Levinson, David M.

Improvements to transportation networks, especially those in growing areas, tend to have impacts on local land markets. In principle, an improvement to a link in the network will confer economic benefits to adjacent and nearby properties by increasing the utility that the network provides. Traditional methods of economic analysis for highway improvement projects have focused primarily on user benefits and sought to quantify them through the estimation of reductions in travel delay or user cost. However, urban economic theory suggests that many of these benefits are capitalized into local property values, yielding a localized spillover effect. Accordingly, it should be possible to develop rough estimates of the value of the benefits from a highway project by estimating the response of local land markets to the improvement. This report explores the nature and magnitude of benefits accruing to nearby properties that arise from major highway construction or reconstruction projects, more precisely those that add capacity to an existing highway. Highway projects in three Minnesota counties (Hennepin, Jackson, and Olmsted) form the basis for our analysis.

This research evaluates the accuracy of demand forecasts using a sample of recently-completed projects in Minnesota and identifies the factors influencing the inaccuracy in forecasts. The forecast traffic data for this study is drawn from Environmental Impact Statements (EIS), Transportation Analysis Reports (TAR) and other forecast reports produced by the Minnesota Department of Transportation (Mn/DOT) with a horizon forecast year of 2010 or earlier. The actual traffic data is compiled from the database of traffic counts maintained by the Office of Transportation Data and Analysis at Mn/DOT. Based on recent research on forecast accuracy, the inaccuracy of traffic forecasts is estimated as a ratio of the forecast traffic to the actual traffic. The estimation of forecast inaccuracy also involves a comparison of the socioeconomic and demographic assumptions, the assumed networks to the actual in-place networks and other travel behavior assumptions that went into generating the traffic forecasts against actual conditions. The analysis indicates a general trend of underestimation in roadway traffic forecasts with factors such as highway type, functional classification, and direction playing an influencing role. Roadways with higher volumes and higher functional classifications such as freeways are subject to underestimation compared to lower volume roadways/functional classifications. The comparison of demographic forecasts shows a trend of overestimation while the comparison of travel behavior characteristics indicates a lack of incorporation of fundamental shifts and societal changes.

Report #7 In The Series: Access to Destinations Study. This study presents an effort to track and model land use change in the Twin Cities Metropolitan Region. To that end, we make use of a unique, high-resolution, cell-level set of land use data for the Twin Cities. The data represent 75 meter by 75 meter land use cells, observed at several points in time during the period from 1958 to 2005. These data are used to validate three different types of land use models, which then are used to forecast land use several decades into the future. The models applied in this study include Markov Chain models, Markov Chain- Cellular Automata (MC-CA) models, and an empirical model based on a logistic regression specification. The models are intended to have a simple, transparent structure that allows the user to identify sources of forecast error. Forecasts of land use are made both for the entire study area and also for a specific corridor along State Highway 610 in the northwestern suburbs of the Twin Cities. The study concludes with a brief discussion of the limitations of the models, and how they might meaningfully be expanded and applied.

Report #5 in the series: Developing Intersection Decision Support Solutions. The Intersection Decision Support (IDS) system is designed to assist drivers on stop-controlled low-volume rural roads choosing gaps when confronted with busy multiple lane divided-highways, without affecting traffic on the high-volume road. The hope is, that by providing better gap guidance, fewer crashes (and fatalities) will occur. This research develops a framework for analyzing such a new, and presently under-specified technology, and illustrates that framework by comparing that with more conventional engineering approaches, as well as a "do nothing" base case. The results show that the IDS System may be an effective tool to reduce crash rates at various intersections. More research is needed to address reliability and stability issues, and in determining how cost effective of a solution the IDS System is compared to other "traditional" alternatives.

This research, extending the Mn/DOT-funded project If They Come, Will You Build It, assesses the implications of existing trends on future network construction. It compares forecast networks (using models estimated on historical decisions developed with previous research) under alternative budget scenarios (trend, above trend, below trend), with networks constructed according to alternative sets of decision rules developed with Mn/DOT and Metropolitan Council staff. The comparison evaluates alternative futures using a set of performance measures to determine whether the network we would get in the absence of a change in policies (allowing historical policies to go forward) outperforms or underperforms the networks developed by applying suggested decision rules. This evaluation methodology enables new decision rules for network construction (building new links or widening existing links) to be tested. The research suggests a path beyond "business as usual."

Transportation systems are designed to help people participate in activities distributed over space and time. Accessibility indicates the collective performance of land use and transportation systems and determines how well that complex system serves its residents. This research project comprises three main tasks. The first task reviews the literature on accessibility and its performance measures with an emphasis on measures that planners and decision makers can understand and replicate. The second task identifies the appropriate measures of accessibility, where accessibility measures are evaluated in terms of ease of understanding, accuracy and complexity, while the third task illustrates these accessibility measures. During this process a new accessibility measure named "Place Rank" is introduced as an accurate measure of accessibility. In addition, several previously-defined accessibility measures are reviewed and demonstrated in this report including Cumulative opportunity and gravity-based measures. The gravity-based measure is widely used in the literature yet cumulative opportunity tends to be easier to understand and interpret by the public, planners, and administrators. A major contribution of this research is the comparison of accessibility measures over time and among various modes. Effects of accessibility on home sales are also tested. Homebuyers pay a premium to live near jobs and away from competing workers. Accessibility promises to be a useful tool for monitoring the land use and transportation system, and assessing and valuing the benefits of proposed changes to either land use or networks.

Drivers receive value from traveler information in several ways, including the ability to save time, but perhaps more importantly, from certainty, which has other personal, social, safety, or psychological impacts. This project aims to quantify travelers' willingness to pay for pre-trip travel-time information on alternative routes. Different from previous studies based only on stated preference surveys, the 117 participants in the current study actually drove real-world routes. Pre-trip travel-time information was provided in the field experiment to half the participants. Various data collection techniques were used including in-vehicle GPS units, pre- and post-experiment surveys, and travel diary. Results reveal that speed and efficiency are not the only dimensions on which people make route choices. Ease of driving, pleasantness, and the presence of information are also significant factors. Results from multinomial and rank-ordered logit models indicate that many travelers receive value of up to $1 per trip for pre-trip travel-time information. The value of this information is higher for commuting, special event trips, and when there is heavy congestion. The accuracy of the travel-time information is crucial - it is only useful if it is believed to be accurate.

Across the state of Minnesota, asphalt roads under the jurisdiction of counties, cities and townships have been controlled by restrictions that limit the total weight of each truck that uses those roads during the spring thaw period. During this time, the pavement weakens and the bearing capacity of the roadway is reduced. These policies vary from county to county and from road to road, depending on the capacity of the roads - typically, 5, 7 and 9 tons. While spring load restrictions serve to extend the useful life of the road, they also add significant burdens to truckers who are forced to re-route their vehicles and/or increase the number of trips in order to adhere to the policies. This study assesses the economic impact of lifting all vehicle restrictions during the spring thaw period. Economic benefits of lifting the bans include reduced cost to carriers; potential cost includes reduced pavement life. Their research concludes that if the policy is changed, the costs of additional damage could be recovered from those who use the roads. Recovering those costs could take the form of annual fees, appropriate fuel taxes and/or user charges paid by vehicle operators.

Traffic congestion has become an increasingly serious problem in many cities. Ramp metering, which maintains smooth freeway mainline flow by limiting vehicle entry at entrance ramps, has been proposed and implemented in a number of metropolitan areas in and outside the U.S. to mitigate freeway congestion. This study aims to develop both efficient and equitable freeway ramp control strategies. Traffic conditions with and without ramp metering are evaluated on several representative freeways in the Twin Cities with a comprehensive set of performance measures. A unified theory for ramp metering is proposed based on a linear programming model of freeway traffic dynamics. The most efficient ramp control algorithm is found to be also the least equitable one. A novel control objective, minimizing weighted or perceived travel time, is therefore proposed to balance efficiency and equity objectives of ramp metering. This research also develops a new family of applicable ramp metering strategies, which consider both efficiency and equity, and are demonstrated in a microscopic traffic simulator. Future studies should compare various traffic control methods under the analytical framework proposed in this report. Researchers should also pursue field experiments of the proposed multi-objective ramp control strategies.

This report develops several models of historical roadway improvements in the Twin Cities metro area. Planners respond to, and try to shape, demand by recommending investments in new infrastructure and changes in public policy. Sometimes capacity is added to existing facilities. Other times, building new roads is the response. As a result of this research, the ways in which current network expansion or contraction decisions alter the choices of future decisionmakers has become clearer. This research develops a theoretical framework, constructs a comprehensive time series database describing network investment, utilization and capacity, estimates several statistical models, and interprets the results to guide planning.