Each year, the American Association of State Highway and Transportation Officials (AASHTO) honors the best transportation research projects from each of its four regions with a prestigious High Value Research (HVR) award.  

As a member of Region 3, Iowa competes with eight other Midwestern states – Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Ohio, and Wisconsin. After winning 13 HVR awards, (including supplemental HVR awards) in the last 11 years, Iowa is looking to do it again in 2024.   
 
The projects Iowa has submitted for consideration this year are:
 

• Advanced Testing and Characterization of Iowa Soils and Geomaterials. The strength and durability of a pavement’s foundational layers are critical to a road's long-term performance. However, the standard tests that have traditionally been used to assess the characteristics of subgrade materials are not always sufficient for Iowa’s aggregates and soils. This study applied advanced testing methods to produce results that more accurately reflect field conditions.
   
• Evaluation of Otta Seal Surfacing for Low-Volume Roads in Iowa: Comprehensive Laboratory Evaluation and Characterization and Full-Scale Field Implementation. In a previous project, Iowa DOT constructed a low-volume road using Otta seal technology to evaluate its potential. This study evaluated the road’s performance and developed specifications for using Otta seal methods on Iowa’s roads in the future.
   
• Modernizing Utility Infrastructure Management: Early Identification and Location of Utility Facilities. As communities grow and become more connected, an increasing amount of utility infrastructure is placed below ground in the public right of way. To better manage these public spaces and improve safety and connectivity for everyone, Iowa DOT collaborated with a variety of public and private stakeholders to develop a database of these unseen pipes and cables and guidance for sharing and maintaining location information.
   
• Actionable Flood Warnings based on Ground-truth Data to Support Iowa DOT BridgeWatch Platform Functionality. With an accurate flood warning, Iowa DOT can take steps to protect the state’s bridges and minimize travel disruptions. However, many of the state’s flood-prone bridges are located outside of the current forecasting network. This research assessed Iowa’s current floodplain maps and developed a long-term plan for extending the forecasting technology to include all of the state’s at-risk bridges.

After reviewing all of the projects submitted by the Region 3 states, AASHTO’s Research Advisory Committee will recognize the winners at the committee’s summer meeting in July. The winning states will also participate in a poster session dedicated to high-value research projects at the annual meeting of the Transportation Research Board in Washington, DC in January 2025.

Learn more about the HVR Awards Iowa has won over the years. 

Culverts serve an important role in keeping water off a roadway and are often buried under or alongside a road. 

A variety of considerations go into designing the right culvert for its location and role in the broader transportation system.  

In Iowa, culverts are typically buried 5 to 10 feet under roadways. Some road projects, however, require burying culverts 20 to 35 feet beneath the surface to divert water. 

As soil characteristics and properties vary significantly across the state, the amount of weight of that a culvert must be able to support also varies. 

To better understand the complexities in determining earth pressure on a culvert, the Iowa Highway Research Board (IHRB) conducted a research project to monitor two newly constructed culverts over several seasons. 

The results will help engineers across the state continue to design culverts that perform well for years to come.   

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page.

Penetrating sealants show great promise for protecting concrete from the negative impacts of deicing salts.  

Many sealers are available on the market, each with different chemical compositions and performance attributes.  

The challenge for Iowa’s city and county engineers is selecting the appropriate sealer.  

Iowa DOT funded laboratory and field testing to better understand how to select the right sealant for each application and to determine the best way to evaluate the sealer’s effectiveness.  

As a result of this research, engineers have a better understanding of which types of sealers are formulated to address common durability problems.  

They also have a set of recommendations on the best tests for assessing key categories of sealers. Additional field testing is underway to assess the long-term impacts of sealers on concrete joints.  

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Each January, Iowa DOT staff travel to the Transportation Research Board (TRB) annual meeting in Washington D.C., to share ideas and research results and learn from others in the international transportation community.    

Learn more about Iowa’s work at the 2024 TRB meeting in our new interactive Storymap.

Behind every Iowa DOT research innovation is a real human being dedicated to helping ideas become reality. Here you can learn more about the Iowa DOT Research staff members and what makes them tick. 
 

Name: Lee Bjerke, Secondary Roads Research Engineer 
Number of years in this role: 1 
 
What do you do in the Research & Analytics Bureau?   

I am the Secondary Roads Research Engineer. My role is to be the liaison between the counties in Iowa, their engineers, and the Iowa Highway Research Board (IHRB). It is my responsibility to bring the ideas for research to the IHRB, work with the academics on research that benefits the counties and then help the counties to effectively implement the research. 
 
Have you always been drawn to research? What has your career path been like?   

I have always found research interesting. I have spent 23 years as the Winneshiek County Engineer and experienced first-hand the difficulty the counties face with upkeep and improving the secondary road systems. I served on various technical advisory committees and have implemented research such as Otta Seals, using railroad flat cars for short span bridges, and Internal Curing Concrete. One of the biggest issues I saw for counties was the damage done by the large rain events experienced by Iowa in recent years. I championed the research in using roads as impoundment structures to slow rainwater and reduce the damages they can cause. 
 
What’s your favorite part of your work?   

My favorite part of this job is seeing great ideas, regardless of where they come from, become a truly effective tool for the counties to use in improving the Secondary Road System. 

What initiative on the horizon do you think will make a big impact for the research bureau?   

I see two big ones: the AASHTO bridge rating software and the On-Road Impoundment structures. Both of these will have huge advantages to the public in ensuring their ability to traverse the roadways in Iowa in the most efficient and cost-saving manner possible. 
 
What do you like to do in your time off?   

My wife and I love the water. Boating is our favorite pastime; whether it is pulling kids on tubes, putzing along on a pontoon, or sitting in a chair on a beach, time on the water is easily our number one place to be. 

Traditionally, the criteria used for testing concrete mixtures are largely based on material strength and air content. But verifying that pavements are sustainable and long-lasting depends on other engineering properties. Iowa DOT led a multistate, multiyear effort to deploy new technologies that ensure high-quality pavements that require less maintenance over time. 

This research project involved comprehensive educational initiatives, pilot testing, and project support. As a result of this effort, Iowa DOT and 18 other states have improved concrete mix specifications and are using new performance-based testing technologies to deliver improved concrete pavements. 

Iowa DOT is also leading a follow-up project focused on handling concrete mixes at the construction site.  

This research gives agencies new and better tools to select effective performance-based specifications for pavements and overlays that perform well throughout their design life cycles.  

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Iowa’s aggregate roads are designed to keep rural communities connected and support the state’s farming economy. But freezing and thawing temperatures and use by heavy equipment can quickly damage the roads, requiring costly repair and maintenance every year.  

To make these roads more durable and longer-lasting, the Iowa Highway Research Board initiated a research project to test 13 different construction and maintenance techniques under real-world conditions for two years. The results give engineers in Iowa’s 99 counties greater flexibility when it comes to building these important roads and keeping them in good working condition.    

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Since September, Iowa DOT has launched seven new research projects to help advance transportation in the state. These initiatives include: 
 

• Sustainable Dust Suppressants for Gravel Roads - As vehicles and other heavy equipment travel along Iowa's gravel roads, the loose aggregates on the surface are often crushed and released into the air as fine particulates. Not only is less material left on the roads, but the airborne dust can lower drivers’ visibility and pose a serious health threat to road users and those living and working in the vicinity. This research, which will conclude in June 2025, aims to find a lower-cost and more environmentally friendly alternative to chemical stabilizers. Subscribe and receive project updates here.
   
• Connected Vehicle Technology for Road Weather Management - Existing road weather information systems collect data from various sources to help transportation agencies decide how, when, and where snowplows and other road maintenance resources are needed. Gaps in data coverage persist, however, and as the lead state of the Aurora pooled fund program Iowa DOT is working with other states to identify communication methods that effectively reach road users in real time. The research is expected to conclude in April 2024. Subscribe and receive project updates here.
   
• Crowdsourced road friction data - Keeping winter roads clear is resource intensive. In addition to costs for deicing materials, maintenance crews and equipment, state departments of transportation (DOTs) must have capabilities to deploy crews to the locations that need them the most. Road weather information systems, which measure actual road conditions, are expensive and provide limited spatial coverage. This research project, set to end in July 2024, will explore alternative sources for this valuable data. Subscribe and receive project updates here.

• Alerting Drivers to Adverse Road Conditions - Smartphones and onboard vehicle computers provide access to changing traffic patterns, road closures, and weather updates to help drivers make informed planning decisions. Iowa DOT envisions a high-tech system that could respond to a driver’s spoken request for this information, ensuring their focus remains on the road ahead. The research is expected to conclude in April 2025. Subscribe and receive project updates here.
   
• Winter Weather Road Condition Indices - State agencies protect travelers by providing up-to-date information on weather and road conditions. But climates vary significantly across the country, and there is currently no standardized guideline or index that connects these different state weather information systems. This gap raises concerns about driver safety and the response to weather events that affect multiple states. In this research, Iowa DOT will work with other state to investigate a uniform framework for indexing and communicating weather conditions to travelers. The project is expected to conclude in April 2025. Subscribe and receive project updates here.
   
• Assessing Roadway Safety Hardware - Safety hardware devices designed for use in roadways – such as barriers, breakaway signs, and crash cushions – undergo rigorous tests before they’re deployed on a roadway. Once on the road, collision and maintenance helps Iowa DOT assess the performance of these devices in real-world conditions. But data coming from a variety of sources, such as police and road maintenance crews, is often in different formats, making analysis challenging. This project, which is slated for completion in June 2024, will explore different data collection methods with the goal of developing a uniform process. Subscribe and receive project updates here.
   
• Improving Asset Management with Building Information Modeling - Transportation agencies generate volumes of data for designing, building, and maintaining transportation infrastructure. Iowa DOT leads the Building Information Modeling (BIM) for Infrastructure pooled fund, a multiyear effort that will develop recommended standards and processes for data exchange and digital workflows, geographic information systems applications, and asset inventories. The multiyear effort will develop recommended standards and processes for data exchange and digital workflows, geographic information systems applications, and asset inventories. The research is expected to conclude in December 2027. Subscribe and receive project updates here.
   

Want to get involved? Learn how Iowa DOT staff, industry stakeholders and members of the public can all help advance research in Iowa.  

And find out more about other Iowa DOT research efforts on the News & Publications page.

Iowa DOT recently applied for and won $3.5 million in federal funds to offset the costs of deploying new strategies.  

In August, the Federal Highway Administration awarded Iowa DOT two grants of $1 million each. The funds were provided under the Accelerated Innovation Deployment (AID) Demonstration program, which aims to help states quickly put innovative technologies into practice.  

Iowa DOT will use one of these grants to map the state’s system of gravel roads and identify areas where maintenance is needed most. The other award will go toward an asset management pilot project that will employ cutting-edge technologies to streamline processes in design, construction and maintenance.

In November, Iowa DOT was awarded an additional $1.5 million through the new Bipartisan Infrastructure Law program, which promotes technologies that reduce delays and cost overruns on transportation projects. As one of only 10 states to receive this funding, Iowa will use the funds to more effectively manage the state’s roads and bridges and serve as a model for other transportation agencies to follow in the future. 

Thanks to these federal funds, Iowa’s taxpayers will reap the benefits of having infrastructure that is cost-effective and high-performing without using the state’s budget to buy and deploy the necessary technologies.

Road friction sensors are high-tech tools that can quickly indicate slippery spots on roadways. Iowa DOT uses these sensors to better understand where salt or other deicing treatments are needed most; however, not all sensors produce the same results and their high cost means they can only be placed in key areas.  

To ensure the data collected is reliable and better understand road conditions in locations without sensors, Iowa DOT and 18 other states shared the costs of testing different sensors under simulated conditions and developing a computer model that can use weather and atmospheric data to infer the level of friction on the road. 

As more data is collected over the time, Iowa DOT will eventually be able to predict road friction anywhere in the state.    

This project was recently awarded a 2023 AASHTO High Value Research Award in the Safety Focus area. Learn more about this award highlighted in a recent News item. 

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

When a winter storm hits, time is of the essence as soon snow and ice can accumulate quickly and make for hazardous driving conditions.  

To help determine where snow-clearing and deicing treatments are needed most, Iowa DOT uses high-tech systems that monitor pavement surfaces and collect weather data. But conditions can vary, even between monitored locations. 

To make informed maintenance decisions even when data is unavailable, Iowa DOT led a coalition of 18 other states to investigate how still images taken by highway cameras might help.  

By manually labeling more than 20,000 images depicting wintry road conditions, researchers developed computer algorithms that can accurately differentiate between precipitation types and identify visibility challenges and ground conditions that may impact safety on the road’s surface. 

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Though specialized geotextile fabrics have been used in the construction of concrete highways in the United States for more than a decade, their long-term influence on the pavements has not been well understood.  

With a shared interest in learning more, Iowa DOT and 34 other states jointly commissioned a research project to study three different types of geotextiles and their long-term effects on concrete pavements.   

Using sections of Iowa’s Buchanan County Highway D-16 for testing, researchers evaluated stress and deformation of the concrete and compared road sections constructed with each of the geotextile fabrics and sections built using traditional methods.   

The resulting data gives the states greater insight when it comes to deciding which projects are well-suited for using geotextiles and demonstrated the reliability of the on-site testing techniques.  

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Traditionally designed roads and bridges can easily withstand the occasional flood. But as storms that used to happen once every 100 years become more frequent and extreme, Iowa DOT must ensure its infrastructure is ready. 

To determine how much water future storms may bring and how often flooding may occur, researchers studied historic flood events and used the data to develop a new online resource – the Iowa Flood Frequency and Projections Tool – that anyone can use.  

In addition to updating its building standards, Iowa DOT is already using this project’s findings to redesign segments along two major highway corridors in the state. 

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Did you know Iowa DOT Research is always working to explore new ways to make transportation safer, more efficient, and cost-effective? Learn more about some of our research efforts currently in progress: 

• VKelly Slipform Paving Test. The Vibrating Kelly Ball (VKelly) test may be a viable option for measuring the consistency of a pavement mixture onsite before road work begins. To ensure the test produces accurate and reliable results, Iowa is leading a multi-state study to outline the step-by-step process, simplify the testing equipment, and develop guidance for test operators. The study is expected to conclude in March 2025. Subscribe and receive project updates here. 

• Bridge Strike Detection and Reporting. When a vehicle hauling an oversized load strikes a bridge, it can cause significant damage and decrease the bridge’s life expectancy. Drivers often don’t stop or report the incident, leaving authorities unaware of the damage and taxpayers on the hook for repairs. To make sure damage is paid for by the offender, Iowa DOT is piloting a first-in-the nation research project to detect bridge strikes in real time and match the data with vehicle records. The research is expected to conclude in June 2024. Subscribe and receive project updates here. 

Want to get involved? Learn how Iowa DOT staff, industry stakeholders and members of the public can all help advance research in Iowa. 

And find out more about other Iowa DOT research efforts on the News & Publications page. 

National Truck Driver Appreciation Week, which takes place this year from September 10 - 26, is an annual reminder to thank the millions of professional drivers who transport the goods we rely on every day.  

While this special week helps highlight the important work that truckers do, Iowa DOT is committed to advancing truck driver safety and efficiency throughout the year. 

As a member of the Mid-America Freight Coalition (MAFC), Iowa DOT partners with nine other states – Illinois, Indiana, Kansas, Kentucky, Michigan, Minnesota, Missouri, Ohio, and Wisconsin – to identify common challenges and share the cost of researching effective solutions. These 10 states are all critical to the efficient and reliable movement of goods across the country as they are home to key interstates, inland waterways, the Great Lakes, rail lines, and air cargo facilities. By sharing technologies and best practices and cooperatively funding research, the MAFC supports planning, policy and operational activities that affect the entire nation.

Make sure to thank a truck driver for their tireless devotion to this important cause, and learn more about learn more about Iowa’s commitment to advancing freight research.

On October 30, 2019, a fire broke out in a homeless encampment beneath the I-29 northbound bridge over Perry Creek in Sioux City, Iowa. The fire intensified when a propane tank became engulfed in the flames.  

The incident gave Iowa DOT a real-life case study to better understand how visible damage may correlate with a bridge’s serviceability and strength, as well as an opportunity to update the agency’s tools and resources for evaluating fire damage in the future.  

The research results can help guide Iowa’s state and local transportation agencies as they make repair or replacement decisions for a bridge that’s damaged by fire.  

Learn more about this project in Iowa DOT’s new research brief.  

July was a busy month for Iowa to share the advancements it’s made in transportation research with peers from other states and around the world! 

From July 23-26, the Iowa Highway Research Board and Iowa County Engineer’s Association hosted the 13th International Conference on Low Volume Roads. 

The event only happens every four years, and this year’s conference in Cedar Rapids brought hundreds of attendees from more than 20 countries to exchange strategies and new technologies to address the challenges of planning, designing, constructing, operating and maintaining unpaved roads.  

It also offered an exciting opportunity for Iowa to demonstrate its innovations and state-of-the-art practices during a half-day tour of low-volume roads and the Sutliff Bridge in Johnson County.  

During that same week, from July 23-28, representatives from Iowa DOT Research and peers from other state transportation research programs gathered in Chattanooga, Tennessee for the American Association of State Highway and Transportation Officials (AASHTO) Research Advisory Committee (RAC) annual meeting.  

This national event offers a forum for states to discuss cutting-edge ideas and innovations in transportation research. The AASHTO RAC meeting is also where states’ research efforts are recognized and honored; Iowa DOT shared details of its project to train and improve computer models to predict where deicers should applied during winter storms, which was selected for one of AASHTO’s prestigious 2023 Supplemental High Value Research Award.   

This award marks the 13th HVR award (including supplemental HVR awards) that Iowa DOT Research has earned in the last 10 years.     

What does a year of transportation research look like? The Iowa DOT Research Section is proud to showcase its efforts in the new FY2022 Research At-A-Glance report.

With more than 200 research projects initiated, progressed or completed throughout the year, Iowa DOT gained valuable information on a variety of cutting-edge topics. From finding new uses for waste quarry fines ways to increasing the value of 3D Building Information Models, Iowa DOT Research continued to prioritize safety, mobility, sustainability, and technology to make transportation better for Iowans across the state.

The At-A-Glance also outlines the process Iowa DOT Research uses to gather research ideas, develop the research program, and work with partners to accomplish research objectives.

Interested in learning more about what Iowa DOT Research did in 2022, how it was done, and what’s coming next? Check out the full report!

Each year, Operation Safe Driver Week reminds us of the importance of safe driving practices.

Taking place this week, from July 9-15, the annual event aims to reduce crashes and save lives.

Road safety is a cause that’s near and dear to Iowa DOT Research. Through the Partnership for the Transformation of Traffic Safety Culture pooled fund, we’ve combined resources with 13 other similarly motivated state transportation agencies to find, fund and implement innovative strategies that increase safety for all road users.

By working together, the pooled fund has accomplished way more than an individual agency could on its own limited budget. From investigating the effects of cannabis use on driver behavior to identifying ways to reduce drivers’ cell phone use, the pooled fund has advanced the state of knowledge on dozens of road safety topics.

Learn more about Iowa DOT’s involvement with pooled funds and how it helps the agency make the most of every research investment. </p>

Do you have the next big idea in transportation research? Share it now to be considered before Iowa DOT’s Spring Research Cycle ends June 30th. 

Even if you don’t have a submission of your own, you can help others improve their ideas by voting or adding your comments.

Currently, ideas that were submitted in the Spring will be open for feedback until July 25, 2023. You can review, rate and comment on ideas in Open Feedback right now!

With three research cycles throughout the year, ideas are always in progress at Iowa DOT research. 
 
Check out the annual research calendar to see the year-round process and check the Ideas site often to find out what new ideas have been submitted and to provide your own!