others. The target audience of this manual is the novice county engineer or roadside manager. Iowa law is nearly silent on roadside tree and brush control, so individual counties have been left to decide on the level of control they want to achieve and maintain. Different solutions have been developed but the goal of every county remains the same: to provide safe roads for the traveling public. Counties in eastern and southern Iowa appear to face the greatest brush control challenge. Most control efforts can be divided into two categories: mechanical and chemical. Mechanical control includes cutting tools and supporting equipment. A chain saw is the most widely used cutting tool. Tractor mounted boom mowers and brush cutters are used to prune miles of brush but have significant safety and aesthetic limitations and boom mowers are easily broken by inexperienced operators. The advent of tree shears and hydraulic thumbs offer unprecedented versatility. Bulldozers are often considered a method of last resort since they reduce large areas to bare ground. Any chipper that violently grabs brush should not be used. Chemical control is the application of herbicide to different parts of a plant: foliar spray is applied to leaves; basal bark spray is applied to the tree trunk; a cut stump treatment is applied to the cambium ring of a cut surface. There is reluctance by many to apply herbicide into the air due to drift concerns. One-third of Iowa counties do not use foliar spray. By contrast, several accepted control methods are directed toward the ground. Freshly cut stumps should be treated to prevent resprouting. Basal bark spray is highly effective in sensitive areas such as near houses. Interest in chemical control is slowly increasing as herbicides and application methods are refined. Fall burning, a third, distinctly separate technique is underused as a brush control method and can be effective if timed correctly. In all, control methods tend to reflect agricultural patterns in a county. The use of chain saws and foliar sprays tends to increase in counties where row crops predominate, and boom mowing tends to increase in counties where grassland predominates. For counties with light to moderate roadside brush, rotational maintenance is the key to effective control. The most comprehensive approach to control is to implement an integrated roadside vegetation management (IRVM) program. An IRVM program is usually directed by a Roadside Manager whose duties may be shared with another position. Funding for control programs comes from the Rural Services Basic portion of a county's budget. The average annual county brush control budget is about $76,000. That figure is thought not to include shared expenses such as fuel and buildings. Start up costs for an IRVM program are less if an existing control program is converted. In addition, IRVM budgets from three different northeastern Iowa counties are offered for comparison in this manual. The manual also includes a chapter on temporary traffic control in rural work zones, a summary of the Iowa Code as it relates to brush control, and rules on avoiding seasonal disturbance of the endangered Indiana bat. Appendices summarize survey and forest cover data, an equipment inventory, sample forms for record keeping, a sample brush control policy, a few legal opinions, a literature search, and a glossary.

Review of Automated Vehicle Technology: Policy and Implementation Implications; Version 1.0; RB28-015, 2016

This report provides recommendations for the state of Iowa over the next five years in regards to automated vehicle policy development. These administrative, planning, legal, and community strategy recommendations for government agencies include: • Encouraging automation by preparing government agencies, infrastructure, leveraging procurement, and advocating for safety mandates • Adjusting long range planning processes by identifying and incorporating a wide range of new automation scenarios • Beginning to analyze and, as necessary, clarify existing law as it apples to automated driving • Auditing existing law • Enforcing existing laws • Ensuring vehicle owners and operators bear the true cost of driving • Embracing flexibility by giving agencies the statutory authority to achieve regulatory goals through different means, allowing them to make small-scale exemptions to statutory regimes and clarifying their enforcement discretion • Thinking locally and preparing publicly • Sharing the steps being taken to promote (as well as to anticipate and regulate) automated driving • Instituting public education about automated vehicle technologies.