Office of Operations
21st Century Operations Using 21st Century Technologies

Designing for Transportation Management and Operations: A Primer

1. Designing for Operations

1.1 Introduction to Designing for Operations

Transportation agencies across the United States are looking for ways to provide safe, efficient, and reliable travel across modes and jurisdictions under increasingly constrained fiscal environments. The public, business leaders, and elected officials want reliable goods movement, timely and accurate traveler information, safe and quick incident clearance, and greater options in transportation modes, routes, and services. To address the need for mobility, safety, and security, many transportation agencies have integrated management and operations into their set of solutions. Management and operations strategies can often improve transportation system performance significantly and be deployed more quickly and more cost-effectively than traditional capacity expansion projects. Management and operations (M&O) strategies focus on getting the most efficient and safest use out of existing or planned infrastructure through activities such as traffic incident management, traveler information dissemination, traffic signal coordination, and work zone management. M&O strategies are funded and implemented as stand-alone projects or combined with larger projects such as highway reconstruction.

Figure 1. Locations of variable message signs should be selected for maximum effectiveness such as in areas of frequent hazardous weather or traffic incidents and prior to traveler decision points.
Variable message sign hung on a gantry warning drivers of high winds in a mountainous area ahead.
(Source: Nevada Department of Transportation)

The effective management and operation of the transportation system often requires traditional infrastructure (e.g., roadways and other civil infrastructure) to be designed to support M&O strategies. This includes roadway design for freeways and arterials, transit system design, as well as strategic integration of intelligent transportation systems (ITS) on roadways and rail systems. For example, a high volume highway segment with a full-depth shoulder sufficient to support traffic is needed for bus-on-shoulders, an M&O strategy in which only public buses may use the shoulder to minimize delay during peak congestion periods. Additionally, the installation of variable message signs (VMS) in locations prior to significant route or modal decision points for travelers or common incident areas supports relevant, actionable traveler information to the public. Other examples of roadway design treatments that are important for improving the management and operation of the facility include:

  • Median crossovers, which allow for incident responders to quickly access the opposite side of the road;
  • Crash investigation sites, which reduce impacts associated collecting incident information;
  • Snow fences, which reduce blowing snow and drifts on the road; and
  • Emergency access between interchanges, which decrease response time to incidents; and
  • Bus turnouts, which ease arterial congestion.
Traditionally, the needs of M&O strategies have not been fully considered in roadway infrastructure design, including major projects such as road, bridge, and tunnel construction, roadway expansion or extension, bridge restoration, tunnel rehabilitation, and re-paving. Roadway design processes take into consideration some aspects of how the facility will operate by considering peak hour design traffic volumes, expected truck volumes, signing, striping and pavement marking needs, desired design level of service, and design speed. However, critical M&O considerations that support the broad array of strategies listed in Section 1.2 are often addressed in an ad-hoc manner or are given insufficient consideration during project development. This means that the operations needs of the system are either not sufficiently addressed or agencies must retrofit roadways after they are constructed or reconstructed. This latter approach is usually less effective and more expensive in terms of construction, user, and right-of-way costs than including operational needs in the original design. At times, retrofitting the roadway for operations forces the need for design exceptions that may raise safety concerns. These are issues that typically can be eliminated if operations is considered during the design and preliminary engineering stages.
Figure 2. An example of a design treatment to improve the operations of a roadway is snow fences that reduce blowing snow and drifts on the road. Shown are the simple design guidance and an image of the corresponding implementation in Minnesota.
Implementation of a snow fence in a corn field in Minnesota followed by diagram containing simple design guidance.
(Photo Source: Dan Gullickson, MnDOT, Diagram Source: MnDOT)

This primer is focused on designing for operations; i.e., the collaborative and systematic consideration of management and operations during transportation project design and development. Effectively designing for operations involves the development and application of design policies, procedures, and strategies that support transportation management and operations. Considering operations needs during the design process requires transportation design professionals to work closely with those who have expertise in transportation operations, intelligent transportation, and transportation technology. Design professionals should also anticipate working with practitioners from planning, transit, freight, and TIM as well as staff from other agencies in order to fully identify, prioritize, and incorporate operations needs into the infrastructure design. There are several entry points for integrating M&O strategies into the traditional project design process, as described in this primer. Designing for operations is typically reflected in increased or formalized collaboration between designers and operators and the development of design guidelines and procedures that reflect a broad range of operational considerations.

Successful integration of M&O considerations into the design process means that:

  • Roadway and transit system infrastructure is designed to facilitate the needs of day-to-day system management and operations and meet transportation system performance targets for efficiency, reliability, travel options, and safety.
  • ITS deployments are designed using systems engineering, and existing and future operational uses of ITS are incorporated into transportation facility design.
  • Operational strategies are considered as credible alternatives to infrastructure expansion during project design. The relatively low-cost, high-impact, and flexible nature (i.e., scalable to changing demands) of M&O strategies makes them attractive deployment options.

There are regions and States across the United States that are moving forward with the incorporation of operations needs into project design because they recognize the benefits in terms of cost savings and system performance. For example, the published policies and procedures of the Regional Transportation Commission (RTC) of Southern Nevada require all projects to be designed to the standards of the Regional Intelligent Transportation Systems Architecture adopted by the RTC.1 Additionally, copies of all project plans must be provided to the Freeway and Arterial System of Transportation (FAST) organization for review. The policies and procedures also require the consideration of raised medians to reduce left turn conflicts and pedestrian refuge during project design. Also, installing conduit should be considered during project construction if traffic signals are anticipated in the future. Another example is from the Delaware Department of Transportation where there is a review of M&O requirements in each design phase of every capital transportation project.

The congestion management process (CMP) has also served as a motivator for designing for operations. For example, the Delaware Valley Regional Planning Commission (DVRPC) requires as part of its CMP that any project that adds major capacity for single-occupancy vehicles (SOV) includes supplemental strategies to reduce congestion and get the most from infrastructure investments. The final engineering for a major SOV capacity adding project must include a list of supplemental strategies to be included in the transportation improvement program (TIP) for funding. These supplemental strategies—such as traffic signal improvements, signal preemption for emergency, park-and-ride lots, and engineering strategies to improve traffic circulation—work to improve the overall management and operation of the facility.2

Other examples of designing for operations practices can be found in Section 1.5.

Figure 3. Express high occupancy/toll lanes with variable pricing is an M&O strategy increasingly used in the United States.
A message sign depicting current pricing for HOT lanes mounted on an overhead gantry.
(Source: SAIC)

1.2 Management and Operations Overview

Systematic consideration of M&O strategies during the design process is at the core of designing for operations. Transportation systems management and operations is defined by the legislation "Moving Ahead for Progress in the 21st Century" (MAP-21) as the use of "integrated strategies to optimize the performance of existing infrastructure through the implementation of multimodal and intermodal, cross-jurisdictional systems, services, and projects designed to preserve capacity and improve the security, safety, and reliability of the transportation system."3 M&O strategies encompass many activities, such as:

  • Traffic incident management.
  • Traffic detection and surveillance.
  • Corridor, freeway, and arterial management.
  • Active transportation and demand management.
  • Work zone management.
  • Road weather management.
  • Emergency management.
  • Traveler information services
  • Congestion pricing.
  • Parking management.
  • Automated enforcement.
  • Traffic control.
  • Commercial vehicle operations.
  • Freight management.
  • Coordination of highway, rail, transit, bicycle, and pedestrian operations.

Applying the concepts of designing for operations in a cohesive and standardized manner decreases long-term costs, saves contract and staff labor time, and can improve operational performance of the transportation system. For example:

  • Installing conduit during major roadway or bridge reconstruction projects on a corridor can reduce the future communications systems costs of the corridor's freeway management system.
  • Including a full-depth shoulder with sufficient design to support traffic in a reconstruction project can allow the shoulder to be utilized as part of an alternative capacity expansion concept such as allowing bus use of highway shoulders.
  • Locating an access door in a noise wall at a critical location can decrease the response time to a major incident on a freeway.

Management and operations also includes the regional coordination required for implementing operational investments such as communications networks and traffic incident management in an integrated or interoperable manner.

Successful M&O practices positively impact mobility, accessibility, safety, reliability, community life, economic vitality, and environmental quality and help transportation agencies meet their customers' needs. In addition, many agencies have found that the benefits of M&O strategies can significantly outweigh the costs (versus traditional strategies). Proactive management of transportation systems in real-time and at all hours of the day not only represents the future of operations but is essential to responding effectively to variable traffic conditions caused by events such as incidents, work zones, and weather effects.

Figure 4. Access doors in noise walls like this one on Virginia State Route 267 can decrease incident response time.
Access door in a noise wall.
(Source: SAIC)

1.3 Why Integrate Operations into Design?

To maximize the safety, reliability, and efficiency of the transportation system, it is crucial that roadways, bridges, and transit infrastructure be designed to better manage demand and respond to incidents and other events. Designing for operations improves the integration of operational considerations throughout the transportation project development lifecycle, resulting in better resource utilization, improved maintenance and asset management practices through enhanced collaboration, and effectively designed and deployed infrastructure improvements. Some advantages of incorporating operations into traditional design processes include:

  • Increasing the benefits derived from a given infrastructure investment.
  • Designing a safer facility for users, emergency responders, maintenance staff, and other operators.
  • Designing for future work zones so that road users experience less interruption.
  • Reducing the costs for future operational and ITS deployments.
  • Reducing congestion and improving travel time reliability.

1.4 Primer Audience and Overview

The primer is written for several primary audiences:

  • Roadway designers.
  • Transportation planners.
  • Transportation operations professionals.
  • Transportation agency managers.

This primer introduces the concept of designing for operations, describes tools and institutional approaches to assist transportation agencies in considering operations in their design procedures, and points out some specific design considerations for various operations strategies. The tools and approaches to aid in designing for operations may include checklists for designers to reference operational considerations, formation of a technical advisement committee with operations expertise, or agency policies that instruct designers on how to incorporate operational elements within the project development process. These will benefit multiple practitioner groups, including planners, project designers, scoping engineers, maintenance and traffic managers, and contract development personnel.

The primer is organized into four sections:

Chapter 1. Designing for Operations (the current chapter) – This chapter introduces the term "designing for operations" and explains its value and purpose. It orients the reader to this primer and provides examples of successful designing for operations practices being implemented by State departments of transportation (DOTs) and metropolitan planning organizations (MPOs). Lastly, it identifies limitations in current design practices that must be overcome in order to enable effective designing for operations.

Chapter 2. Putting it into Action – Policies and Procedures – This chapter defines the key actions agencies can take to better incorporate operational considerations into the design process. It identifies opportunities to implement policies and procedures and to encourage communication and collaboration between operations, design, and planning disciplines. It also provides general approaches for agencies to incorporate operations into the transportation design process.

Chapter 3. Design Considerations for Specific Types of Operations Strategies – This chapter provides a toolbox of design considerations to support M&O strategies.

Chapter 4. A Way Forward – This chapter ties together the major themes of the primer and provides a concise summary of the primary lessons for the reader.

Who Should Read This Document and Why?

  • Roadway designers will gain perspective regarding the types of operational strategies that are available and how features that support those strategies can be integrated into traditional design.
  • Transportation operations professionals will be engaged to ensure that operational strategies are included in the design process where appropriate.
  • Transportation planners will be equipped to better identify project relationships and synergies (such as those between infrastructure and operations) that can help improve the long range planning and transportation improvement program development processes.
  • Transportation agency managers will understand the benefits that can be derived from placing a greater emphasis on operations throughout the project lifecycle.

1.5 Examples of Effective Designing for Operations Practices

Across the United States, there are several agencies that have adopted effective approaches for integrating operations considerations into the design of transportation infrastructure. The examples highlighted below illustrate a range of practices, from the consideration of operational improvements as part of a project design prior to programming the project, to the use of ITS design manuals and guidelines. A few of the examples showcase collaboration between designers, operations experts, and professionals with other areas of expertise to ensure that project designs take into account a broad range of needs.

The California Department of Transportation (Caltrans) and its local partners develop Corridor System Management Plans (CSMP) for those corridors that are heavily congested. Through these efforts, M&O strategies are routinely identified and included as a package of improvements for the corridor.4 The CSMP identifies bottlenecks, which are defined as "localized sections of highway where traffic experiences reduced speeds and delays due to recurring operational conditions or nonrecurring traffic-influencing events," and looks for opportunities to address the bottlenecks. Bottleneck reduction strategies include several M&O strategies such as traffic signal re-timing, access management, and providing traffic diversion information. As part of this effort, Caltrans may conduct a localized bottleneck reduction audit by reviewing traditional large-scale corridor studies in order to identify opportunities to deploy low cost bottleneck reduction strategies within a package of improvements.

In 2012, Portland Metro, the City of Portland, Portland State University, and Metro's regional partners developed The Portland Multimodal Arterial Performance Management Regional Concept of Transportation Operations (RCTO) to provide regional guidance for collecting automated multimodal performance measures on arterial roadways.5 The RCTO is the Portland region's next step in advancing performance-based transportation planning and investment decision-making. The guidance includes detector technology options, design considerations for installation of data collection technology, and intersection diagrams depicting where detection is needed. The RCTO recommends updates to the Oregon DOT and local agency design standards. As new projects arise, Metro is encouraging the installation of necessary field equipment and communications to collect all eligible performance measures at given locations.

Figure 5. Diagram from Portland Multimodal Arterial Performance Management Implementation Guidance depicting typical locations for collecting multimodal arterial data.6
Diagram depicting an east-west arterial intersecting a north-south arterial and, further east, a local street or collector. Icons on the diagram indicated the locations where data is collected on intersection operations and transit signal priority, transit measures, emissions, bicycle and vehicle detection zones, pedestrian an bicycle routes, travel time data collectors, and detectors to identify vehicle classification, speed, and count.

The Florida DOT's Transportation Systems Management and Operations (TSM&O) Program7 is a prime example of a program that formalizes designing for operations practices through stakeholder collaboration. The TSM&O Program is implemented throughout all departments, including design, where operational aspects of a facility are to be designed and built during construction for easier long-term operations and maintenance of the facility.8 The program's focus is measuring performance, actively managing the multimodal transportation network, and delivering positive safety and mobility outcomes to the traveling public. To do this, TSM&O relies on collaborative relationships between partners. The TSM&O partners are comprised of public transportation agencies who serve together as one cohesive entity to make cost-effective investment decisions. This cohesiveness serves to improve communications, coordination, and collaboration amongst transportation partners with diverse perspectives, leading to more designs that consider operations.

The Florida DOT District 4 has established a project development and management structure that formally includes input from operational agencies, such as signal and transit departments. The objective is to reflect operational elements in project design and operational strategies that are consistent with the current and planned infrastructure. The overall process makes it clear to the District how its operational requirements are being reflected in project development.

The Washington State DOT (WSDOT) has formed a System Operations and Management (SOM) Committee, which is comprised of a cross-cutting group of program managers from the DOT's regions and headquarters. Currently, the group is working to shape the design process to be more flexible for implementing creative operational solutions. Each member represents an interest area such as operations, system performance, design, planning, tolling, program management, multi-modal, commercial vehicles, and travel information. The group is tasked with identifying and solving the many evolving issues that arise as the agency moves toward being more operations focused. The committee's ultimate goal is to improve capacity and travel reliability without traditional levels of infrastructure investment. WSDOT also provides design guidelines for minor operational enhancement projects (low-cost enhancements intended to improve the safety and efficiency of the highway system) in the WSDOT Design Manual, Minor Operational Enhancement Projects (Chapter 1110).9 These projects are considered as alternatives to larger, more costly traditional projects. An important characteristic of these projects is the ability to quickly develop and implement them without a cumbersome approval process. In order to achieve this, design policies and guidelines are applied in the development and approval processes in the same manner with each project. This approach is part of the DOT's statewide Minor Operational Enhancement Projects Program (referred to as the "Q" Program), which is one of the four major programs (i.e., improvement, maintenance, preservation, and traffic operations) within the WSDOT's Highway System Plan. Elements within the Q Program include: traffic operations program management, traffic operations program operations, and special advanced technology projects.10

The Pennsylvania DOT has integrated operational considerations into its design manual series and has developed the Intelligent Transportation Systems Design Guide which documents strategy selection, design variables, site selection considerations, systems engineering considerations, and site design considerations. Details are provided on which devices are appropriate based on roadway conditions as well as how ITS elements should be deployed within existing constraints, such as the cost of connection to communications and power utilities, safe access for maintenance staff, and available right-of-way. This guide provides a level of detail that allows non-ITS practitioners to incorporate ITS design elements into projects in a cohesive and consistent manner.11

It is important to note that the example practices and programs above are mainstreamed into the agencies' everyday business practices. WSDOT has a section in its design manual dedicated to the Q program, and Florida DOT has moved forward with a strategic plan and business plan for how to implement TSM&O within the existing policies and procedures of the DOT. Missouri DOT has established the use of core teams as a preferred practice, as mentioned in its Engineering Policy Guide.12 Caltrans promotes localized bottleneck reduction audits at the district level to identify improvements related to bottlenecks. These programs foster the type of cross-cutting strategies necessary for designing for operations.

1.6 Limitations in Current Design Practices

Some transportation agencies are now placing a greater emphasis on operations during the design process; however, the methods for applying this practice are inconsistent due to gaps that exist within current project development processes and a lack of sufficient communication between designers and operators.

Many agencies at the State, regional, and local levels have embraced M&O practices and the use of ITS. The U.S. DOT ITS Deployment Tracking data suggest steady expansion of the Nation's ITS infrastructure and operational practices.13 A significant number of States and regions are guided by formal M&O or ITS strategic plans and architectures and are making progress in planning for operations.

Despite this progress, there is still a disconnect between infrastructure design and operations in many transportation agencies. Current processes for the development of roadway or bridge project plans typically involve following a set of design criteria, such as agency-specific guidelines or those published in the American Association of State Highway and Transportation Officials' (AASHTO) A Policy on Geometric Design of Highways and Streets.14 These criteria require highway engineers to identify design controls, some of which are pre-determined (e.g., terrain, urban vs. rural, classification of the road), while others are project-specific. The Federal Highway Administration (FHWA) and AASHTO both note that the basis of geometric criteria should include additional factors such as cost, maintainability, safety, and traffic operations.15 Reasons for the disconnect between design and operations include the lack of policies that support the integration of M&O considerations into design as a routine way of doing business and the lack of involvement of internal and external facility operators during the project development process. Facility operator perspectives are critical not only for identifying necessary operations infrastructure, but for providing input into design decisions that influence ongoing maintenance and support of the deployed infrastructure and the manner in which the infrastructure will be used on a day-to-day basis. For example, agency traffic management operations personnel could provide recommendations on the placement and orientation of traffic surveillance equipment to ensure the data collected meet operational objectives and to facilitate access to the equipment for future maintenance.

In some transportation agencies, roadway designers may work in settings where there is limited collaboration with operations staff, so the resulting project delivery process does not maximize the opportunity to incorporate operations elements. The consequences of this disconnected process are often that more time and money are used to retrofit infrastructure for enhanced operations or that the transportation system does not perform to its potential level of service.

1.6.1 Institutional Challenges

Due to the major cost of providing new capacity, agencies have started to focus on operations as a tool to maximize the efficiency of transportation networks. But even as operations is beginning to hold an elevated status, operations and design are still too often disconnected in transportation agencies. When transportation operations, planning, and roadway design occur in separate silos within an organization or region, awareness and understanding of the need to design for operations among agency staff and management is limited, and opportunities to maximize the performance of infrastructure investments are lost. By integrating these worlds, the system performance advantages and cost savings of operational improvements may be leveraged. As emphasis shifts from building new roadway facilities to maximizing operations on existing roadways, agencies are instituting mechanisms for inter-departmental collaboration. Cross-cutting working groups such as traffic incident management (TIM) teams and multi-disciplinary project development teams have yielded improved coordination among stakeholders.

Successful systematic consideration of operations in the design process typically takes place within an organizational setting in which operations is considered just as crucial as design, construction, and maintenance. Agencies that practice designing for operations well often have a formal policy related to those topics or broad-based, high-level support within the agency. The responsibility for incorporating operations into design cannot fall only on the designers; it must be an agency-driven approach.

The key to integrating planning, design, and operations is for all the players involved to understand their respective levels of focus and to develop tools and mechanisms for communication. Open and regular communication between core members of the project design team and agency management establishes how operational practices will be considered during the design process. High-level support within an agency and a collaborative approach to infrastructure are needed. The personnel who facilitate roadway operations include both transportation agency staff and outside stakeholders, such as transit operators, emergency responders, freight operators, and special event operators. By embracing input from outside stakeholders, a transportation agency can design a facility that enables management and operations, thereby enhancing safety and the overall transportation experience.

In addition to functional silos within an agency or region, other institutional challenges that limit the incorporation of operations into roadway design include a lack of policy or design standards that compel project development staff and designers to account for M&O strategies in infrastructure projects. It is important to note that design personnel at State and local DOTs typically do not act on their own without agency policies or management direction. This reinforces the importance of agency-wide policies and management support in advancing designing for operations. In addition, decisions regarding project goals, scope, and budget constraints are often made well before a project advances into design, so project development staff or supporting contractors should also be highly involved in working to integrate operations considerations into projects from their inception.

1.6.2 Fiscal Impacts of Designing for Operations

Another barrier to operations consideration in design is that when M&O strategies are proposed for inclusion into a roadway infrastructure design, the additional costs to do so may be construed as an unwarranted "accessory." When project costs expand beyond established budgets, operations features such as ITS and emergency responder facilities may be cut because they are deemed non-essential or low priority. However, not fully accounting for operations in design oftentimes results in higher long-term costs. This is especially true in cases where future operational deployments are planned. For example, it is much more cost-effective to place conduit along a corridor where future signalized intersection improvements are planned or construct full-depth shoulders for possible expansion or lane shifts than it is to install these treatments after the primary roadwork is completed. As reported in a recent letter from the U.S. Government Accountability Office regarding the "Dig Once" Executive Order, installing conduit and fiber as a standalone project can cost 15 to 33 percent more than when included in a roadway construction project.16

To maximize the value from an infrastructure investment, transportation agencies must consider the full range of alternatives and full life-cycle cost implications and then implement the most practical solution. Service life and ongoing maintenance costs of the investment must be added to project costs, while also factoring road user and environmental costs. By involving operators in the design process, project designs will better account for agency operations and maintenance resources and expectations. Depending on agency capital and operations funding levels and commitment to meeting equipment maintenance and replacement needs, design treatments for operations could be customized with the appropriate degree of "hardening" or reliability. Ultimately, designs should maximize the benefit-cost ratio over time, and that will likely include M&O strategies with their low cost and high value.

1.6.3 Understanding Management & Operations Needs

Designers and project development staff typically have a thorough understanding of the project development process but have had limited exposure to operational needs. Without experience in the practical application of M&O strategies, designers have no fundamental understanding of how their design may impact roadway operations. As recommended previously, building opportunities for operations, planning, project development, and design staff to regularly collaborate by removing functional silos from organizations will help to increase this understanding.

In addition, design guidance is needed. Through the iterative design process, designers apply appropriate agency design standards, policies, and practices depending on the stage to which the plans have progressed. Design practices typically balance infrastructure needs with project costs and consider finite design elements related to those established in AASHTO's Policy on Geometric Design of Highways and Streets and the Roadside Design Guide.17 To date, an authoritative voice on operational elements to be considered during the design process has not been established or disseminated, which is a challenge to promoting widespread consideration of M&O strategies in design.

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1 Regional Transportation Commission of Southern Nevada, Policy and Procedures Manual, Revised September 13, 2012. Available at: [ Return to note 1. ]

2 Delaware Valley Regional Planning Commission, Overview of the 2011 Congestion Management Process (CMP) Report, May 2011. Available at: [ Return to note 2. ]

3 MAP-21, SEC. 1103. Definitions. [ Return to note 3. ]

4 U.S.DOT FHWA, An Agency Guide on Overcoming Unique Challenges to Localized Congestion Reduction Projects, Sep 2011. Available at: [ Return to note 4. ]

5 Metro, Portland Multimodal Arterial Performance Management Implementation Guidance, Unpublished Draft, 2012. [ Return to note 5. ]

6 Ibid. [ Return to note 6. ]

7 Florida DOT, Transportation Systems Management & Operations, [ Return to note 7. ]

8 National Transportation Operations Coalition, Talking Operations Webinar, Presentation by Elizabeth Birriel, P.E., Florida Department of Transportation, August 2, 2011. Available at: [ Return to note 8. ]

9 Washington State DOT, WSDOT Design Manual, June 2009. Available at: [ Return to note 9. ]

10 Ibid., p. 1110-1. [ Return to note 10. ]

11 Pennsylvania Department of Transportation, PennDOT Publication 646 Intelligent Transportation Systems Design Guide, April 2011. Available at: [ Return to note 11. ]

12 Missouri DOT, Engineering Policy Guide. Available at: [ Return to note 12. ]

13 USDOT RITA, ITS Deployment Tracking Survey Results. Available at: [ Return to note 13. ]

14 AASHTO, A Policy on Geometric Design of Highways and Streets, 6th Edition, 2011. Available at: [ Return to note 14. ]

15 AASHTO, A Guide for Achieving Flexibility in Highway Design, 2004. [ Return to note 15. ]

16 Government Accountability Office (GAO), Planning and Flexibility Are Key to Effectively Deploying Broadband Conduit through Federal Highway Projects. Available at: [ Return to note 16. ]

17 AASHTO, Roadside Design Guide, 4th Edition, 2011. Available at: [ Return to note 17. ]