Evaluation of Temporary Ramp Metering for Work Zones, 2012

Ramp metering has been successfully implemented in many states to improve traffic operations on freeways. Studies have documented the positive mobility and safety benefits of ramp metering. However, there have been no studies on the use of ramp metering for work zones. This report documents the results from the first deployment of temporary ramp meters in work zones in the United States. Temporary ramp meters were deployed at seven urban short-term work zones in Missouri. Safety measures such as driver compliance, merging behavior, and speed differentials were extracted from video-based field data. Mobility analysis was conducted using a calibrated simulation model and the total delays were obtained for under capacity, at capacity, and over capacity conditions. This evaluation suggests that temporary ramp meters should only be deployed at work zone locations where there is potential for congestion and turned on only during above-capacity conditions. The compliance analysis showed that non-compliance could be a major safety issue in the deployment of temporary ramp meters for under-capacity conditions. The use of a three-section instead of a traditional two-section signal head used for permanent ramp metering produced significantly higher compliance rates. Ramp metering decreased ramp platoons by increasing the percentage of single-vehicle merges to over 70% from under 50%. The accepted-merge-headway results were not statistically significant even though a slight shift towards longer headways was found with the use of ramp meters. Mobility analysis revealed that ramp metering produced delay savings for both mainline and ramp vehicles for work zones operating above capacity. On average a 24% decrease in total delay (mainline plus ramp) at low truck percentage and a 19% decrease in delay at high truck percentage conditions resulted from ramp metering.

Audit report on America’s Agricultural Industrial Heritage Landscape, Inc., d/b/a Silos and Smokestacks National Heritage Area and Silos and Smokestacks Natural Heritage Area Foundation in Waterloo, Iowa for the years ended December 31, 2013 and 2012

Audit report on America’s Agricultural Industrial Heritage Landscape, Inc., d/b/a Silos and Smokestacks National Heritage Area and Silos and Smokestacks Natural Heritage Area Foundation in Waterloo, Iowa for the years ended December 31, 2013 and 2012

Audit report on America’s Agricultural Industrial Heritage Landscape, Inc., d/b/a Silos and Smokestacks National Heritage Area and Silos and Smokestacks Natural Heritage Area Foundation in Waterloo, Iowa for the years ended December 31, 2014 and 2013

Audit report on America’s Agricultural Industrial Heritage Landscape, Inc., d/b/a Silos and Smokestacks National Heritage Area and Silos and Smokestacks Natural Heritage Area Foundation in Waterloo, Iowa for the years ended December 31, 2014 and 2013

Temporary Speed Hump Impact Evaluation, 2002

The main objective of this research was to evaluate the impact of temporary speed humps and speed tables on vehicle speeds, vehicle speed profiles, and traffic volumes along local and/or collector streets in several rural Iowa cities. A 25 mile per hour (mph) temporary speed hump and a 30 mph temporary speed table, both made of recycled rubber, were purchased to test the impact of temporary devices. Two cities volunteered and the speed hump/table was installed on two test streets in the city of Atlantic (Roosevelt Drive and Redwood Drive) and one test street in the city of Le Claire (Canal Shore Drive). The speed hump was installed first and then converted to a speed table. Each device was installed for a period of at least two weeks at the same location. Speed, volume, and resident opinion data were then collected and evaluated.

Temporary Traffic Control Handbook, TR-694, 2016

This handbook provides a broad, easy to understand reference for temporary traffic control in work zones, addressing the safe and efficient accommodation of all road users: motorists, bicyclists, pedestrians, and those with special needs. When impacting a pedestrian facility, provide ten calendar days advance notification to the local jurisdiction and the National Federation of the Blind of Iowa (www.nfbi.org). The information presented is based on standards and guidance in the 2009 Edition of the Manual on Uniform Traffic Control Devices (MUTCD). References to the MUTCD sign designations in this handbook are shown in parentheses, e.g. (W20-1). Not all the recommendations in this handbook will apply to every circumstance faced by local agencies, and each unique situation may not be addressed. Modifications of the typical applications in this handbook will be required to adapt to specific field conditions. Therefore, use engineering judgment, seeking the advice of experienced professionals and supervisors in difficult and complex interpretations. This handbook can be used as a reference for temporary traffic control in work zones on all city or county roadways. However, always check contract documents and local agency requirements for any pertinent modifications.

Audit report on America’s Agricultural Industrial Heritage Landscape, Inc., d/b/a Silos and Smokestacks National Heritage Area and Silos and Smokestacks Natural Heritage Area Foundation in Waterloo, Iowa for the years ended December 31, 2015 and 2014

Audit report on America’s Agricultural Industrial Heritage Landscape, Inc., d/b/a Silos and Smokestacks National Heritage Area and Silos and Smokestacks Natural Heritage Area Foundation in Waterloo, Iowa for the years ended December 31, 2015 and 2014