Category Archives: Environment

New Project: Feasibility of LED Solar Street Lighting

The need for this research stems from documented safety benefits associated with roadway lighting and the growing challenges in maintaining traditional, wired lighting systems. While rural locations often face high costs for delivering grid power to remote intersections, recent increases in wire theft has affected communities across Minnesota. These issues highlight the importance of exploring alternative, resilient lighting solutions that can improve safety without relying heavily on conventional electrical infrastructure.

The research process will assess the feasibility of solar‑powered LED roadway luminaires through a combination of laboratory testing, field evaluation, and cost‑benefit analysis. Key activities include analyzing battery performance under cold‑weather conditions, studying how lower illumination levels affect safety and energy use, and examining the practical integration of solar panels and batteries into existing streetlight design. A field implementation at selected sites, including potentially rural intersections or trail locations, will help validate performance and identify operational considerations such as durability, code compliance, and vandalism resistance.

The expected benefits of this work include reduced lifecycle costs, lower environmental impacts, and decreased operational and maintenance demands. Solar‑powered streetlights eliminate the need for grid‑based electricity, reduce wiring infrastructure vulnerable to theft, and offer long‑term savings over a planned service life. Environmental gains are anticipated through reduced energy consumption and lower CO2 emissions, while improved lighting reliability and appropriate illumination levels are expected to support nighttime safety and reduce crash risks statewide.

“This project will provide unbiased, objective research using equipment, methods, and people that would otherwise be unavailable to local government,” said Nick Peterson, city engineer for Saint Paul Public Works. “As a result, Minnesota cities and counties will learn effective strategies for implementing solar-powered street lighting in our cold climate.”

The Objectives:

  1. Test energy storage capacity of Lithium-ion battery under different temperatures. The battery energy storage capacity is a critical component in the feasibility of solar powered LED street lighting in cold northern climates.
  2. Explore the implications of running the streetlights at a lower brightness on power conservation and traffic safety. The balance between the energy demand for street lighting and the traffic safety is critical to an optimized solar powered LED streetlight that has a minimal solar panel and battery size and less effect on the existing streetlight infrastructure design.
  3. Conduct a comprehensive cost-benefit analysis considering material, labor, and maintenance costs for the installation and use of the solar-powered LED luminaire system, along with the benefits, such as the saved utility costs, the avoided costs of nighttime crashes, and the associated environmental benefits, such as the associated reduction of CO2 emissions.
  4. Provide MnDOT with guidelines and specifications on solar-powered LED streetlight implementation details.

Project Details:

  • Start Date: 07/16/2025
  • Estimated Completion Date: 05/31/2027
  • Funding: Local Road Research Board
  • Principal Investigator: Mijia Yang
  • Co-Principal Investigators: Xiangfa Wu and Yao Yu
  • Technical Liaison:  Nick Peterson

Details of the research study work plan and timeline are subject to change.

To receive email updates about this project, visit MnDOT’s Office of Research & Innovation to subscribe.

Mitigating Surface Tenting to Improve Road Quality

Transverse cracking and tenting are significant problems for asphalt pavements, especially in colder climates where the asphalt layer contracts during winter conditions. While the impacts of frost on roads are generally known, more data is needed about treatments to mitigate tenting and the influence of base layers on tenting behavior. This project examined the effectiveness of pavement treatment options and identified primary causes of tenting to help state and local engineers limit future tenting.

Continue reading Mitigating Surface Tenting to Improve Road Quality →

Reducing Phosphorus Pollution from Ponds

Ponds and historic wetlands are essential for preventing excessive phosphorus from reaching downstream waters. These systems remove solids, nutrients, metals and hydrocarbons from stormwater runoff as particles settle to the bottom. However, low oxygen levels in the water can cause phosphorous to be released from bottom sediments. This project examined the effectiveness of strategies to limit that release and reduce negative downstream impacts.

Continue reading Reducing Phosphorus Pollution from Ponds →

Protecting Wildlife Along Minnesota Roads

This week is Wildlife Casualty Count Week of Action in Minnesota. It highlights the impacts transportation systems have on wildlife and raises awareness of wildlife deaths resulting from vehicle collisions. Information about this effort can be found at: Wildlife Casualty Count Week

At MnDOT, we are committed to protecting wildlife through established practices and thoughtful planning. MnDOT works to minimize and mitigate impacts to protected fish, wildlife, and plant species in the design and construction of transportation projects. Read more about MnDOT’s commitment to protected species here: Wildlife – Environmental Stewardship

MnDOT’s Office of Research & Innovation supports research projects that advance wildlife protection and environmental conservation. These projects help inform how wildlife considerations are incorporated into transportation planning and construction. Explore projects guiding this work below:

Follow MnDOT’s Office of Research & Innovation to receive the latest updates in transportation research.

Goats can play a role in multi-pronged restoration of buckthorn-invaded woodlands

Reprinted from MnLTAP News, May 4, 2026

Goats are increasingly being used in efforts to manage invasive common buckthorn in Midwestern woodlands. New research demonstrates when and how they are best used.

Continue reading Goats can play a role in multi-pronged restoration of buckthorn-invaded woodlands →

CTS Webinar: Species from Feces—A New Tool to Identify Bats in Culverts and on Bridges

Wednesday, April 22, 2026, 12:00–1:30 pm, Virtual

About the Webinar

Bats frequently use bridges and culverts as roosting habitat, creating challenges for transportation agencies working to balance infrastructure needs with environmental compliance. Traditional visual surveys can be limited, especially when bats are hidden within structures or present only intermittently. 

This webinar will highlight ongoing research exploring the use of DNA analysis from bat feces (guano) as a noninvasive method to identify bat species occupying culverts and bridges. Speaker Ron Moen will discuss how this approach works, share early findings from field applications, and explore how the results could support more efficient environmental review, project planning, and species protection efforts for transportation agencies.

It is being held in conjunction with a CTS Environment and Energy in Transportation Council meeting.

Speaker

Ron Moen is an associate professor in the Department of Biology at the University of Minnesota Duluth and a senior research associate with the Natural Resources Research Institute’s Center for Water and the Environment. His research focuses on mammalian ecology, including habitat use, movement patterns, and predator–prey interactions, often using GPS radiotelemetry. His current work includes studies on moose, Canada lynx, American marten, wood turtles, bats, and other wildlife, as well as projects related to climate change impacts and carnivore monitoring in the Upper Midwest.

Registration

This webinar is free, but registration is required. Once you have registered, you will receive an email confirmation with a Zoom link. The link should not be shared with others; it is unique to you.

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Species From Feces: A New Tool to Identify Bats in Culverts and on Bridges

New Project: Engineering Post-Construction Soil Composition to Support Resilient Stormwater Management

Post-construction soils can produce much higher stormwater runoff rates than pre-construction or typical vegetated soils. Poor soil conditions can hinder the establishment of vegetation and carry large volumes of runoff, sediment, and nutrient loads to local waters. Organic soil amendments (composts) may support post-construction vegetative growth by boosting soil structure, nutrient availability, and water holding capacity.

This research aims to define targeted pre-construction soil health baselines, determine optimized design and field implementation inputs that return soils to baseline health indices using organic amendments, and identify how these inputs can benefit transportation requirements and resilient stormwater treatment.

The results may facilitate the quantification of benefits provided through soil health restoration and the development of implementable guidance for roadside soil health restoration techniques.

“This research project will help us understand how implementing soil health practices can improve the performance of roadside vegetation establishment resulting in MnDOT being able to close out construction contracts and stormwater permits sooner,” said Warren Tuel, Natural Resources Program Coordinator with MnDOT’s Office of Environmental Stewardship. “There are also significant potential stormwater benefits of soil health practices including increased infiltration, improved treatment of pollutants present in highway stormwater runoff. The improved management of stormwater will result in improved water quality of runoff from MnDOT highway systems resulting in greater protection of the many water resources here in Minnesota.”

The objectives are:

  1. Evaluate resilience to water availability through organic amendment (e.g., compost) addition through greenhouse stormwater experiments
  2. Optimize amendment loadings based on resilience
  3. Develop a “recipe” for improving the health of poor soils based on soil health measurements, by amending the soil with compost or other organics

Project Details

  • Start Date: 05/16/2025
  • Estimated Completion Date: 06/30/2027
  • Funding: MnDOT
  • Principal Investigator: Bora Cetin
  • Co-Principal Investigators: Angela Farina
  • Technical Liaison: Warren Tuel

Details of the research study work plan and timeline are subject to change.

To receive email updates about this project, visit MnDOT’s Office of Research & Innovation to subscribe.

Identifying Factors That Affect Stormwater Basin Performance

Stormwater basins are used to control runoff, prevent flooding and limit pollutants from reaching rivers, lakes and other large bodies of water. MnDOT monitors and maintains more than 400 infiltration and filtration basins statewide, and that number continues to grow. Identifying indicators of needed maintenance will increase management efficiency and basin performance. Field research at 28 basins identified basin age and silt content as two important factors to consider when planning inspections and taking corrective actions.

Continue reading Identifying Factors That Affect Stormwater Basin Performance →

Beyond the border: Canadian studies consider permeable pavement, climate change impacts on deicing operations

Reprinted from MnLTAP News, November 17, 2025

The 2025 Salt Symposium highlighted two studies from Canada, one comparing salt applications on permeable and asphalt surfaces and another considering the impact of climate change on municipal operations. Hosted by Bolton & Menk, the August 5 Salt Symposium brought together professionals from throughout the world to share research, projects, and approaches for chloride management.

Continue reading Beyond the border: Canadian studies consider permeable pavement, climate change impacts on deicing operations →

Developing Biochar Specifications for Stormwater Management 

Effective stormwater management helps keep roadway contaminants from entering Minnesota’s lakes and streams. Management practices include soil and vegetation in roadside bioretention systems that filter heavy metals and hydrocarbons created by vehicles. Based on other studies, retention and transformation of roadside pollutants should be improved by biochar application to existing or engineered soils. Abundant sources of biomass can be used to produce biochar, a soil amendment with numerous benefits. MnDOT and local agencies identified biochar specifications for effective use in stormwater treatment to support the next phase of testing and development of biochar design guidance. 

Continue reading Developing Biochar Specifications for Stormwater Management  →