Engineering Study Automating Iowa's Speed Monitoring Program, HR-228, 1983

Excessive speed on State and County highways is recognized as a serious problem by many Iowans. Speed increases both the risk and severity of accidents. Studies conducted by the FHWA and NHTSA have concluded that if average speeds were increased by five MPH, fatalities would increase by at least 2,200 annually. Along with the safety problems associated with excessive speed are important energy considerations. When the national speed limit was lowered to 55 MPH in 1974, a tremendous savings in fuel was realized. The estimated actual savings for automobiles amounted to 2.2 billion gallons, an average of 20.75 gallons for each of the 106 million automobiles registered in 1975. These benefits prompted the Federal-Aid Amendment of 1974 requiring annual State enforcement certification as a prerequisite for approval of Federal-aid highway projects. In 1978, the United States D.O.T. recommended to Congress significant changes in speed limit legislation designed to increase compliance with the national speed limit. The Highway Safety Act of 1978 provides for both withholding Federal-aid highway funds and awarding incentive grants based on speed compliance data submitted annually. The objective of this study was to develop and make operational, an automatic speed monitoring system which would have flexible capabilities of collecting accurate speed data on all road systems in Iowa. It was concluded that the Automatic Speed Monitoring Program in Iowa has been successful and needed data is being collected in the most economical manner possible.

Solar Powered Highway Delineator System, HR-367, 1993

Currently, many drivers experience some difficulty in viewing the road ahead of them during times of reduced visibility, such as rain, snow, fog, or the darkness of night- Recent studies done by the National Safety Council provide a detailed contrast between fatal accidents occurring during the day and night. Revealed was that the motor vehicle night death rate (4.41 deaths per 100 million miles driven) was sharply higher than the corresponding death rate during daylight hours (1.21). By providing a delineating system powered by the natural resource of solar power, a constant source of visibility may be maintained throughout the evening. Along with providing enough light to trace the outline of the road, other major goals defined in producing this delineator system are as follows: 1. A strong and durable design that would protect the internal components and survive extreme weather conditions. 2. A low maintenance system where components need few repairs or replacements. 3. A design which makes all components accessible in the event that maintenance is needed, but also prevents vandalism. 4. A design that provides greater visibility to drivers and will not harm a vehicle or its passengers in the event of a collision. This solar powered highway delineator consists of an adjustable solar array, a light fixture, and a standard delineator pole. The solar array houses and protects the solar panels, and can be easily adjusted to obtain a maximum amount of sunlight. The light fixture primarily houses the battery, the circuit and the light assembly. Both components allow for easy accessibility and reduce vandalism using internal connections for bolts and wires. The delineator mounting pole is designed to extensively deform in the event of a collision, therefore reducing any harm caused to the vehicle and/or the passengers. The cost of a single prototype to be produced is approximately $70.00 excluding labor costs. However, these material and labor costs will be greatly reduced if a large number of delineators are produced. It is recommended that the Iowa Department of Transportation take full advantage of the research and development put into this delineator design. The principles used in creating this delineator can be used to provide an outline for drivers to follow, or on a larger scale, provide actual roadway lighting in areas where it was never before possible or economically feasible. In either event, the number of fatal accidents will be decreased due to the improved driver visibility in the evening.

Development and Implementation of an Expert System for Forecasting Fog on US Highway 30 in Cedar Rapids, Iowa, HR-357, 1996

Several accidents, some involving fatalities, have occurred on U.S. Highway 30 near the Archer Daniels Midland Company (ADM) Corn Sweeteners plant in Cedar Rapids, Iowa. A contributing factor to many of these accidents has been the large amounts of water (vapor and liquid) emitted from multiple sources at ADM's facility located along the south side of the highway. Weather and road closure data acquired from IDOT have been used to develop a database of meteorological conditions preceding and accompanying closure of Highway 30 in Cedar Rapids. An expert system and a FORTRAN program were developed as aids in decision making with regard to closure of Highway 30 near the plant. The computer programs were used for testing, evaluation, and final deployment. Reports indicate the decision tools have been successfully implemented and were judged to be helpful in forecasting road closures and in reducing costs and personnel time in monitoring the roadway.

Liability and Traffic Control Considerations for Low Water Stream Crossings, HR-218, 1981

The current shortage of highway funds precludes the immediate replacement of most of the bridges that have been evaluated as structurally deficient or functionally obsolete or both. A low water stream crossing (LWSC) affords an economical alternative to the replacement of a bridge with another bridge in many instances. However, the potential liability that might be incurred from the use of LWSCs has served as a deterrent to their use. Nor have guidelines for traffic control devices been developed for specific application to LWSCs. This research addressed the problems of liability and traffic control associated with the use of LWSCs. Input to the findings from this research was provided by several persons contacted by telephone plus 189 persons who responded to a questionnaire concerning their experience with LWSCs. It was concluded from this research that a significant potential for accidents and liability claims could result from the use of LWSCs. However, it was also concluded that this liability could be reduced to within acceptable limits if adequate warning of the presence of an LWSC were afforded to road users. The potential for accidents and liability could further be reduced if vehicular passage over an LWSC were precluded during periods when the road was flooded. Under these conditions, it is believed, the potential for liability from the use of an LWSC on an unpaved, rural road would be even less than that resulting from the continuing use of an inadequate bridge. The signs recommended for use in advance of an LWSC include two warning signs and one regulatory sign with legends as follows: FLOOD AREA AHEAD, IMPASSABLE DURING HIGH WATER, DO NOT ENTER WHEN FLOODED. Use of the regulatory sign would require an appropriate resolution by the Board of Supervisors having responsibility for a county road. Other recommendations include the optional use of either a supple mental distance advisory plate or an advisory speed plate, or both, under circumstances where these may be needed. It was also recommended HR-218 Liability & Traffic Control Considerations for Low Water Stream Crossings that LWSCs be used only on unpaved roads and that they not be used in locations where flooding of an LWSC would deprive dwelling places of emergency ground access.

Ice-Retardant Pavement, HR-290, 1991

During 1986, the City of Des Moines placed an experimental asphaltic concrete overlay containing an ice-retardant additive (Verglimit) on Euclid Avenue (U.S. Highway 6). Verglimit is a chemical multi-component deicer which is added to the surface course of an asphalt overlay. The additive was uniformly distributed through the mix at the asphalt plant, which allows exposure of the particles as the finished surface wears under traffic. During a snowfall, the exposed particles attract and absorb moisture creating a deicing solution which dampens the pavement. The Verglimit additive used on this project cost $1,180 per metric ton. The Verglimit was added at a rate of 6.3% by weight, which was 126 pounds per ton, or $66.38 per ton of hot mix asphalt. The purchase of Verglimit additive was funded by the Iowa Department of Transportation through a research project recommended by the Highway Research Advisory Board. The pavement surface experienced severe wetting due to the additive's affinity for water immediately after the project was completed and during periods of high humidity. This wetting created slippery conditions both on the project itself and where vehicles tracked the additive. The only way to remove the slipperiness was by flushing the street with water. The ice-retardant overlay appears to perform as expected in reducing the adherence of ice and snow, especially at temperatures just below freezing. It performs better in light snowfalls than in heavy ones. The ice retardant overlay is effective in eliminating thin coatings of ice due to freezing drizzle or widespread frost. The accident data showed a reduction in the number of snow and ice related accidents but due to the low number of this type of accident the results are inconclusive.

Evaluation of an International Barrier Corporation Barrier, HR-532, 1990

In 1986, the Iowa DOT installed 700 feet of International Barrier Corporation (IBC) barrier between the 1-235 eastbound off ramp and the adjacent eastbound loop on ramp at 8th Street in West Des Moines. It is a 3 foot 6 inch high sand-filled galvanized sheet metal barrier. The bid price on this project was $130 per lineal foot. It was evaluated annually for four years. During this time, there have been no severe accidents where vehicles hit the barrier. There are scrapes and dents indicating minor accidents. The barrier has performed very well and required no maintenance. Due to its initial cost, the IBC barrier is not as cost-effective as portland cement concrete barrier rails.

Access Management Awareness Program Phase II Report, TR-402, 1997

This report presents the results of a number of detailed Iowa access management case studies. Case studies were selected to provide a cross-section of locations and community sizes in Iowa as well as a variety of project types. Generally, access management projects completed during the mid-1990s were chosen as case studies. Projects ranging from driveway consolidation to full raised medians were analyzed on a before and after basis in terms of traffic safety, traffic operations, and adjacent business vitality. Sources of information used for the case study analysis included: road project files; traffic accident records; state sales tax records; and personal interviews of business owners, business customers, and local officials. The case study results from Iowa essentially confirm results of previous access management research from around the nation. Recent access in Iowa had significant, positive impacts in terms of traffic safety. The average reduction of annual accidents and accident rates on improved roadways was approximately 40%. Improvements in access management also led to significantly better roadway operations for most case studies. Although a small number of individual businesses do report sales losses and/or customer complaints once projects have been completed, access management projects in Iowa have not had an adverse impact on the majority of businesses located along them. In fact, some access management projects in Iowa seem to have contributed to an improved business environment along the corridors that have been improved. The results from the Iowa case studies presented in this report will be used to develop access management education materials for Iowa transportation professionals and other audiences interested in the impacts of access management.

Determination of Rumble Strip Effectiveness, HR-184, 1979

Rumble strips are patches of specially treated pavement surfaces which are designed to produce aural and tactile stimuli inside vehicles. The intent is to alert drivers and when desirable, cause them to slow down or come to a stop. Installations were made in a three-county area in Iowa to study rumble strip effectiveness as an accident reducing measure. The investigation of accidents at the various test sites showed that rumble strips were effective in reducing certain types of intersection accidents. Although no statistically significant effect of the saturation use was found on total accidents, there are indications that accidents may be reduced when used in low density i.e., rural type areas.

Iowa State Plan for Brain Injury 2013-2018

Traumatic Brain Injury (TBI) impacts the lives of thousands of Iowans each year. The effects of brain injury (often called the "silent epidemic" because resulting injury is often not visible to others) are cognitive, emotional, and social but may also result in physical disability. This state plan, created by the Governor's Advisory Council on Brain Injuries, is intended to provide guidance for brain injury services and prevention activities in Iowa. This is the fourth Iowa State Plan for Brain Injury. In addition to a statewide needs assessment, development of this plan included recommendations made by the Mental Health and Disability Services Redesign Brain Injury Work-group. For the first time in the history of TBI surveillance in Iowa, the numbers and rates of TBI deaths are decreasing, however hospitalizations and emergency department visits resulting from TBI are steadily increasing. This trend is likely due to the decrease in motor vehicle accidents and improved hospitalization protocols. Looking to the future, the Advisory Council on Brain Injuries identified goals in each of four focus areas. These focus areas are: #1 Individual and family access; dedicated to the enhancement of the lives of individuals with brain injuries and their families. #2 Service and support availability; #3 Service system enhancements; continued funding growth and public awareness campaigns that draw attention to the impact of brain injury. #4 Brain injury prevention; working to prevent and reduce three of the most common causes of brain injury are falls, no helmet use, and motor vehicle crashes.

Visibility and Speed Estimation of Iowa State Highway Commission Snowplows, HR-174, 1975

Many accidents involving Iowa snowplows have happened in recent years. This study investigated the influence of time of day, sex of subject, type of snowplow sign and snowplow speed on the criteria of oncoming driver reaction time and his estimate of snowplow speed. Film strips were made of a car passing a snow-Plow under various experimental conditions. These experimental movie strips were viewed in the laboratory by college student drivers who were asked to indicate their reaction time to slow down and to estimate the speed of the snowplow being passed. The generally best sign condition for the snowplow was to have a striped rear sign and a speed-proportional flashing light in addition to the standard rotating beacon on top of the truck. Several recommendations were made.

Winter Driving A Guide for Your Safety, January 17, 2012

The leading cause of death during winter storms is transportation accidents. Preparing your vehicle for the winter season and knowing how to react if stranded or lost on the road are the keys to safe winter driving.