Environment

Transportation and its supporting infrastructure have significant economic, social, and environmental impacts. Using more sustainable methods to design, construct, and preserve roads will better protect the environment and meet our ongoing needs. Mn/DOT and our partners in government, industry, and academia have been researching and implementing ways to make our roads greener, while maintaining or improving roadway quality.

Transportation and its supporting infrastructure have significant economic, social, and environmental impacts. Using more sustainable methods to design, construct, and preserve roads will better protect the environment and meet our ongoing needs. Mn/DOT and our partners in government, industry, and academia have been researching and implementing ways to make our roads greener, while maintaining or improving roadway quality. MnROAD is conducting research on several “green” pavement technologies that reduce environmental impacts, reuse roadway materials, or use recycled materials in pavement applications:

Minnesota has declared ambitious climate goals aimed at significantly reducing greenhouse gas emissions over the next thirty years, which it plans to accomplish partly through considerable reductions in the average vehicle miles traveled (VMT) per person. This will require close collaboration between local governments and the Minnesota Department of Transportation (MnDOT). This report presents the findings of a brief field scan conducted in early 2023 to understand relevant initiatives, opportunities, and challenges experienced by local communities throughout Minnesota. It involved a review of local plans and documents, a survey distributed among local agencies across the state, and targeted follow-up interviews. Results indicate that while many local organizations have expressed an interest in cutting greenhouse gas emissions, few focus explicitly on transportation emissions and even fewer of those see VMT reduction as a major strategy for meeting those goals. Nonetheless, there are organizations that are interested in the types of policies and investments that could reduce overall driving and help meet ambitious climate goals, often because they support local economic goals. This presents opportunities to realign VMT-reduction strategies with local needs and for MnDOT to provide local support in the form of funding, technical assistance, data resources, and additional guidance.

This report describes the results of a project to develop an on-board emissions and performance measurement system (OEPMS) for the quantification of carbon monoxide (CO) emissions. Researchers measured emissions from a 1990, 2.5 liter TBI engine passenger automobile over a typical suburb-to-city commute in the Minneapolis/St. Paul metropolitan area. As a test of the OEPMS, researchers measured CO emissions during cold weather cold starts and commutes at temperatures characteristic of the area's winter weather. Open-loop and closed-loop emissions of CO were measured and compared. Additionally, the effectiveness of magnetic-type block heaters was examined. Tests with the OEPMS provided a wide range of results. The OEPMS proved very durable and easily adaptable for a wide variety of testing. The OEPMS holds promise for future research into fuels, emissions reducing technologies, regulations, and commute habits in real world situations.

In this project, researchers studied mycorrhizal and vegetational characteristics at prairie and wetland restoration areas. Study objectives included the following: * quantifying the effect of fungal inoculum on plant communities at a Minnesota Department of Transportation (Mn/DOT) prairie restoration site near Cambridge, Minn. * evaluating the prairie forb germination rates * monitoring revegetation at prairie and wetland restoration sites * characterizing mycorrhizal status of native wetland and prairie areas for comparison to the restored sites * producing fungal inoculum for incorporation into further reclamation areas. Findings indicated that 15 months after planting, fungal inoculation resulted in significantly greater cover by native plant species than seen in control plots. At this site, mycorrhizal inoculation benefited the prairie restoration effort by encouraging earlier, more extensive establishment of the planted species. Ongoing studies at this site will determine the long-term effects of mycorrhizal inoculation on the plant community. The report also presents specific recommendations for future restoration efforts. The studies of mycorrhizae in native prairies and wetlands provide further data for a baseline against which to compare restored areas. In addition, fungal inoculum produced in this project has been incorporated into restoration plots at another Mn/DOT site.

Environmental justice is concerned with a variety of public policy efforts to ensure that adverse human health or environmental effects of governmental activities do not fall disproportionately upon minority populations and low‐income populations. In the realm of transportation, environmental justice means that transportation system changes such as road improvements are studied carefully to determine the nature, extent, and incidence of probable impacts, both favorable and adverse. The objective of this project has been to develop a series of practical indicators of economic, social, and environmental impacts related to transportation system changes. Comparing the spatial incidence of these impacts with the locations of low‐income populations and minority populations, it is possible to assess whether the impacts would adversely and disproportionately affect these populations. Our intent is to help make it possible for everyone who is likely to be affected by a particular transportation system change to understand the expected types and magnitudes of anticipated impacts. The objective of such an understanding is to enable those who would be affected to determine which impacts would be most important to them.

As the cost of transporting people increases, questions about paying for the accompanying air and noise pollution increase. This report investigates the distribution impacts of environmental pricing policies on groups in the Twin Cities. The study uses data on travel behavior in the Twin Cities to examine the distributional impacts of three types of environmental pricing policies: a $.65 optimal downtown, peak period congestion fee; a 10 percent gasoline tax; and a 50 percent transit fare reduction. It evaluates each policy in terms of aggregate welfare costs, revenues, emissions reductions, and cost-effectiveness and looks at distributional impacts by using four groupings--income, region, gender, and age. The study found that the congestion fee and gasoline tax are regressive, with the burdens of these taxes increasing with income and decreasing as shares of income. The transit subsidy, on the other hand, disproportionately benefits low-income individuals. Other findings show the advantages and disadvantages to urban and suburban commuters and noncommuters and senior citizens.

This Technical Summary pertains to the LRRB-produced report 2017-50, Study of De-icing Salt Accumulation and Transport Through a Watershed, published December 2017.

This Technical Summary pertains to the LRRB-produced Report 2017-31, “Best Management Practices for Establishment of Salt-Tolerant Grasses on Roadsides,” published July 2017.

This Implementation Summary pertains to report 2019-40, MnDOT Guidance Manual for Potentially Acid-Generating Materials in Northern Minnesota.