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MnDOT has already deployed an extensive infrastructure for Active Traffic Management (ATM) on I-35W and I-94 with plans to expand on other segments of the Twin Cities freeway network. The ATM system includes intelligent lane control signals (ILCS) spaced every half mile over every lane to warn motorists of incidents or hazards on the roadway ahead. This project developed two separate systems that can identify lane-specific shockwave or queuing conditions on the freeway and use existing ILCS to warn motorists upstream for rear-end collision prevention. The two systems were field tested at two locations in the ATM equipped network that have a high frequency of rear-end collisions. These locations experience significantly different traffic-flow conditions; allowing for the development and testing of twodifferent approaches to the same problem. The I-94 westbound segment in downtown Minneapolis is known for its high crash rate due torapidly evolving shockwaves while the I-35W southbound segment north of the TH-62 interchange experiences longstanding queues extending into the freeway mainline. The Minnesota Traffic Observatory developed the I-94 Queue Warning system while the University of Michigan; under contract; developed the I-35W system. Prior to the I-94 installation; based on data collected in 2013; there were 11.9 crashes per VMT and 111.8 near crashes per VMT. In the first three months of the system's deployment; event frequency reduced to 9.34 crashes per million vehicle miles of travel (MVMT) and 51.8 near crashes per MVMT; a 22% decrease in crashes and a 54% decrease in nearcrashes. The I-35W system did not undergo a similarly thorough evaluation; but for most of the lane segments involved; it showed that queue warning messages help reduce the speed variance near the queue locations and the speed difference between upstream and downstream locations. This also implicated a satisfactory level of compliance rate from travelers.

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.

The Smart Work Zone Speed Notification (SWZSN) system aims to alleviate congestion; queuing; and rear end crashes in work zones by informing drivers of the speed of the downstream segment using a type of portable Intelligent Lane Control System (ILCS); Portable Changeable Message Signs (PCMS). The hypothesis was that drivers; knowing the speed up to 1 mile downstream; will slow down early or at least be alert and perform smoother decelerations. Video of the SWZSN was analyzed over two years of operation by the Minnesota Traffic Observatory. Overall; the system resulted in beneficial reductions of selected decelerations by the drivers. In situations where the messages communicated to the drivers were consistent and accurate; reductions of more than 30% in the selected deceleration rates were observed. Unfortunately; there were several cases where counterproductive or misleading messages were communicated to the drivers; prompting relative increases to the selected deceleration rates. The most important observation; stemming from both positive and negative influences; was that the speed notification system was noticed by drivers and resulted in a statistically significant influence on driving behavior; unlike other driver alert systems.

In response to the limited awareness surrounding Bus Rapid Transit (BRT) and the A Line; this study provides answers to questions regarding the operation and public perception of the A Line in the Twin Cities region; Minnesota. Two traffic scenarios were studied; one for high-volume oversaturated traffic during the Minnesota State Fair; and a second for normal operating conditions. For both scenarios; intersection queue length and traffic flow rate were compared before and after an A Line bus. It was found that in both time periods (Fair and non- Fair); the dwelling of an A Line bus during a green traffic signal did not have a statistically significant impact on intersection queue length or traffic-flow rate at either of the two researched stations. From an analysis of the 2016 On-Board Survey; it was determined that passengers are more satisfied by the overall service of the A Line than local buses while there is not a significant difference in overall satisfaction compared to express buses; light rail and commuter rail. The top three important service attributes to overall satisfaction are "paying my fare is easy;" "hours of operation;" and "handling of concerns/complaints." It is recommended that the transit agency improve the attributes that have higher relative influences and lower mean performances. Based on this criterion; the attributes that should be given priority are "shelter/station conditions and cleanliness" and "behaviors of other passengers and atmosphere on board." This is report #16 in the Transitway Impacts Research Program series.

Pedestrian-Activated Crossing (PAC) systems have been shown to have a generally positive impact on driver yield rates. However; there has been insufficient research on the effect PAC treatments have on pedestrian crash rates; and there is little guidance as to when and where each treatment should be used. This study estimates the effects of PACs on pedestrian crash rates using Monte Carlo simulation and examines the relationships between driver yield rates and a variety of treatments and site designs by conducting an observational study using video data from 34 locations. The simulation outcomes suggests that while the percentage of yielding drivers might be a useful indicator of pedestrian level of service; it is less helpful as safety surrogate. This could be because a driver's yielding to a pedestrian; as observed in field studies; might not be the same behavior as a driver attempting to stop during a vehicle/pedestrian conflict. The observational study shows that the number of lanes to cross at a crossing is positively correlated with the rate at which pedestrians activate the system; but it is not correlated with the delay. Additionally; the study showed that the effect of PAC systems is most pronounced at sites with a higher number of movements conflicting with the crossing or poor visibility from upstream without signs warning drivers of an upcoming crosswalk.

Stop lines are ubiquitous; but do they really impact intersection safety? Prior to this project; no long-term studies on intersection safety with stop lines had been completed. This project was developed with two parallel research efforts: a safety study and an observational study. The safety study was developed to address stop lines' effects over the long term and used crash data from five cities' stop-controlled intersections to perform regression and see if stop lines actually influenced safety. The observational study was developed to determine if stop lines have an effect on driver behavior at intersections and to look at where drivers were stopping. Video was collected at 16 different intersections before and after a stop line was painted. The safety study and observational study showed that stop lines did not have a significant impact on driver behavior or intersection safety; but other factors like speed limits and sight distance did. Implications for practice include carefully examining sight distance at the intended stopping point to ensure drivers have adequate sight distance in both directions. If sight distance is not adequate; moving the intended stop location or reconsidering whether the intersection should have signage -- stop or yield -- or be uncontrolled could yield better driver compliance and safety.

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.

This study evaluates recent technology that uses inductive loop detectors, traditionally used for collecting traffic volume and speed data, to provide vehicle classification data by examining the high-resolution signature produced when a vehicle passes over the sensor. The project aims to verify the accuracy of the new classification system, collect additional heavy vehicle data to help improve system accuracy, and familiarize MnDOT staff with the technology through training and the development of a field deployment manual. Through collaboration with MnDOT and the technology vendor CLR Analytics, Inc., the VSign vehicle classification system has been installed at five sites in Minnesota with preexisting loop detection systems. The final sites are representative of MnDOT facilities, feature a mix of heavy vehicle traffic, and provide accessibility for deployment staff. Data from the VSign system was compared with manually verified ground-truth data collected from video under both the Federal Highway Administration (FHWA) and Highway Performance Monitoring System (HPMS) classification schemes. The system demonstrated high accuracy for passenger vehicles but varying accuracy for different classes of heavy vehicles, though performance improved under the HPMS classification scheme. The VSign system was also evaluated against the video-based iTHEIA™ system at one site, which VSign outperformed in both classification accuracy and detection rate. The results suggested that the VSign system was more effective at locations where vehicles maintained consistent speeds and were centered in the lane due to the negative effects of variations in speed and lateral position on the consistency of vehicle signatures read by the detector.