Urban Studies and Planning Commons^™

Locating Truck Data Collection Sites In Oregon Using Representation Optimal Sampling, Kenneth Dueker, William A. Rabiega, Bruce Rex

Center for Urban Studies Publications and Reports

The Oregon Department of Transportation collects data on the performance of the highway system by sampling traffic volume, vehicle classification, truck weights, pavement conditions, etc. The selection of efficient and accurate locations for collecting data is important. This report addresses the larger sampling problem by focusing on locations for collecting truck weight data. Sites selected for weight-in-motion/automatic vehicle identification (WIM/AVI) within the Crescent/HELP project are assessed to determine their locational suitability for truck weight data collection. A method, Representation Optimal Sampling (ROS), to aid in site selection is reported here. Sampling configurations of six and twelve station using ROS are …

Trends In Vacant Single Family Land Values Portland, Oregon 1990 To 2005, John L. Hall, Gerard C. Mildner

Center for Urban Studies Publications and Reports

The purpose of this report is to summarize price trends from 1990 to 2005 in vacant land zoned for single family development in the Portland region. While regional housing prices are compiled, tracked, and reported on a regular basis by sources like the Regional Multiple Listing Service (RMLS), information on trends in vacant land sales remains dispersed among independent builders, county assessors, and appraisers. As a consequence, while current and accurate information exits to inform a discussion about regional and local housing policy, relatively limited information exists on which to base discussions of regional and local land policies.

Effects Of Comprehensive Plan Amendments On Interchange Traffic In Oregon, James G. Strathman, Thomas J. Kimpel, Paul Roland Leistner, Kenneth Dueker

Center for Urban Studies Publications and Reports

In this paper we examine the effects of amendments to local comprehensive plans on interchange performance. Plan amendments over a 15-year period in Oregon resulting in changes to industrial or commercial land use were reviewed to identify those that occurred within one mile of an interchange. Regression analysis was then performed to estimate the impact of nearby plan amendments on subsequent interchange ADT. Plan amendments were found to have a substantial ADT effect on rural interchanges, but their incidence was very limited. In urban core areas, the estimated effect of plan amendments was negligible, possibly due to interchange congestion or …

Analysis Of Transit Signal Priority Using Archived Trimet Bus Dispatch System Data, Thomas J. Kimpel, James G. Strathman, Robert L. Bertini, Steve Callas

Center for Urban Studies Publications and Reports

This paper presents findings on changes in bus running times, on-time performance, and excess passenger wait times following implementation of transit signal priority in select bus corridors in the Portland metropolitan region. Analysis of the effectiveness of transit signal priority is often undertaken using simulation techniques or empirical studies that are either limited in scope and/or data availability. The present research uses an abundance of trip-level data collected from TriMet’s Bus Dispatch System. The study focuses on the most common performance measures of interest to both transit operators and passengers. Our study shows that the expected benefits of TSP are …

Research Note: Determinants Of Bus Dwell Time, Kenneth Dueker, Thomas J. Kimpel, James G. Strathman, Steve Callas

Center for Urban Studies Publications and Reports

This research note reports an analysis of dwell times at bus stops using archived Automatic Vehicle Location/ Automatic Passenger Counter (AVL/APC) data reported at the level of the individual bus stop. The data provide a large number of observations that serve to better understand the determinants of dwells, including analysis of rare events, such as lift operations. The analysis of bus dwell times at bus stops is applicable to TriMet, the transit provider for the Portland metropolitan area, and transit agencies in general. The determinants of dwell time include passenger activity, lift operations and other effects: low floor bus, time …

Headway Deviation Effects On Bus Passenger Loads: Analysis Of Tri-Met’S Archived Avl-Apc Data, James G. Strathman, Thomas J. Kimpel, Steve Callas

Center for Urban Studies Publications and Reports

In this paper we empirically analyze the relationship between transit service headway deviations and passenger loads, using archived data from Tri-Met’s automatic vehicle location and automatic passenger counter systems. The analysis employs two-stage least squares estimation to account for the simultaneous relationship between headway deviations and loads. Controlling for the effects of passenger activity on delay, the results indicate that the observed incidence of excess passenger loads is systematically attributable to deviations from scheduled headways. In turn, analysis of the causes of headway deviations served to identify possible operations control actions that would improve service regularity and, consequently, reduce incidences …

Clackamas County - City Of Milwaukie Urban Services Study: Financial Analysis, Emile H. Combe, Gerard C. Mildner, Charles A. Santo

Center for Urban Studies Publications and Reports

The provision of local government services within the urbanizing area of northwest Clackamas County has posed a difficult challenge for a number of years. This report examines the financial aspects of providing urban services to a study area with the following boundaries: the Clackamas County/Multnomah County line to the north, Interstate 205 to the east, highway 224 to the south, and the City of Milwaukie to the west.

Building And Maintaining A Statewide Transportation Framework, Kenneth Dueker, Paul Bender

Center for Urban Studies Publications and Reports

Creating and maintaining up-to-date sharable Geographic Information SystemsTransportation (GIS-T) data is challenging. Many states are working on Transportation Framework efforts to build a complete, consistent, and current transportation data layer in conjunction with the NSDI and Geospatial One-Stop efforts. This paper summarizes an effort that systematically re-examined transportation data sharing issues as part of the development of a Transportation Framework for the State of Washington. Business needs were assessed in terms of spatial and temporal accuracy needs of stakeholders and users of a state-wide Transportation Framework. A conceptual model was developed for a Transportation Framework with emphasis on data flows …

Mandating Density: The Blunt Instrument Of Smart Growth, Kenneth Dueker

Center for Urban Studies Publications and Reports

This essay expresses concern that urban growth management places too heavy a reliance on densification, particularly upzoning with minimum density requirements in suburban infill situations. Increasing densities may be appropriate when other aspects of urban development can be controlled through urban design. However, evidence provided here indicates that mandating density reduces land consumption, but does not achieve other objectives of growth management, particularly street connectivity, greater use of alternative modes of transportation, and more housing choices. This analysis finds that upzoning and requiring minimum-densities, when used to regulate suburban residential infill developments, is not effective in producing quality compact development. …

Tri-Met's Experience With Automatic Passenger Counter And Automatic Vehicle Location Systems, James G. Strathman

Center for Urban Studies Publications and Reports

The Tri-County Metropolitan Transportation District of Oregon (Tri-Met) is one of about 30 metropolitan transit agencies that have deployed both automatic vehicle location (AVL) and automatic passenger counter (APC) systems (Casey, 1999). These technologies are important components of the agency’s new automated bus dispatching system (BDS). The AVL and APC systems at Tri-Met recover comprehensive operations and passenger activity data at the bus stop level that is archived for later analysis. The agency has gained a reputation as an industry leader in the areas of data archiving and the application of archived data to performance monitoring and analysis.

Prior to …

White Paper On Issues And Strategies For Building A State Transportation Framework, Kenneth Dueker, Paul Bender

Center for Urban Studies Publications and Reports

The purpose of this white paper is to systematically re-examine transportation data sharing issues that have been discussed at length, but in a manner to foster final decisions and closure. In some cases, choices among alternatives may require more detailed analysis or pilot studies. The development of this document has benefited from discussion at the Interorganizational Resource Information Coordinating Council (IRICC) Roads Committee, which has led to this consensus document. This sixth and final version serves to draw the process to a close and recommends a twofold approach to the development of a Transportation Framework. It also recommends six pilot …

Analysis Of Transit Fare Evasion In The Rose Quarter, Shimon Isreal, James G. Strathman

Center for Urban Studies Publications and Reports

Tri-Met collected fare evasion data for buses and MAX trains passing outbound through the Rose Quarter Monday, June 11 through Saturday, July 7. Beginning September 2001, Tri-Met’s “Fareless Square’s” free zone was extended towards the Lloyd District, with an eastern boundary of NE 14th. Prior to this, all trips between the Central Business District and Lloyd Center required a full Zone 1 fare.

Development Of A Statistical Algorithm For The Real-Time Prediction Of Transit Vehicle Arrival Times Under Adverse Conditions, Kenneth Dueker, Thomas J. Kimpel, James G. Strathman

Center for Urban Studies Publications and Reports

Prior TransNow funded research by Portland State University (PSU) and the University of Washington (UW) in cooperation with Tri-Met, the transit provider for the Portland metropolitan area, has utilized a rich set of archived data from the Automatic Vehicle Location (AVL)-based Bus Dispatch System (BDS). Tri-Met is one of the few transit agencies that archive AVL data for analysis and research.

Economics Of Overloading And The Effect Of Weight Enforcement: Research Note, James G. Strathman

Center for Urban Studies Publications and Reports

This note describes the economic rationale for exceeding weight limits by motor carriers in the face of weight enforcement activities. Patterns of weight enforcement practices by states are identified reflecting differences in enforcement intensity and the severity of penalties imposed for exceeding weight limits. Statistical analysis of weight enforcement data shows that the marginal effects of enforcement intensity and penalties are similar in deterring overloading, with most of the enforcement-related deterrence attributable to the use of portable/semi-portable scales.

Analysis Of Design Attributes And Crashes On The Oregon Highway System, James G. Strathman, Kenneth Dueker, Jihong Zhang, Timothy Williams

Center for Urban Studies Publications and Reports

Since the passage of the Highway Safety Act of 1966, state departments of transportation have engaged in systematic safety improvement planning and programming. According to Davis (2000), the general approach to safety improvement planning employed by most states follows six principal steps:

1. Identification of hazardous roadway locations using crash records;

2. Detailed engineering study of selected hazardous locations to identify roadway design problems;

3. Identification of potential countermeasures;

4. Assessment of the costs and benefits of potential countermeasures;

5. Implementation of countermeasures with the highest net benefits;

6. Assessment of countermeasure effectiveness following implementation.

All planning processes are subject …

Evaluation Of Transit Operations: Data Applications Of Tri-Met’S Automated Bus Dispatching System, James G. Strathman, Thomas J. Kimpel, Kenneth Dueker, Rick Gerhart, Steve Callas

Center for Urban Studies Publications and Reports

Over the past decade, the adoption of Advanced Public Transportation System (APTS) technology has been motivated by transit providers’ desire to improve service reliability as well as to identify potential savings from improvements in scheduling and service planning. Casey (2000) reports that Automatic Vehicle Location (AVL) systems, a cornerstone of APTS, have been deployed by 61 transit agencies as of 1998.

Transit Oriented Development: Trip Generation & Mode Split In The Portland Metropolitan Region, Michael Lapham

Center for Urban Studies Publications and Reports

The Portland metropolitan region has planned and implemented transit-oriented developments (T.O.D.) along light rail alignments and traditional transit corridors based on the assumption that promoting mixed-use, high density residential development close to transit will reduce vehicle trips, lessen congestion, and reduce air pollution. Oregon has state and local transportation policies that rely on alternative modes of travel to help reduce vehicle trips, yet there is little documentation on how effective T.O.D.s are at actually reducing vehicle trips and total vehicle miles traveled. This report attempts to calculate how successful Transit Oriented Developments in the Portland Metropolitan Region are at increasing …

The "Kiddie Cab" Industry Transformation In The 21st Century, Jason Wachs

Center for Urban Studies Publications and Reports

A new niche business has increased in the United States from a handful of private van services in 1992 to almost 250 nationwide. Referred to by many as "kiddie cabs," these private business are more than buses, iii that, they will chauffeur children to after school activities, the dentist, school, and anywhere else that children need to go.

The Kiddie Cab industry must explicitly be separated from publicly owned and operated transportation services for children such as paratransit services, shuttles for specific programs such as the YMCA, and any other transportation services for children that are currently funded and operated …

Time Point-Level Analysis Of Passenger Demand And Transit Service Reliability, Thomas J. Kimpel, James G. Strathman, Kenneth Dueker

Center for Urban Studies Publications and Reports

This paper provides a framework for analyzing transit service reliability and estimating passenger demand at the time point-level of analysis. It begins with a literature review of passenger demand modeling and transit service reliability analysis, and shows how advances in transportation technologies are producing vast amounts of data that encourage the use of new modeling techniques. Differences between route-level and time point-level demand modeling are discussed. Lastly, the results of the passenger demand and transit service reliability models estimated from Tri-Met BDS data are presented.

The Effects Of Roadway Capacity On Peak Narrowing - Evidence From 1995 Npts, Jihong Zhang, Anthony M. Rufolo, Kenneth Dueker, James G. Strathman

Center for Urban Studies Publications and Reports

Spreading of the peak is one effect of increased peak-period congestion. Due to peak spreading, the travel-time impact of congestion is mitigated for some travelers, but the inconvenience of traveling at a less-preferred time also has a cost. Alternatively, increases in capacity have their impacts on peak-period congestion mitigated by a narrowing of the peak. This reduces the travel-time savings, but it generates a benefit for those traveling closer to their preferred times. This benefit from capacity improvements has largely been ignored, and one reason is the difficulty of quantifying the effect. This paper reports on some crude attempts to …

A Clearinghouse Approach To Sharing Transportation Gis Data, Kenneth Dueker, J. Allison Butler, Paul Bender, Jihong Zhang

Center for Urban Studies Publications and Reports

Updating and maintaining Geographic Information Systems-Transportation data (GIS-T data) is proving difficult. Different database formats needed to support diverse applications leads to inconsistencies and inaccuracies, and duplication in updating. A clearinghouse approach is recommended for the collection and dissemination of new transportation features that can be segmented in different ways to meet the needs of various applications and inserted to update existing GIS-T databases. The clearinghouse approach is advantageous in that it is based on collecting data about new or changed transportation features once and uses the data many times to update existing databases.

A Framework For Gis-T Data Sharing, Kenneth Dueker, J. Allison Butler

Center for Urban Studies Publications and Reports

This paper develops a framework and principles for sharing of transportation data. The framework is intended to clarify roles among participants, data producers, data integrators, and data users. The principles are intended to provide guidance for the participants. Both the framework and the principles are based on an enterprise GIS-T data model that defines relations among transportation data elements. The data model guards against ambiguities and provides a basis for the development of the framework and principles for sharing of transportation data. There are two central principles. First is the uncoupling of graphics, topology, position, and characteristics. Second is the …

Sharing Transportation Gis Data, Kenneth Dueker, Paul Bender, Jihong Zhang

Center for Urban Studies Publications and Reports

Updating and maintaining Geographic Information Systems-Transportation data (GIS-T data) is proving difficult. Different database formats needed to support diverse applications leads to inconsistencies and inaccuracies, and duplication in updating. Dueker and Butler (1998) have proposed an Enterprise GIS-T data model that unbundles the various components of transportation data (network links, cartography, and attributes) to facilitate generating application-specific networks, and which eases updating and maintenance. However, developers of existing application-specific databases that employ integrated data models that bundle the network link with cartography and attributes are reluctant to step back to an intermediate form for managing their data. Consequently, attention is …

Analysis Of Induced Travel In The 1995 Npts, James G. Strathman, Kenneth Dueker, Thomas W. Sanchez, Jihong Zhang, Ann-Elizabeth Riis

Center for Urban Studies Publications and Reports

In this paper we estimate the relationship between road capacity and vehicle miles of travel (VMT) from a sample of 12,000 respondents from 48 urban areas in the 1995 Nationwide Personal Transportation Survey (NPTS). Our approach seeks to account for the effects of residential location, employment location, and commute mode choice in estimating the effect of capacity on VMT. VMT is found to be directly related to road capacity, as well as indirectly related through the influence of road capacity on residential and work place densities.

Bus Transit Operations Control: Review And An Experiment Involving Tri-Met’S Automated Bus Dispatching System, James G. Strathman, Thomas J. Kimpel, Kenneth Dueker

Center for Urban Studies Publications and Reports

An operations plan contains information on the provision of transit service, including intended service levels, vehicle availability, and driver schedules. Agency resources would be utilized efficiently if the operations plan could be executed without disruptions in service. When service disruptions occur, the aim of operations control is to optimize system performance given the current state of the system (Wilson et al., 1992). This typically involves actions intended to either return service to schedule or restore headways separating vehicles. Disruptions in service impose costs on transit providers in the form of reduced productivity and on passengers in the form of increased …

Bend Community Survey: Fall 1999, Deborah A. Howe, William A. Rabiega

Center for Urban Studies Publications and Reports

The City of Bend enters the new millennium following an unprecedented decade of development. Population was estimated at 47,635 in May of 1999. The city more than doubled its area with its 1998 annexations. Many public and private projects were built during the past decade, and many are in planning stages or under construction at this time. Given this history, it is prudent for city government to determine how well Bend’s citizens feel public services are performing, how they feel about communication with their government, and what their concerns are about Bend’s future course.

This document reports a community survey …

A Primer On Gis-T Databases, J. Allison Butler, Kenneth Dueker

Center for Urban Studies Publications and Reports

This paper describes the primary database design approaches that have been and are being used in geographic information system applications for transportation (GIS-T). While not intending to be exhaustive, the paper covers the primary approaches used in federal, state, and local transportation agencies.

Effective Transportation Demand Management: The Results Of Combining Parking Pricing, Transit Incentives, And Transportation Management In A Commercial District Of Portland, Oregon, Martha J. Bianco

Center for Urban Studies Publications and Reports

The Lloyd District is a high-density commercial and residential district located a short distance from downtown Portland, Oregon. Parking and transportation problems in the District have been a source of increasing contention for nearly a decade. As a result. in September of 1997. the City of Portland implemented a Lloyd District Partnership Plan, which consists of a number of elements aimed at curbing SOY use for the commute to and from the District. This plan included parking pricing in the form of meters, w'here on-street parking had previously been free: discounted transit passes: and other transportation demand management (TOM) strategies. …

Land Use And Growth Impacts From Highway Capacity Increases, Thomas W. Sanchez

Center for Urban Studies Publications and Reports

This analysis examined the historical relationship between land use changes and the location of capacity increasing highway projects in the State of Oregon from 1970 to 1990. Aerial photography for 18 cities was used to delineate the extent of urban development in each time period. A geographic information system (GIS) was used to assemble the data. Using this data, a logit regression model tested the significance of geographic variables such as proximity to highway projects, land use zoning classification, city size, and other spatial characteristics. The analytical methods used in this study incorporated a set of commonly used techniques to …

Effect Of Oregon's Axle-Weight-Distance Tax Incentive, Anthony M. Rufolo, Lois M. Bronfman, Eric Kuhner

Center for Urban Studies Publications and Reports

Oregon s weight-mile tax was amended in 1990 to provide for a lower tax rate for trucks weighing more than 80,000 pounds if they added axles. The additional axles within a weight class reduce the amount of road damage. The tax break was largely based on equity considerations, since trucks within a weight class tend to do less road damage if they have more axles; however, the tax reductions also created an economic incentive to add axles and thus reduce road damage. This article is a report on attempts to determine if the tax break actually led to an increase …