Use of Reversions Report, Iowa Department of Transportation, 2005

Use of Reversions Report.

A Review of the Revitalize Iowa's Sound Economy Program, Administered by the Department of Transportation, July 1, 1986 through June 30, 2004

Other Audit Reports - Review

Report of Recommendations to the Iowa Department of Transportation on Review of Selected General and Application Controls over the Accounts Payable System, July 11, 2005 to August 3, 2005

State Audit Reports

Report of Recommendations to the Iowa Department of Transportation, June 30, 2005

State Audit Reports

Use of Reversions Report, Iowa Department of Transportation, 2005.

Use of Reversions Report

2007-2011 Iowa Transportation Improvement Program

This document was prepared by the Iowa Department of Transportation to inform Iowans of planned investments in the state's transportation system over the next five years.

Iowa Department of Transportation Office of Contracts Letting Summary, July 1, 2005 thru June 30, 2006

Pursuant to the Code section 307.12(14)the DOT is providing the summary of contracts let from July 1, 2005 to June 20, 2006.

Iowa Department of Transportation Fiscal Year 2006 Report of Savings by Using Video Conferencing Through Iowa Communications Network, January 2007

Pursuant to Chapter II 84 Acts and Joint Resolutions enacted at the 1994 Regular Session of the 75th General Assembly of the State of Iowa - Code section 8D.10 Report of Savings by State Agencies Iowa Code section 8D.10 requires that certain state agencies prepare an annual report to the General Assembly certifying the identified savings associated with that state agency’s use of the Iowa Communications Network (ICN). This report covers estimated cost savings related to video conferencing via ICN for the Iowa Department of Transportation (DOT). In FY 2006, the DOT conducted two sessions utilizing ICN’s video conferencing system which resulted in $13,017 in estimated savings to the DOT.

Living Snow Fences, 2006

Blowing snow can cause significant problems for mobility and safety during winter weather in three distinct ways. It may drift onto the road, thus requiring almost continuous plowing while the wind is blowing (which may occur when a given winter storm is over). Snow may drift onto wet pavement (perhaps caused by ice control chemicals) and dilute out the chemicals on the road, creating ice on the road. And sufficient blowing snow can cause a major deterioration in visibility on the road, a factor which has been shown to be significant in winter crashes. The problem of blowing snow can be very effectively addressed by creating a snow storage device upwind of the road that requires protection from snow drifting. Typically, these storage devices are fences. Extensive design guidance exists for the required height and placement of such fences for a given annual snowfall and given local topography. However, the design information on the placement of living snow fences is less complete. The purpose of this report is to present the results of three seasons of study on using standing corn as snow fences. In addition, the experience of using switch grass as a snow storage medium is also presented. On the basis of these experimental data, a design guide has been developed that makes use of the somewhat unique snow storage characteristics of standing corn snow fences. The results of the field tests on using standing corn showed that multiple rows of standing corn store snow rather differently than a traditional wooden snow fence. Specifically, while a traditional fence stores most of the snow downwind from the fence (and thus must be placed a significant distance upwind of the road to be protected, specifically at least 35 times the snow fence height) rows of standing corn store the majority of the snow within the rows. Results from the three winters of testing show that the standing corn snow fences can store as much snow within the rows of standing corn as a traditional fence of typical height for operation in Iowa (4 to 6 feet) can store. This finding is significant because it means that the snow fences can be placed at the edge of the farmer’s field closest to the road, and still be effective. This is typically much more convenient for the farmer and thus may mean that more farmers would be willing to participate in a program that uses standing corn than in traditional programs. ii On the basis of the experimental data, design guidance for the use of standing corn as a snow storage device in Iowa is given in the report. Specifically, it is recommended that if the fetch in a location to be protected is less than 5,000 feet, then 16 rows of standing corn should be used, at the edge of the field adjacent to the right of way. If the fetch is greater than 5,000 feet, then 24 rows of standing corn should be used. This is based on a row spacing of 22 inches. Further, it should be noted that these design recommendations are ONLY for the State of Iowa. Other states of course have different winter weather and without extensive further study, it cannot be said that these guidelines would be effective in other locations with other winter conditions.

Go! Exploring the World of Transportation Magazine, January-February, 2007

Go! is a free, online magazine for teens and young adults that explores the world of transportation and the careers they can find there. The January-February 2007 issue focused on the theme of winter work.

Department of Transportation Performance Plan, Iowa Department of Transportation, 2007

Performance plan for Iowa Department of Transportation.

Lane Closure Policy Development, Enforcement, and Exceptions: A Survey of Seven State Transportation Agencies, February 2007

Traffic volume increases and an aging infrastructure create the need for reconstruction, rehabilitation, and maintenance of existing facilities. As more motorists feel that delays should be minimal during highway renewal projects, lane closures that reduce capacity through the work zone should not create unreasonable delays. In order to facilitate the determination of when a lane closure is permitted during the day, some state transportation agencies (STAs) have developed lane closure policies, or strategies, that they use as guidance in determining daily permitted lane closure times. Permitted lane closure times define what times of the day, week, or season a lane closure is allowed on a facility and at a specific location or segment. This research addresses the lane closure policies of several STAs that were reputed to have good lane closures policies or strategies and that were selected by the project advisory committee for further research.

Secondary Accident Data Fusion for Assessing Long-Term Performance of Transportation Systems, 2007

Secondary accident statistics can be useful for studying the impact of traffic incident management strategies. An easy-to-implement methodology is presented for classifying secondary accidents using data fusion of a police accident database with intranet incident reports. A current method for classifying secondary accidents uses a static threshold that represents the spatial and temporal region of influence of the primary accident, such as two miles and one hour. An accident is considered secondary if it occurs upstream from the primary accident and is within the duration and queue of the primary accident. However, using the static threshold may result in both false positives and negatives because accident queues are constantly varying. The methodology presented in this report seeks to improve upon this existing method by making the threshold dynamic. An incident progression curve is used to mark the end of the queue throughout the entire incident. Four steps in the development of incident progression curves are described. Step one is the processing of intranet incident reports. Step two is the filling in of incomplete incident reports. Step three is the nonlinear regression of incident progression curves. Step four is the merging of individual incident progression curves into one master curve. To illustrate this methodology, 5,514 accidents from Missouri freeways were analyzed. The results show that secondary accidents identified by dynamic versus static thresholds can differ by more than 30%.

Fiscal Year 2008-2012 Iowa Transportation Improvement Program

This document was prepared by the Iowa Department of Transportation to inform Iowans of planned investments in the state's transportation system over the next five years.

Audit report on the Iowa Department of Transportation for the year ended June 30, 2006

Audit report on the Iowa Department of Transportation for the year ended June 30, 2006