Maximized Utility of the Global Positioning System, HR-316, 1991

This report describes a project begun in January 1989 and completed December 1990, with the primary objective of obtaining sufficiently accurate horizontal and vertical control by using Global Positioning System (GPS) for highway applications. The ISU research group studied the operations of the Ashtech GPS receiver in static, pseudo-static, kinematic, and pseudo-kinematic modes. By using the Electronic Distance Measuring Instrument (EDMI) Calibration Baseline at ISU, the GPS receiver was tested for distance measurement accuracy. It was found that GPS measurements differed from the baseline distance by about 5.3 mm. Four projects were undertaken to further evaluate and improve the horizontal as well as the vertical accuracies of the GPS receiver -- (1) The Campus Project: with all points concentrated within a one-mile radius; (2) The Des Moines Project: a typical DOT project with all the points within a five-mile radius; (3) The Iowa Project: with all points within a 100-mile radius in the state of Iowa; and (4) The Mustang Project: an extension of the Iowa project, including a typical DOT project of about 10 miles within the inner 30 mile radius of the Iowa project.

Skid Resistance of the Secondary Road System in Iowa, MLR-77-1, 1977

The Iowa Department of Transportation has been conducting skid resistance tests on the paved secondary system on a routine basis since 1973. This report summarizes the data obtained through 1976 on 10,101 miles in 95 of the 99 counties in Iowa. A summary of the skid resistance on the secondary system is presented by pavement type and age. The data indicates that the overall skid resistance on this road system is excellent. Higher traffic roads (over 1000 vehicles per day) have a lower skid resistance than the average of the secondary roads for the same age and pavement type. The use of non-polishing aggregates in asphaltic concrete paving surface courses and transverse grooving of portland cement concrete paving on high traffic roads is recommended. The routine resurvey of skid resistance on the secondary road system on a 5-year interval is probably not economically justified and could be extended to a 10-year interval.

Policy for Accommodating and Adjustment of Utilities on the Primary Road System, 2012

This chapter covers initial placement, adjustment, and maintenance of utility facilities in, on, above or below the right-of-way of primary highways, including attachments to primary highway structures. It embodies the basic specifications and standards needed to ensure the safety of the highway user and the integrity of the highway. (2012 revision to 2005 policy.)

Policy of the Iowa Department of Transportation Highway Division For Accommodating Utilities on the Primary Road System, 1992

This chapter covers initial placement, adjustment, improvement, relocation, replacement and maintenance of utility facilities in, on, above or below the right-of-way over of primary highways, including attachments to primary highway structures. It embodies the basic specifications and standards needed, to ensure the safety of the highway user and the integrity of the highway. (1992 revision to 1990 policy.)

Policy for Accommodating and Adjustment of Utilities on the Primary Road System, 2005

This chapter covers initial placement, adjustment, and maintenance of utility facilities in, on, above or below the right-of-way of primary highways, including attachments to primary highway structures. It embodies the basic specifications and standards needed, to ensure the safety of the highway user and the integrity of the highway. (2005 revision to 1992 policy.)

Evaluation of the Confirmation Light System at Signalized Intersections in Medium to Large Iowa Communities to Reduce Red Light Running Violations”, TR-657, 2015

Red light running continues to be a serious safety concern for many communities in the United States. The Federal Highway Administration reported that in 2011, red light running accounted for 676 fatalities nationwide. Red light running crashes at a signalized intersections are more serious, especially in high speed corridors where speeds are above 35 mph. Many communities have invested in red light countermeasures including low-cost strategies (e.g. signal backplates, targeted enforcement, signal timing adjustments and improvement with signage) to high-cost strategies (e.g. automated enforcement and intersection geometric improvements). This research study investigated intersection confirmation lights as a low-cost strategy to reduce red light running violations. Two intersections in Altoona and Waterloo, Iowa were equipped with confirmation lights which targeted the through and left turning movements. Confirmation lights enable a single police officer to monitor a specific lane of traffic downstream of the intersection. A before-after analysis was conducted in which a change in red light running violations prior to- and 1 and 3 months after installation were evaluated. A test of proportions was used to determine if the change in red light running violation rates were statistically significant at the 90 and 95 percent levels of confidence. The two treatment intersections were then compared to the changes of red light running violation rates at spillover intersections (directly adjacent to the treatment intersections) and control intersections. The results of the analysis indicated a 10 percent reduction of red light running violations in Altoona and a 299 percent increase in Waterloo at the treatment locations. Finally, the research team investigated the time into red for each observed red light running violation. The analysis indicated that many of the violations occurred less than one second into the red phase and that most of the violation occurred during or shortly after the all-red phase.

Status of Females in the Juvenile Justice System Iowa, 2016

Young women in the juvenile justice system present with characteristics and experiences that differentiate them from their male counterparts. As such, the juvenile justice system in Iowa must consider these factors if it is to effectively and efficiently impact recidivism, rehabilitation and public safety.