Evaluation of Variable Advisory Speed Limits in Work Zones, TPF-5(081), 2013

Variable advisory speed limit (VASL) systems could be effective at both urban and rural work zones, at both uncongested and congested sites. At uncongested urban work zones, the average speeds with VASL were lower than without VASL. But the standard deviation of speeds with VASL was higher. The increase in standard deviation may be due to the advisory nature of VASL. The speed limit compliance with VASL was about eight times greater than without VASL. At the congested sites, the VASL were effective in making drivers slow down gradually as they approached the work zone, reducing any sudden changes in speeds. Mobility-wise the use of VASL resulted in a decrease in average queue length, throughput, number of stops, and an increase in travel time. Several surrogate safety measures also demonstrated the benefits of VASL in congested work zones. VASL deployments in rural work zones resulted in reductions in mean speed, speed variance, and 85th percentile speeds downstream of the VASL sign. The study makes the following recommendations based on the case studies investigated: 1. The use of VASL is recommended for uncongested work zones to achieve better speed compliance and lower speeds. Greater enforcement of regulatory speed limits could help to decrease the standard deviation in speeds; 2. The use of VASL to complement the static speed limits in rural work zones is beneficial even if the VASL is only used to display the static speed limits. It leads to safer traffic conditions by encouraging traffic to slow down gradually and by reminding traffic of the reduced speed limit. A well-designed VASL algorithm, like the P5 algorithm developed in this study, can significantly improve the mobility and safety conditions in congested work zones. The use of simulation is recommended for optimizing the VASL algorithms before field deployment.

Cost-Benefit Analysis of Sequential Warning Lights in Nighttime Work Zone Tapers, TPF-5(081), 2011

Improving safety at nighttime work zones is important because of the extra visibility concerns. The deployment of sequential lights is an innovative method for improving driver recognition of lane closures and work zone tapers. Sequential lights are wireless warning lights that flash in a sequence to clearly delineate the taper at work zones. The effectiveness of sequential lights was investigated using controlled field studies. Traffic parameters were collected at the same field site with and without the deployment of sequential lights. Three surrogate performance measures were used to determine the impact of sequential lights on safety. These measures were the speeds of approaching vehicles, the number of late taper merges and the locations where vehicles merged into open lane from the closed lane. In addition, an economic analysis was conducted to monetize the benefits and costs of deploying sequential lights at nighttime work zones. The results of this study indicates that sequential warning lights had a net positive effect in reducing the speeds of approaching vehicles, enhancing driver compliance, and preventing passenger cars, trucks and vehicles at rural work zones from late taper merges. Statistically significant decreases of 2.21 mph mean speed and 1 mph 85% speed resulted with sequential lights. The shift in the cumulative speed distributions to the left (i.e. speed decrease) was also found to be statistically significant using the Mann-Whitney and Kolmogorov-Smirnov tests. But a statistically significant increase of 0.91 mph in the speed standard deviation also resulted with sequential lights. With sequential lights, the percentage of vehicles that merged earlier increased from 53.49% to 65.36%. A benefit-cost ratio of around 5 or 10 resulted from this analysis of Missouri nighttime work zones and historical crash data. The two different benefitcost ratios reflect two different ways of computing labor costs.

Iowa Power Fund Summary of Economic Impact Study,

A newly completed study commissioned by the Iowa Office of Energy Independence shows increased jobs, tax revenue and economic activity as a result of Iowa Power Fund projects. The analysis is divided into two parts. Part I assesses the specific impacts of projects that have been funded directly. Part II offers an analysis of the long term impacts when projects are successfully replicated.

Iowa Department of Economic Development Performance Plan, FY2014

Agency Performance Plan, Iowa Department of Economic Development

Iowa Office of Energy Independence Iowa Power Fund Summary of Economic Impact Study, December 16, 2010

A newly completed study commissioned by the Iowa Office of Energy Independence shows increased jobs, tax revenue and economic activity as a result of Iowa Power Fund projects. The analysis is divided into two parts. Part I assesses the specific impacts of projects that have been funded directly. Part II offers an analysis of the long term impacts when projects are successfully replicated.

Audit report on the Cedar County Economic Development Commission for the year ended June 30, 2013

Audit report on the Cedar County Economic Development Commission for the year ended June 30, 2013

Development of an Economic Dust Palliative for Limestone Surfaced Secondary Roads, HR-297, 1990

This research project was directed at laboratory and field evaluation of sodium montmorillonite clay (bentonite) as a dust palliative for limestone surfaced secondary roads. It had been postulated that the electrically charged surfaces of the clay particles could interact with the charged surfaces of the limestone and act as a bonding agent to agglomerate fine (-#200) particulates and also to band the fine particulates to larger (+#200) limestone particles. Laboratory testing using soda ash dispersed bentonite treatment of limestone fines indicated significant improvement of compressive strength and slaking characteristics. It was recommended that the project proceed to field trials and test roads were constructed in Dallas and Adair counties in Iowa. Soda ash dispersed bentonite solutions can be field mixed and applied with conventional spray distribution equipment. A maximum of 1.5% bentonite(by weight of aggregate)can be applied at one time. Higher applications would have to be staged allowing the excess moisture to evaporate between applications. Construction of higher application treatments can be accomplished by adding dry bentonite to the surfacing material and then by dry road mixing. The soda ash water solution can then be spray applied and the treated surfacing material wet mixed by motor graders to a consistency of 3 to 4 inch slump concrete. Two motor graders working in tandem can provide rapid mixing for both methods of construction. Calcium and magnesium chloride treatments are 2 to 3 times more effective in dust reduction in the short term (3-4 months) but are prone to washboarding and potholing due to maintenance restrictions. Bentonite treatment at the 2-3% level is estimated to provide a 30-40% dust reduction over the long term(18-24 months). Normal maintenance blading operations can be used on bentonite treated areas. Vehicle braking characteristics are not adversely affected up to the 3.0% treatment level. The bentonite appears to be functioning as a banding agent to bind small particulates to larger particles and is acting to agglomerate fine particles of limestone. This bonding capability appears recoverable from environmental effects of winter, and from alternating wet and dry periods. The bentonite appears to be able to interact with new applications of limestone maintenance material and maintains a dust reduction capability. Soda ash dispersed bentonite treatment is approximately 10 times more cost effective per percent dust reduction than conventional chloride treatments with respect to time. However,the disadvantage is that there is not the initial dramatic reduction in dust generation as with the chloride treatment. Although dust is reduced 30-40% after treatment there is still dust being generated and the traveling public or residents may not perceive the reduction.

The Economic Potential of the Spergen Formation in Seven Southeastern Iowa Counties, HR-189, 1978

The middle Mississippian (Meramec Series) units include the Spergen Formation, the St. Louis Limestone and the Ste. Genevieve Formation which outcrop sporadically within a curvilinear subcrop band trending through southeastern and central Iowa. Studies of these units as they occur in Iowa have been cursory in the past, especially with regard to the lowermost occurring Meramecan unit, the Spergen Formation. The Spergen Formation, as it occurs in southeastern Iowa is being considered as a desirable concrete aggregate source. At present, the depth of occurrence, thickness variations and geographic extent are very poorly known and the nature of lithologic variation in Iowa is obscure. Due to a paucity of information of its thickness, extent and nature of rapid lateral facies variations, the full economic potential of the unit has not been realized in some areas of southeastern Iowa. This is especially disheartening in view of the decline of acceptable concrete aggregate source materials in southeastern Iowa. This report is an attempt to synthesize subsurface and surface data in order to present a more coherent picture of the depth, thickness and lithologic variations of the Spergen Formation. Recommendations have been made for the exploration of specific areas within the field area for future development of surface quarrying and subsurface mining operations where thickness, lithology and depth characteristics deem consideration. Due to the lack of adequate data points in some quadrants of the field area, some of the recommendations are drawn on rather tenuous grounds, but a concerted effort has been made to be conservative in these judgements.

Report on the Iowa Economic Development Authority for the year ended June 30, 2013

Report on the Iowa Economic Development Authority for the year ended June 30, 2013

An Assessment of Traffic Safety in Urban Deer Herd Management Zones in Iowa, 2010

Many states are striving to keep their deer population to a sustainable and controllable level while maximizing public safety. In Iowa, measures to control the deer population include annual deer hunts and special deer herd management plans in urban areas. While these plans may reduce the deer population, traffic safety in these areas has not been fully assessed. Using deer population data from the Iowa Department of Natural Resources and data on deer-vehicle crashes and deer carcass removals from the Iowa Department of Transportation, the authors examined the relationship between deer-vehicle collisions, deer density, and land use in three urban areas in Iowa that have deer management plans in place (Cedar Rapids, Dubuque, and Iowa City) over the period 2002 to 2007. First, a comparison of deer-vehicle crash counts and deer carcass removal counts was conducted at the county level. Further, the authors estimated econometric models to investigate the factors that influence the frequency and severity of deer-vehicle crashes in these zones. Overall, the number of deer carcasses removed on the primary roads in these counties was greater than the number of reported deervehicle crashes on those roads. These differences can be attributed to a number of reasons, including variability in data reporting and data collection practices. In addition, high rates of underreporting of crashes were found on major routes that carry high volumes of traffic. This study also showed that multiple factors affect deer-vehicle crashes and corresponding injury outcomes in urban management zones. The identified roadway and non-roadway factors could be useful for identifying locations on the transportation system that significantly impact deer species and safety and for determining appropriate countermeasures for mitigation. Efforts to reduce deer density adjacent to roads and developed land and to provide wider shoulders on undivided roads are recommended. Improving the consistency and accuracy of deer carcass and deer-vehicle collision data collection methods and practices is also desirable.

Iowa Department of Economic Development Strategic Plan, March 27, 2012

This report outlines the strategic plan for Iowa Department of Economic Development, goals and mission.

A Smartphone-Based Prototype System for Incident/Work Zone Management Driven by Crowd-Sourced Data, 2015

This project develops a smartphone-based prototype system that supplements the 511 system to improve its dynamic traffic routing service to state highway users under non-recurrent congestion. This system will save considerable time to provide crucial traffic information and en-route assistance to travelers for them to avoid being trapped in traffic congestion due to accidents, work zones, hazards, or special events. It also creates a feedback loop between travelers and responsible agencies that enable the state to effectively collect, fuse, and analyze crowd-sourced data for next-gen transportation planning and management. This project can result in substantial economic savings (e.g. less traffic congestion, reduced fuel wastage and emissions) and safety benefits for the freight industry and society due to better dissemination of real-time traffic information by highway users. Such benefits will increase significantly in future with the expected increase in freight traffic on the network. The proposed system also has the flexibility to be integrated with various transportation management modules to assist state agencies to improve transportation services and daily operations.

Audit report on the Cedar County Economic Development Commission for the year ended June 30, 2014

Audit report on the Cedar County Economic Development Commission for the year ended June 30, 2014

Iowa Department of Economic Development Performance Plan, FY2015

Agency Performance Plan, Iowa Department of Economic Development

Report on the Iowa Economic Development Authority for the year ended June 30, 2014

Report on the Iowa Economic Development Authority for the year ended June 30, 2014