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Transportation Engineering

The Transportation Planning Process

CHAPTER 5

Basic Elements Of Transportation Planning

The transportation planning process comprises seven basic elements, which are interrelated and not necessarily carried out sequentially. The information acquired in one phase of the process may be helpful in some earlier or later phase, so there is a continuity of effort that should eventually result in a decision. The elements in the process are:

1. Situation definition
2. Problem definition
3. Search for solutions
4. Analysis of performance
5. Evaluation of alternatives
6. Choice of project
7. Specification and construction. Situation Definition

• involves all of the activities required to understand the situation that gave rise to the perceived need for a transportation improvement.
• The basic factors that created the present situation are described, and the scope of the system to be studied is delineated.
• Information about the surrounding area, its people, and their travel habits may be obtained.
• Previous reports and studies that may be relevant to the present situation are reviewed and summarized both the scope of the study and the domain of the system to be investigated are delineated.

Basic Elements Of Transportation Planning

The transportation planning process comprises seven basic elements, which are interrelated and not necessarily carried out sequentially. The information acquired in one phase of the process may be helpful in some earlier or later phase, so there is a continuity of effort that should eventually result in a decision. The elements in the process are:

1. Situation definition
2. Problem definition
3. Search for solutions
4. Analysis of performance
5. Evaluation of alternatives
6. Choice of project
7. Specification and construction. Search for Solutions

• In this phase of the planning process, consideration is given to a variety of ideas, designs, locations, and system configurations that might provide solutions to the problem.
• This is the brainstorming stage, in which many options may be proposed for later testing and evaluation.
• Alternatives can be proposed by any group or organization. In fact, the planning study may have been originated to determine the feasibility of a particular project or idea, such as adding bike lanes to reduce traffic volumes.
• Among the options that might be used are different types of transportation technology or vehicles, various system or network arrangements, and different methods of operation.

Basic Elements Of Transportation Planning

The transportation planning process comprises seven basic elements, which are interrelated and not necessarily carried out sequentially. The information acquired in one phase of the process may be helpful in some earlier or later phase, so there is a continuity of effort that should eventually result in a decision. The elements in the process are:

1. Situation definition
2. Problem definition
3. Search for solutions
4. Analysis of performance
5. Evaluation of alternatives
6. Choice of project
7. Specification and construction. Analysis of Performance

• The purpose of performance analysis is to estimate how each of the proposed alternatives would perform under present and future conditions.
• Included in this step is a determination of the investment cost of building the transportation project, as well as annual costs for maintenance and operation.
• This element also involves the use of mathematical models for estimating travel demand. The number of persons or vehicles that will use the system is determined, and these results, expressed in vehicles or persons/hour, serve as the basis for project design.
• Other information about the use of the system (such as trip length, travel by time of day, and vehicle occupancy) is also determined and used in calculating user benefits for various criteria or measures of effectiveness.

Basic Elements Of Transportation Planning

The transportation planning process comprises seven basic elements, which are interrelated and not necessarily carried out sequentially. The information acquired in one phase of the process may be helpful in some earlier or later phase, so there is a continuity of effort that should eventually result in a decision. The elements in the process are:

1. Situation definition
2. Problem definition
3. Search for solutions
4. Analysis of performance
5. Evaluation of alternatives
6. Choice of project
7. Specification and construction. Choice of Project

• Project selection is made after considering all the factors involved.
• In a simple situation— for example, where the project has been authorized and is in the design phase—a single criterion (such as cost) might be used and the chosen project would be the one with the lowest cost.
• With a more complex project, however, many factors have to be considered, and selection is based on how the results are perceived by those involved in decision making. If the project involves the community, it may be necessary to hold additional public hearings.
• It is possible that none of the alternatives will meet the criteria or standards, and additional investigations will be necessary.

Basic Elements Of Transportation Planning

The transportation planning process comprises seven basic elements, which are interrelated and not necessarily carried out sequentially. The information acquired in one phase of the process may be helpful in some earlier or later phase, so there is a continuity of effort that should eventually result in a decision. The elements in the process are:

1. Situation definition
2. Problem definition
3. Search for solutions
4. Analysis of performance
5. Evaluation of alternatives
6. Choice of project
7. Specification and construction. Specification and Construction

• Once the transportation project has been selected, the project moves into a detailed design phase in which each of the components of the facility is specified.
• For a transportation facility, this involves its physical location, geometric dimensions, and structural configuration.
• Design plans are produced that can be used by contractors to estimate the construction cost of building the project.
• When a construction firm is selected, these plans will be the basis on which the project will be built.

Urban Transportation Planning

Urban transportation planning involves the evaluation and selection of highway or transit facilities to serve present and future land uses. For example, the construction of a new shopping center, airport, or convention center will require additional transportation services. Also, new residential development, office space, and industrial parks will generate additional traffic, requiring the creation or expansion of roads and transit services. The elements in the process are:

1. Inventory of Existing Travel and Facilities 4 ) Estimation of Project Cost and
2. Establishment of Goals and Objectives Travel Demand.
3. Generation of Alternatives 5 ) Evaluation of Alternatives 6 ) Choice of Project Inventory of Existing Travel and Facilities

• Data-gathering activity in which urban travel characteristics are described for each defined geographic unit or traffic zone within the study area.
• Inventories and surveys are made to determine traffic volumes, land uses, origins and destinations of travelers, population, employment, and economic activity.
• Inventories are made of existing transportation facilities, both highway and transit.
• Capacity, speed, travel time, and traffic volume are determined.
• The information gathered is summarized by geographic areas called transportation analysis zones (TAZ).

Urban Transportation Planning

Urban transportation planning involves the evaluation and selection of highway or transit facilities to serve present and future land uses. For example, the construction of a new shopping center, airport, or convention center will require additional transportation services. Also, new residential development, office space, and industrial parks will generate additional traffic, requiring the creation or expansion of roads and transit services. The elements in the process are:

1. Inventory of Existing Travel and Facilities 4 ) Estimation of Project Cost and
2. Establishment of Goals and Objectives Travel Demand.
3. Generation of Alternatives 5 ) Evaluation of Alternatives 6 ) Choice of Project Establishment of Goals and Objectives

• The urban transportation study is carried out to develop a program of highway and transit projects that should be completed in the future.
• Thus, a statement of goals, objectives, and standards is prepared that identifies deficiencies in the existing system, desired improvements, and what is to be achieved by the transportation improvements.
• For example, if a transit authority is considering the possibility of extending an existing rail line into a newly developed area of the city, its objectives for the new service might be to maximize its revenue from operations, maximize ridership, promote development, and attract the largest number of auto users so as to relieve traffic congestion.

Urban Transportation Planning

Urban transportation planning involves the evaluation and selection of highway or transit facilities to serve present and future land uses. For example, the construction of a new shopping center, airport, or convention center will require additional transportation services. Also, new residential development, office space, and industrial parks will generate additional traffic, requiring the creation or expansion of roads and transit services. The elements in the process are:

1. Inventory of Existing Travel and Facilities 4 ) Estimation of Project Cost and
2. Establishment of Goals and Objectives Travel Demand.
3. Generation of Alternatives 5 ) Evaluation of Alternatives 6 ) Choice of Project Estimation of Project Cost and Travel Demand

• Project cost estimation at the planning stage may be hampered either because the project has not yet been well defined or because a significant amount of time has passed since the project’s cost was previously estimated, rendering the older estimate out of date.
• To address the first problem, many transportation agencies maintain a set of unit costs that allows for a quick determination in the absence of more detailed data.
• Future travel is determined by forecasting future land use in terms of the economic activity and population that the land use in each TAZ (transportation analysis zones) will produce.
• The size of the TAZ will depend on the nature of the transportation study, and it is important that the number of zones be adequate for the type of problem being investigated.

Urban Transportation Planning

Urban transportation planning involves the evaluation and selection of highway or transit facilities to serve present and future land uses. For example, the construction of a new shopping center, airport, or convention center will require additional transportation services. Also, new residential development, office space, and industrial parks will generate additional traffic, requiring the creation or expansion of roads and transit services. The elements in the process are:

1. Inventory of Existing Travel and Facilities 4 ) Estimation of Project Cost and
2. Establishment of Goals and Objectives Travel Demand.
3. Generation of Alternatives 5 ) Evaluation of Alternatives 6 ) Choice of Project Evaluation of Alternatives

• This phase of the process is similar in concept to what was described earlier but can be complex in practice because of the conflicting objectives and diverse groups that will be affected by an urban transportation project.
• Among the groups that could be affected are the traveling public (user), the highway or transit agencies (operator), and the nontraveling public (community).
• The purpose of the evaluation process is to identify feasible alternatives in terms of cost and traffic capacity, to estimate the effects of each alternative in terms of the objectives expressed, and to assist in identifying those alternatives that will serve the traveling public and be acceptable to the community.
• Of particular importance are the environmental assessments mandated in most urban transportation studies.

Urban Transportation Planning

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