The impacts of climate change on the Department of Transportation (MnDOT) are significant. MnDOT is committed to addressing climate change adaptation in our statewide vision: that Minnesota’s multimodal transportation system, “is flexible and nimble enough to adapt to changes in society, technology, the environment and the economy.” Climate issues will affect many functional groups within MnDOT, including Bridge Hydraulics, Water Resources, Maintenance, Design, Construction, Materials, and Freight, Rail and Waterways.
Climate change is already having major impacts in Minnesota and change is likely to occur in a number of key areas. These changes can have negative effects on the state’s transportation system. However, changes in certain areas are more likely to occur than in others. For example, Minnesota has already seen increased heavy precipitation / flooding in recent years. It is very likely that this trend will continue into the future.
|Climate Impact||Confidence in change for MN during next 20 years||Potential Negative Effects to Transportation System|
|Heavy Precipitation / Flooding||Very High||
Damage to highway, rail infrastructure, hydraulics infrastructure, airport runways
Overtopping roads will slow operations and performance.
|Warmer Winters||Very High||
More ice build-up and freezing precipitation
Reduced pavement conditions and life cycles
Downed power lines with ice storms
Reduced ice cover on water bodies leading to greater rates of evaporation
|New species ranges||High||
Changes in roadside vegetation mixes
Increase in invasive species populations
Increased exposure of construction and maintenance crews to vector-borne diseases
Reduced river navigability for barges
Stress roadside vegetation, which may reduce rainwater storage and increase soil erosion in the long-term
Pavement and rail buckling
Electrical system malfunctions
Limitations on construction hours
Immediate and significant threat to human safety
Damage to roadside infrastructure
The predictions for increased frequency and intensity of rainfall events, extreme heat events resulting in decreased air quality, and an increased number of freeze/thaw cycles will affect the way MnDOT designs, builds and maintains the state’s multi-modal transportation infrastructure. It will also compel MnDOT to inventory all transportation assets, assess which ones are most vulnerable to the impacts of climate change and determine a cost-effective method to mitigate and minimize those impacts. Emergency preparedness plans will be updated to reflect those lessons learned as a result of recent flash flooding events.
MnDOT is responding to climate change impacts in a number of areas:
Secured funding in 2013 from the Federal Highway Administration and internally to conduct a climate vulnerability assessment pilot project in two of MnDOT’s flood prone areas to better understand extreme weather impacts to the transportation assets and identify cost-effective options to make the transportation system more resilient to extreme weather-related flooding.
$50 million of Chapter 152 bonds were dedicated to fund projects that mitigate and ensure long-term sustainability for flood prone highways. All projects must be constructed by fiscal year 2016.
Bridge Scour Related Efforts
Scour may leave bridges vulnerable to damage and failure during flooding by undermining bridge foundations or removing the protection from the abutment slopes. MnDOT is addressing bridge scour through efforts including: managing a webpage that provides bridge scour monitoring information. A Bridge Scour Plan of Action for all 30 bridges that are scour critical or need to be monitored for scour was developed in addition to a Bridge Office Flood Response Plan. Finally, a cooperative agreement was set up with the U.S. Geological Survey (USGS) that allows MnDOT to hire them to monitor bridges during floods.
Support up-to-date Hydrology
While this is not predictive for future changes, MnDOT is participating in keeping precipitation frequency estimates and discharge regression equations up to date. This included developing a cooperative agreement with the USGS where MnDOT provides funding to maintain crest gages to collect data that is used to develop stream regression equations, develop new regression equations every 10 years, develop and maintain Streamstats, and perform hydrologic studies. MnDOT also works to update precipitation frequency data, and provided funding to NOAA to help develop Atlas 14, as well as created an outreach webpage on the implementation of Atlas 14. NOAA Atlas 14 is an important new data source that fully documents the changing frequency of extreme precipitation in Minnesota, updating previous precipitation frequencies which in some cases are decades old.
Funding for Research Projects
Provide funding for research projects, including ditch or swale infiltration to reduce runoff, roadway overtopping protection, scour monitoring implementation, drought tolerant sod, and natural flocculants to reduce total suspended solids and phosphorous discharge during extreme weather events that occur during project construction.
Other MnDOT Climate Adaptation Activities:
- Asset management activities - developing more efficient ways to inventory our transportation assets that may be impacted by extreme climate events.
- Participation in state climate change, climate adaptation and air quality groups to better understand how climate issues directly affect Minnesota and to collaborate with other state agencies on how to minimize the impacts and increase our resilience.
- Participation in national committees facilitated by the Federal Highway Administration, American Association of State Highway and Transportation Officials and the Transportation Research Board to stay informed on transportation-related climate strategies.
- Dedicated funding for MnDOT's Flood Mitigation Program.
- Partnered with the DNR and BWSR to develop flood and drought tolerant seed mixtures that are being implemented on our roadsides and stormwater pond facilities.
- Implemented Context Sensitive Solutions and Complete Streets in project planning and design, leading to preserving and enhancing scenic aesthetic, historic, community, and environmental resources, while improving or maintaining safety, mobility, low impact development, and infrastructure conditions.