This synthesis reports how various agencies have acted on the various components of an access management program, what have been barriers to action, and how new efforts might improve implementation of access management strategies. Primary focus areas considered are legal and legislative bases, contents of policies and programs, implementation aspects, reported effectiveness of program implementation, and profiles of contemporary practice. This synthesis reports on the state of the practice with respect to planning, highway design, development review and permitting, and other focus areas where access management is typically incorporated. The emphasis is placed on states, but counties, municipalities, and metropolitan planning organizations are also considered.
Managing existing and newly constructed highway corridors has recently become a significant concern in many states, including Iowa. As urban land and land on the urban fringe develops, there is pressure to add features such as commercial driveways, at-grade public road intersections, and traffic signals to arterial highway routes that should primarily serve high-speed traffic. This diminishes the speed and traffic capacity of such roadways and can also cause significant safety issues. if mobility and safety are diminished, the value of the highway investment is diminished. Since a major highway corridor improvement may cost tens of millions of dollars or more, corridor management is as critical to preserving that investment as is more "hard side" management practices such as pavement or bridge management. Corridor management is a process that applies access management principles to highway corridors in an attempt to balance the competing needs of traffic service, safety, and support for land development. This project helped to identify routes that should be given high priority for corridor management. The pilot study in the form of two corridor management case studies provides an analytical process that can be replicated along the other Iowa commuting corridors using commonly available transportation and land use data resources. It also offers a general set of guidelines for the Iowa Department of Transportation to use in the development of its own comprehensive corridor management program.
This research project was intended to produce a strategy for addressing current and future access management problems on state highway routes located just outside urban areas that serve as major routes for commuting into and out of major employment centers in Iowa. There were two basic goals: (1) to develop a ranking system for identifying high-priority segments for access management treatments on primary highways outside metro and urban areas and (2) to focus efforts on routes that are major commuting routes at present and in the future. The project focused on four-lane expressways and two-lane arterials most likely to serve extensive commuter traffic. Available spatial and statistical data were used to identify existing and possible future problem corridors with respect to access management. The research team developed a scheme for ranking commuter routes based on their need for attention to access management. This project was able to produce rankings for corridors based on a variety of factors, including proportion of crashes that appear to be access-related, severity of those crashes, and potential for improvement along corridors. Frequency and loss were found to be highly rank correlated; because of this, these indicators were not used together in developing final priority rankings. Most of the highest ranked routes are on two-lane rural cross sections, but a few are four-lane expressways with at-grade private driveways and public road intersections. The most important conclusion of the ranking system is that many of the poor-performing corridors are located in a single Iowa Department of Transportation district near two urban areas--Des Moines and Ames. A comprehensive approach to managing access along commuting corridors should be developed first in this district since the potential benefits would be highest in that region.
The papers presented in this volume should be of interest to engineers, scientists and managers who are involved in the planning and management of urban transportation and transport policy.
"Since the publication of the first edition of the Access Management Manual, the context for transportation planning and roadway design in the United States has been transformed. Transportation agencies and local governments are under growing pressure to integrate land use and transportation policy and achieve a more sustainable, energy-efficient transportation system. This second edition of the manual responds to these developments by addressing access management comprehensively, as a critical part of network and land use planning. The content is interdisciplinary, with guidance pertinent to various levels of government as well as to pedestrians, bicyclists, and motorized vehicles, including trucks and buses, and is strongly grounded in decades of research, engineering science, and professional experience. Greater emphasis is placed on appropriate location of access, and guidance is refined to provide appropriate consideration of context and community issues. Substantial updates aid state and local agencies in managing access to corridor development effectively. Specific guidance on network and circulation planning and modal considerations is included, as well as guidance on effective site access and circulation design. A chapter on corridor management reinforces these concepts with a framework for application of access management in different contexts, along with appropriate strategies for each context. There are also new chapters on network planning, regional access management policies and programs, interchange area access management, auxiliary lane warrants and design, and right-of-way and access control. The manual concludes with an extensive menu of access management techniques and information on their application"--Provided by publisher.
This collection contains 77 papers exploring transportation, land use, and air quality presented at a specialty conference, held in Portland, Oregon, May 17-20, 1998.
