TRAFFIC CONTROL

Introduction.

The material in this chapter:

  • Places the system design, procurement, and installation tasks in perspective with respect to total system planning and implementation,
  • Describes alternative approaches to the procurement of systems, including contractor selection,
  • Describes the various elements of the design process, and
  • Describes elements of an approach to manage the system installation.

System Design

Traffic signal control systems are usually based, in large measure, on existing software that may be provided by a number of suppliers. These software functions may be modified or augmented by the specifications resulting from the design process. The agency procuring the traffic system may also have software or equipment specifications that require consideration during the design process. The design process described below should be considered with these issues in mind.

Agencies responsible for operation of traffic control systems often have standards for commonly employed field equipment. It may be necessary for compatibility and to simplify logistics to employ these standards for new systems to the extent possible.

High level design provides the transition between requirements and detailed design. It includes:
  • Definition of architecture.
  • Sub-system definition.
  • Sub-system verification plan development.
  • Interface identification.
Items such as the following may be included:
  • Development, evaluation and selection of alternatives. Examples include detector and communication technology.
  • Identification of approximate equipment locations.
  • Conduct of social, economic and environmental studies to assure compliance with federal and state regulations.
  • Planning for access to utility supplied power and communication facilities that may be required.
Engineer (Consultant) / Contractor Approach

The engineer (consultant) / contractor approach represents the traditional procedure for contracting within the traffic signal system community. Agencies have procured the majority of traffic control systems using this approach. On the basis of feasibility studies and system selection, the engineer (consultant) prepares the design plans, specifications, and estimates (PS&E) for the proposed system. Either an agency employee or a consultant can serve as the engineer. The agency then issues the completed PS&E to the contractor community, and receives bids in accordance with the agency's established practice.

Transportation Management Plans
  • This page includes resources related to Transportation Management Plan (TMP).
Internal Traffic Control Plans (ITCP)
  • One way to prevent these fatalities is to implement traffic patterns on jobsites to reduce the amount of backing up that is necessary and minimize the exposure of workers on foot to vehicles.