Work Zone Mobility and Safety Program

Work Zone Road User Costs - Concepts and Applications

Chapter 1. Introduction

1.1 Background

Vehicle miles traveled (VMT) on U.S. highways doubled in the last three decades, while the highway lane miles of all functional classes increased by only 5 percent during the same period. (FHWA, Our Nation's Highways 2010, Publication No. FHWA-PL-10-023, Office of Highway Policy Information, Federal Highway Administration Washington D.C., 2010.) The cost of congestion, incurred by the road users for travel delay and extra vehicle fuel, has risen from $24 billion in 1982 to $115 billion in 2009, while the yearly peak delay has risen from 14 hours to 34 hours during the same period. To keep up with the pace of growing congestion, the investment in our highways through Federal, State, or local funding has tripled over the same period.

As a result, the number of significant construction activities has been increasing over the years, and the majority of active work zones are located on existing roads already carrying traffic. (Federal Highway Administration, Facts and Statistics, Work Zone Mobility and Safety Program, Office of Operations, Federal Highway Administration Washington D.C., 2008.) These activities typically are undertaken in heavily urbanized areas and can cause traffic disruptions, safety implications to motorists and construction workers, and negative impacts on local businesses and the community. These problems are aggravated by delays in project delivery, a common problem with highway construction.

To address these issues effectively, the Federal Highway Administration (FHWA) has established several programs and measures to enhance work zone mobility and safety and to shorten project construction time, such as:

  • Work Zone Mobility and Safety Rule — Effective since October 2007, this rule requires all State and local highway agencies to develop and implement policies and procedures for assessing and managing work zone impacts on individual projects. The goal of the rule is to provide a decision making framework for considering the broader work zone safety and mobility impacts across project development stages, and to facilitate the implementation of additional strategies that help manage these impacts during project delivery. The provisions of the rule apply to all highway construction projects financed in whole or in part with Federal-aid highway funds. (Frequently Asked Questions for the Work Zone Safety and Mobility Rule.)
  • Special Experimental Program (SEP) No. 14 — Established in 1988, the SEP-14 program serves as a functional platform to evaluate "project-specific" innovative contracting practices on Federal-aid projects that focus on shortening project delivery time and minimizing work zone road user impacts without affecting product quality. This program provides some administrative flexibility to State highway agencies from specific Federal legislative requirements typically required in Federal-aid projects. After a period of evaluation under this program, alternative contracting practices such as cost plus time bidding, lane rental, and design-build contracting were declared suitable for operational use. (FWHA, Special Experimental Projects No. 14 - Alternative Contracting, Office of Program Administration, Federal Highway Administration, Washington, DC.)
  • Highways for LIFE (HfL) — Under FHWA HfL pilot program established by the U.S. Congress established in 2005, the FHWA offers technical assistance and incentives to highway agencies to use readily available but rarely used innovations in standard practice that focus on shortening project delivery, improving mobility and safety through work zones, and enhancing quality and user satisfaction.
  • Every Day Counts (EDC) — The EDC Innovation Initiative was introduced in 2010 to identify and deploy innovation aimed at shortening project delivery, enhancing roadway safety, and protecting the environment. The core elements of this initiative include:
    • Accelerating Technology and Innovation Deployment — This toolkit includes effective, field-proven, market ready technologies such as Prefabricated Bridge, Safety Edge, Adaptive Signal Control for widespread deployment to improve highway mobility and safety.
    • Shortening Project Delivery — This toolkit presents various approaches for improving project delivery times by providing solutions to a number of frequently cited problem areas that impede on-time project delivery. The toolbox includes strategies for accelerating project delivery and eliminating time-consuming duplication of effort, and by encouraging the use of existing regulatory flexibilities.

In all these contexts, the goal of minimizing the negative work zone impacts gains prominence through effective transportation management plans (TMP), alternative program delivery and contracting strategies, and accelerated construction techniques focusing on quicker project delivery. It is equally imperative to quantify these negative impacts to help devise policy and mitigation measures, implement them, and further evaluate and monitor their performance. The concept of “work zone road user costs” (WZ RUC) provides the economic basis for quantifying the work zone impacts for use in work zone management.

The use of WZ RUC in transportation decision making is not a new phenomenon. Though WZ RUC is not a part of an agency’s budgeted cost, it serves as one of the surrogate economic measures representing the public’s interests in the agency’s decision making process. The WZ RUC is applied in various stages a transportation facility’s life cycle including planning, design, construction, operations and preservation. The WZ RUC often is applied in an agency’s life cycle cost analysis (LCCA) and benefit-cost decisions relating to capital investment, system preservation and improvements, strategy selection, and contract administration. The WZ RUC has been traditionally applied in the LCCA of highway structures such as pavements and bridges, and the process is well established. However, the application of WZ RUC in other areas is still nascent.

Several surveys cited in the literature have reported that, despite the importance of WZ RUC in an agency’s decision making, not all States compute WZ RUC. (Saito, M., M. R. Adams, T. G. Jin, Development of a User Cost Estimation Procedure for Work Zones, Report No. UT-05.11, Utah Department of Transportation, Salt Lake City, UT, 2005. Salem, O. and A. Genaidy, Improved Models for User Costs Analysis, Report No. FHWA/OH-2008/3, Ohio Department of Transportation, Columbus, OH, 2008.)Furthermore, among those States computing WZ RUC, there is no apparent uniformity in their practices with regard to defining the cost components, deriving unit costs for travel delay and vehicle operating cost computations, estimating lane capacity values, and travel delay/queuing algorithms. For example, some agencies may consider the average vehicle occupancy in deriving the unit cost for travel delay, while others may not take vehicle occupancy into account. Owing to the differences in regional characteristics and agency needs, these differences are justifiable; however, the basis for inconsistency in their approaches remains largely unknown. These differences in approach speak to the need for an updated guidance on user cost estimation.

1.2 Objectives and Scope

The primary objective of this report is to present the concepts that transportation practitioners can use to:

  • Perform work zone road user cost analysis.
  • Apply WZ RUC analysis methods/tools in maintenance of traffic (MOT) alternative selection.
  • Apply WZ RUC analysis methods/tools in contract administration to expedite project completion and minimize adverse work zone effects.

This document presents a detailed discussion of the key components of WZ RUC, input needs, and available tools. Step-by-step procedures to derive unit costs for monetary RUC components based on available cost sources and models are also provided. Finally, this document presents a process for applying RUC concepts in selecting an appropriate MOT and contracting strategy for managing work zone impacts and shortening project completion time. Because of the differences in agency decision making processes, it is expected that each agency will modify the recommended procedures to meet its specific needs.

1.3 Report Organization and Use

This report is organized into six chapters.

Chapter 1 of this report presents the introductory material. It provides a discussion on the importance of WZ RUC in enhancing work zone mobility and safety and shortening project construction time.

Chapter 2 presents procedures for computing various quantifiable components and their unit costs. It also presents a discussion of the input requirements for WZ RUC analysis and various tools available for use.

Chapter 3 presents the application of WZ RUC in identifying and evaluating potential traffic control strategies for MOT alternative analysis.

Chapter 4 presents a discussion of various alternative contracting strategies that focus on reducing WZ RUC and minimizing work zone impacts. It also presents an approach for selecting an appropriate schedule-focused contracting strategy based on project needs. It also discusses incentive/disincentive amounts and identifying a balance between construction costs and the level of schedule acceleration required to minimize WZ RUC.

Chapter 5 presents three case studies illustrating the application of WZ RUC analysis and concepts in each application area: MOT alternative analysis, alternative contracting strategy selection, and benefit-cost analysis of conventional and accelerated construction techniques.

Chapter 6 presents the key components of a typical WZ RUC analysis report covering background information of the project, data collection, existing conditions, impact assessment, alternative analysis, and recommendations.

You will need the Adobe Reader to view the PDFs on this page.

previous | next
Office of Operations