Hourdos, John

Studies by the Federal Highway Administration show that American Indians have higher rates of pedestrian injury and death per capita than any other population group in the United States. The Minnesota Department of Transportation (MnDOT) has identified Native Americans as one of six priority populations in Minnesota that face disproportionate risks as pedestrians. This report summarizes efforts taken between 2016 and 2024 to document and reduce risks to pedestrians on the seven recognized Anishinaabe reservations in Minnesota. Across reservations, researchers monitored pedestrian crossings using video recorders at 23 different sites identified by Tribal transportation managers, including 10 Phase 1 sites (2016-2020) and 13 Phase 2 sites (2019-2024). Monitoring results, including pedestrian counts, interactions with drivers, and yield rates, were used to inform planning and implementation of countermeasures to reduce crash risk at six Phase 1 sites and two Phase 2 sites. These countermeasures included marked crosswalks with pedestrian landing pads, better lighting and signage; ADA-accessible pedestrian access ramps; and a pedestrian hybrid beacon. Additional countermeasures have been scheduled or planned for 2024 or later at six more locations. Post-implementation monitoring at six Phase 1 sites confirmed that countermeasures change pedestrian and driver behaviors, but not all pedestrians or drivers use countermeasures as designed. Implementation of countermeasures may change risk factors and reduce risks, but risks cannot be eliminated and will remain after countermeasures are implemented. Consultation, coordination, and cooperation among Tribal, state, and local transportation planners and engineers are essential to reducing crash risk and increasing pedestrian safety.

This research evaluates the performance of non-intrusive detection technologies (NITs) for traffic signals in Minnesota. Prior work shows that while no single NIT device performs best in all situations, under specific circumstances, some NIT devices consistently outperform others. Our goal in this research is to find which NIT devices perform better in conditions specific to Minnesota and provide cost estimations and maintenance recommendations for operating these devices year-round. Our research has two main components: 1)synthesizing national and local experiences procuring, deploying, and maintaining NITs, and 2) evaluating real-world NIT deployments in Minnesota across different weather conditions. Our results and analysis combine the results from these steps to make recommendations informed by research and real-world experience operating NIT devices. Through interviews with Minnesota traffic signal operators, the research finds that environmental factors like wind, snow, and rain cause most NIT failures, requiring costly on-site maintenance. Operators emphasize the need for central monitoring systems, sun shields, and heated lenses to maintain performance. The research then analyzes NIT video, signal actuation, and weather data at six Twin Cities intersections using Iteris and Autoscope Vision technologies. No single NIT performs best, aligning with previous findings, but Autoscope Vision is less prone to lens blockages requiring on-site service. Our analysis also finds some intersections have more failures, indicating location and geometry impact performance. Key recommendations are based on the relative performance of a NIT in different weather conditions and accounting for local weather conditions when selecting a NIT at an intersection. We also recommend using central monitoring systems to troubleshoot remotely, installing heat shields to prevent snow/rain accumulation, and routine annual checks and checks after major storms.

This study evaluates the first and a second implementations of the MN-QWARN queue warning algorithm developed by Hourdos et al. (1). This algorithm was developed to detect specific crash prone conditions created by traffic oscillations (shockwaves) on freeway systems. The MN-QWARN system was specifically calibrated for the freeway studied in Hourdos et al. (1) and was moved to a new location with minimal calibration. This evaluation found that the right-side model had a detection rate of 25% and a false alarm rate of 36%. The left-side model had a detection rate of 64% and a false alarm rate of 23%. We also note high over-warning rates on both lanes. Based on these findings, we recommend recalibrating the MN-QWARN algorithm at this location to examine improvements in performance.

A 4-3 conversion involves changing a four-lane undivided road into one with two general travel lanes separated by a two-way left turn lane. A commonly-used guideline states that a 4-3 conversion can be considering as long as the road’s average annual daily traffic (AADT) volume does not exceed 15,000 vehicles/day but opinions vary, from lowering the AADT threshold to 10,000 vehicles/day to anecdotal evidence for successful 4-3 conversions with AADTs as high as 20,000. The main objective of this project was to identify conditions where 4-3 conversions might be feasible at AADTs greater than 15,000. After reviewing the literature, we conducted simulation studies on three different roads to identify combinations of major and minor road flow where three-lane configurations provided acceptable levels of service. Eight intersections, with 16 approaches, were then selected to represent our findings. These results were presented as summary tables that practitioners could use to make initial assessments regarding 4-3 conversion feasibility.

These tool instructions appear as chapter 5 in report 2015-27, Development of Guidelines for Permitted Left-Turn Phasing Using Flashing Yellow Arrows. The instructions pertain to an Excel macro file that may be accessed from https://edocs-public.dot.state.mn.us/edocs_public/DMResultSet/download?docId=29248594

Appendix E (FULL EXAMPLE OF ICI FROM DIVERGING DIAMOND INTERCHANGE AT HENNEPIN COUNTY ROAD 144 AND TH-101 IN ROGERS, MN) was published separately from report 2019-14, Evaluation of a Central Traffic Signal System and Best Practices for Implementation.

This is a summary of Report 2003-06 "The Employment of the Traffic Management Laboratory (TRAMLAB) for Evaluating Ramp Control Strategies in the Twin Cities."

Separated bicycle lanes (SBLs) are bicycle facilities that employ both paint and a vertical element as a buffer between vehicle traffic and bicycle traffic. In recent years, the installation of SBLs has increased in the U.S. as planners and engineers seek to reduce crash risk, increase safety and foster demand. In turn, public demand for these facilities has continued to grow. This project conducted a thorough literature search to identify knowledge gaps and aspects of design not addressed in depth in existing guides. In collaboration with the Local Road Research Board and MnDOT, the study identified which design elements were of the greatest local interest or missing from the guidance altogether. The identified subject areas were explored with the help of three major knowledge gathering approaches: interviews of industry professionals from local agencies currently operating SBLs, interviews with leading bicycle advocates representing the local cycling community, and an ambitious and lengthy online survey of people who cycle in Minnesota. As noted by several existing guidance documents and corroborated by the information collected and analyzed in this project, the SBL is one of the highest quality bikeway facilities available. This report adds to the existing guidance regarding the planning and operation of SBLs by refining the discussion and taking into account individual aspects of separate design elements and their implementation alternatives, as well as their influence and limitations on maintenance needs, especially in winter. The guidance identifies multiple considerations for each of the selected structural elements and maintenance considerations to inform the choices made during the design process.

Basic Safety Message (BSM) containing data about the vehicle's position, speed, and acceleration. Roadside receivers, RSUs, can capture BSM broadcasts and translate them into information about traffic conditions. If every vehicle is equipped with awareness, BSMs can be combined to calculate traffic flows, speeds, and densities. These three key parameters will be post-processed to obtain queue lengths and travel time estimates. The project team proposed a traffic state estimation algorithm using BSMs based on the Kalman filter technique. The algorithm's performance was tested with BSMs generated from several arterial in a microscopic simulation model and BSMs generated with radar data collected on freeway sections. Then the project team developed a traffic monitoring system to apply the algorithm to a large-scale network with different types of roads. In the system, computers could remotely access the online server to acquire BSMs and estimate traffic states in real-time.

The Minnesota Department of Transportation (MnDOT) has identified Native American as one of six priority populations in the state that face disproportionate risks as pedestrians. This report summarizes results from observations of pedestrian crossing behaviors on four Anishinaabe reservations in northern Minnesota. The University of Minnesota Traffic Observatory (MTO) video-taped and classified pedestrian crossings at 10 intersections identified by Tribal transportation managers as high priority because of perceived risks. Across the intersections; pedestrian crossing volumes during daylight hours ranged from 3 per day to 136 per day. The percent of pedestrian crossings that involved interactions with vehicles ranged from 9% to 54%. Tribal transportation managers from the Bois Forte; Fond du Lac; Grand Portage; and Mille Lacs Bands; MnDOT; county engineers; and the investigators collaborated to identify countermeasures to address risks to pedestrians. Proposed countermeasures varied by intersection and included vegetation removal and line-of-sight improvements; new lighting; crosswalk improvements; Rectangular Rapid Flashing Beacons with advanced warning signs; ADA-compliant ramps; pedestrian education programs; realignment of intersections; and at one intersection a Pedestrian Hybrid Beacon. Prospects for implementation of countermeasures vary by intersection and reservation and are contingent on Tribal and transportation agency budgets; state and county plans for roadway improvements; and categorical grant programs such as Minnesota's Transportation Alternatives Program. Some countermeasures are being implemented; and MnDOT is extending the approach to additional reservations.