This guidebook offers local agencies the information they need to make decisions on which type of culvert is best for their situation. It details the differences between reinforced concrete pipe, plastic (polypropylene) pipe, and corrugated metal pipe, and provides best practices for usage of the different materials. The guidance includes a summary of culvert use by local agencies in Minnesota, input from industry representatives providing recommended use, and a list of resources and design guides for each culvert type.

Crack treatment is an important preventative measure to extend a pavement’s serviceable life. Although the technique is simple, there are nuances that make it more of an art than science. This quick reference guide provides an overview of asphalt crack treatments, guidance on several FAQs, and a high-level summary of resources. It also synthesizes technical documents and interviews with local technical and industry representatives and is designed to be a resource that agencies can use to determine how to best implement their crack treatment program.

Snowplow operators often work in low-visibility conditions that can result in difficulty keeping the plow centered in the lane or identifying upcoming obstacles. A new system assists drivers in knowing their lane position and warns of approaching obstacles. After operators tested the system, researchers gathered feedback, revised the system and readied it for the next step in statewide deployment.

This extensive line of research received this year’s Robert C. Johns Research Partnership Award from the Center for Transportation Studies. Watch a video featuring the snowplow driver-assist system.

Researchers have developed a new tool to help local agencies better manage stormwater ponds to retain phosphorus by helping them identify which ponds are at risk for phosphorous release. The pond assessment tool was developed by identifying characteristics that correlate with high phosphorus levels. Leveraging previous research, investigators monitored several ponds over a two-year period. They used that data as well as data collected from approximately 230 ponds in the Twin Cities metro area. Local agencies can use the pond assessment tool to classify, prioritize and manage stormwater ponds.

St. Anthony Falls Laboratory researchers Prof. John Gulliver and Poornima Natarajan presented on this project in the City Engineers Association of Minnesota webinar, “Are Your Ponds Serving their Water Quality Function?” in June. A recording is now available online.

As autonomous vehicle technology evolves, transportation agencies want to understand how road maintenance and traffic operations may also need to evolve. New research begins to identify potential needs and further questions for winter road maintenance, work zones and traffic flow. Researchers conducted a series of tests on a new vehicle retrofitted with sensors, cameras and software to perceive and interpret the surrounding environment. The car could identify the distance to a vehicle ahead, the relative speed of the preceding vehicle and lane markings. It demonstrated mixed results when driving in different levels of traffic and varying levels of snow-covered highways and local roads. The research report details the full findings. Further investigations will continue into how AVs will interact with transportation infrastructure. 

The Minnesota Highway Freight Program has
$64 million in funding available for local road, rail, ports, intermodal and air freight projects. The funding can be used on any public road, railroad crossing or intermodal facility if the project provides a public freight benefit such as freight movement, safety, intermodal connections or efficiency across modes. Application deadline: Oct. 13, 2023.

St. Louis County received the 2023 National Build a Better Mousetrap “Smart Transformation Award” for its Remote Camera Installation project. The award was announced at the National LTAP & TTAP Association annual conference in July.

The project deployed 51 Barn Owl cameras throughout the county, enabling them to monitor road conditions in remote areas during winter storm events. Using a Local OPERA Program grant, St. Louis County also was able to modify the camera system to meet their needs.

The Minnesota Mousetrap Competition and Local OPERA program are sponsored by the Minnesota Local Road Research Board and administered by Minnesota LTAP.

Photo: Katherine Stanley, Minnesota LTAP, accepts a National Mousetrap Award on behalf of St. Louis County from Joe Conway, Federal Highway Administration Center for Local Aid Support.

We're looking forward to the Fall Maintenance Expo, Oct. 4 and 5, in St. Cloud. Be sure to stop by the LRRB/MN LTAP booth. We'll have our latest guidebooks and other information on LRRB projects.

Do you have a research idea? Make plans to attend the LRRB listening session at the Expo on Oct. 4 at 11:15 a.m. See you there!

See you at the LRRB listening sessions at the October Prescreening Meetings scheduled around the state! We're looking forward to hearing from city and county engineers and maintenance professionals about your challenges and ideas for future research.