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The Twin Cities freeway network is a densely instrumented and growing transportation system. As the Minnesota Department of Transportation (MnDOT) pursues a performance-based management strategy to monitor the health of the network and make planning and management decisions, the data from this vast network is being examined using a variety of methods. To provide MnDOT with timely performance information regarding the Twin Cities freeway network, a streamlined program was developed based on existing and new methodologies. The Highway Automated Reporting Tool (HART) utilizes a user-friendly interface for corridor, date, time, and report selection. Selected data are automatically examined to identify and correct errors and produce 'cleaned' data for use within each report. Using interpolation and autoregressive integrated moving average (ARIMA) techniques, small errors are corrected in place while preserving as much useful data as possible. Larger issues are corrected using an imputation algorithm relies on uses nearby sensors and historical data to create representative replacement data. In this first version of HART, four reports are included: Speed-Based Congestion, Congestion Intensity, Lost and Available Capacity, and Maximum and Total Throughput. The Speed-Based Congestion report matches the existing methodology used to generate the annual Congestion Report.

Active Traffic Management (ATM) strategies are being deployed in major cities worldwide to deal with pervasive system congestion and safety concerns. While such strategies include a diverse array of components, in the Twin Cities metropolitan area the deployment of the Intelligent Lane Control Signs (ILCS) allowed for the implementation of Variable Speed Limits (VSL). The VSL system in the Twin Cities aims to detect congestion and preemptively warn upstream drivers to reduce speed. By reducing the severe change in speed between upstream and downstream traffic, safety and operational benefits are sought. This report presents an investigation of the effect the I-94 VSL system has on the safety of the high frequency crash area located on the westbound lanes of the freeway through downtown Minneapolis (I-94/I-35W commons). This report describes several methodologies that were used to examine the impact of the VSL system within the I-94/I-35W commons high crash area. Numerous data sources were utilized, including video records of crash and near crash events, loop detector traffic measurements, machine vision sensor data, and actuations from the VSL system. A before-after approach was taken to examine the incident rates for crashes and near crashes using visually identified events within video data. Utilizing the unique capabilities of the Minnesota Traffic Observatory's I-94 Freeway Lab, high resolution traffic measurements, collected by machine vision sensors at the bottleneck location, were used within a new cross-correlation based analysis methodology to measure and visualize shockwave activity before and after the implementation of the VSL system.

Dynamically priced High Occupancy Toll (HOT) lanes have been recently added to the traffic operations arsenal in an attempt to preserve infrastructure investment in the future by maintaining a control on demand. This study focuses on the operational and design features of HOT lanes. HOT lanes' mobility and safety are contingent on the design of zones ("gates") that drivers use to merge in or out of the facility. Existing methodologies for the design of access zones are limited to engineering judgment or studies that take into consideration undersized amount of observations. Case in point is the fact that the design philosophes between the two HOT facilities in Minnesota are diametrically opposed. Specifically, the I-394 freeway, the first dynamically priced HOT lane, was designed with a closed access philosophy, meaning that for the greater length of the roadway access to the HOT lane is restricted with only specific short-length sections where access is allowed. In contrast I-35W, the second HOT corridor, was designed with an open access philosophy where lane changes between the HOT and the GPLs are allowed everywhere except for a few specific locations. This contradiction generated questions as to effect each case has on safety and mobility. This study presents an assessment of safety and mobility on the two facilities as they operate today and highlights the issues present on either design.

In the Twin Cities metropolitan area, freeway ramp metering goes back as early as 1969, when the Minnesota Department of Transportation (MnDOT) first tested ramp metering in an I-35E pilot project. To date, the Twin Cities ramp metering system has grown to include more than 433 ramp meters. Research on better, improved ramp control strategies has continued over the years and MnDOT has implemented minor and major changes in the control logic. Two independent studies both aimed at developing the next generation in ramp metering by focusing on density. Based on these efforts, two new algorithms were developed: the UMN Density and the UMD KAdaptive, named based on the campus at which they were developed. The goal of this project was to implement both algorithms and test them under real conditions. Priorities and technical problems prevented the evaluation of the UMN algorithms, so this report focuses on the evaluation of the UMD KAdaptive algorithm on two freeway corridors in the Twin Cities, MN. The first site, a section of TH-100 northbound between 50th Street and I-394, was selected to compare the then current logic, the Stratified Zone algorithm, with the new one. During the course of this project, the UMD algorithm eventually replaced the Stratified Zone algorithm and was implemented in the entire system. This full deployment also included corridors that were not controlled before. The second evaluation site on eastbound TH-212 was a site that allowed for a with/without control evaluation of the UMD algorithm. This report describes the experiments conducted at both sites and includes a comprehensive review of the state of ramp metering strategies around the world to date.

This project investigated the use of Intelligent Lane Control Signs based Active Traffic Management for Incident Management on a heavily traveled urban freeway. The subject of the research was the ILCS system on I-94 westbound in downtown Minneapolis. This location was selected because of the frequency of capacity reducing incidents occurring in this freeway segment. This research aimed to evaluate and quantify the effect the system has on drivers, specifically on inducing/directing a desirable lane selection behavior. The strength of various uses of the tool in managing traffic during incidents is explored instead of a general level of success in improving traffic. To achieve this goal, the centerpiece of this research was the comparison and modeling of the lane change rates under different strategies. This was a difficult task because all lane changes in the target freeway section had to be detected and geolocated. The research followed two main thrusts. The first was a detailed analysis of 28 incident events selected among approximately 481 events on record between 2012 and 2013. The second thrust was a statistical analysis testing a number of hypotheses prompted by questions proposed by the project Technical Advisory Panel. In general, it can be concluded that the use of ILCS for incident management has a significant effect on driver behavior and specifically in prompting proper lane selection under capacity reducing incidents.

Dynamically priced High Occupancy Toll (HOT) lanes have been recently added to the traffic operations arsenal in an attempt to preserve infrastructure investment in the future by maintaining a control on demand. This study focuses on the operational and design features of HOT lanes. HOT lanes' mobility and safety are contingent on the design of zones ("gates") that drivers use to merge in or out of the facility. Existing methodologies for the design of access zones are limited to engineering judgment or studies that take into consideration undersized amount of observations. This project capitalized on the results of an earlier project that performed an assessment of safety and mobility on the HOT facilities in Minnesota highlighted the issues involved in either designs. The product of this project; the MnPASS Access Design application; provides a tool for traffic managers and planners to examine the conditions within an existing or prospective corridor and the distribution of shockwave lengths which are expected. From the distribution of shockwave lengths; decisions can be made regarding access restriction on the HOT lane to ensure that drivers do not attempt to make lane changes at locations prone to dangerous conditions. This tool provides support for the managers and planners by aggregating the entire behavior of the HOT lane within the corridor into a framework for simplified consideration.