Case Study Highlights
- Utilizes overall safety performance measures and sub measures specific to safety issues, modes, etc.
- Provides uniform, performance-based process to identify safety investments.
- Identifies specific countermeasures needed to target most frequent crash types.
The Minnesota Department of Transportation (MnDOT) uses safety-related planning performance measures to identify investment needs. District-Level Investment Plans identify priorities based on projected revenue and investments needed to adhere to policies and meet performance goals as outlined in the Statewide Transportation Plan.
Minnesota's Statewide Transportation Plan (2009 to 2028) focuses on 10 policies, one of which is Traveler Safety. The numbers of fatalities and serious injuries for all travel modes are identified as the highest level safety performance measures. Additional submeasures related to specific modes include, among others, motorcycle, pedestrian, and commercial-related fatalities. MnDOT also tracks the share of fatal and severe or incapacitating injuries on urban and rural roads and dollars spent on Highway Safety Improvement Program (HSIP) Stand Alone Safety Projects to understand how well traveler safety is being addressed. MnDOT developed system performance targets using historical data, customer research, engineering analysis, economic analysis, fiscal trends, and institutional values.
As a part of the statewide transportation plan update, MnDOT districts updated their long-range Highway Investment Plans. These 20-year investment plans provide the link between the policies and strategies established in the Statewide Plan and capital improvements on the State highway system.
MnDOT established a process and guidelines to ensure District Investment Plans were developed in a consistent manner and planned improvements address statewide goals and investment priorities. The development process began with the identification of highway system needs and revenue projections for each of the three planning periods. Investment goals were then used to develop the State Highway Safety Investment Plan. Unfunded needs also are prioritized. A working group of MnDOT and FHWA safety and traffic engineers established treatments, application criteria, and cost estimates for roadway enhancements. Application criteria are used to assess all State highways and identify when and where improvements are needed.
Investments can be broadly characterized as roadway enhancements or capacity improvements. Roadway enhancements emphasize systemwide, cost-effective strategies that target the types of crashes occurring most frequently on rural highways in the State. The most frequent crash types account for nearly 70 percent of the State's fatalities. Typical enhancements may include, but are not limited to, edge treatments, centerline rumble strips, rural intersection enhancements, turn lanes, passing lanes, full shoulders, and cable median barriers. In most cases roadway enhancement improvements are constructed as part of other, larger highway projects. Capacity improvements are intended to reduce or eliminate vehicle conflicts at locations meeting specific traffic volume thresholds. These projects are generally higher-cost strategies and are initiated as stand-alone projects.
Results
MnDOT's performance-based investment plan enables the State to estimate the investments needed to meet established performance measure targets for traveler safety. MnDOT has created a vertically integrated structure ensuring policies made at headquarters are implemented in the districts. A consistent level of investment effort across districts toward achieving statewide system performance targets was accomplished by establishing a consistent process and guidelines for district-level investment plans.