According to the Federal Highway Administration (FHWA), Performance Based Practical Design (PBPD) is a performance management framework “focused on scoping projects to stay within their core purpose and need.” PBPD is applied as a decision–making approach that relies on quantitative analyses to guide decision-making throughout the project development process resulting in a better system performance. This practice has been a consistent method of project delivery for Departments of Transportation (DOTs) across the United States as agencies aim to provide a level of discipline to eliminate nonessential project design elements, lower costs and improve the value of projects.
Enhancing What’s Already in Place
The Arizona Department of Transportation (ADOT) advertises dozens of infrastructure projects yearly as a part of their Five-Year Construction Program. ADOT has traditionally maintained guidance for consulting firms and partners focused on value engineering, asset management, design exceptions and purpose and need statements. However, with budget constraints and the need to improve the efficiency of construction dollars spent on infrastructure projects across their network, ADOT pushed to implement PBPD in all future projects. In March of 2019, ADOT published their Guiding Principles for Performance Based Practical Design. As an update to these guiding principles, ADOT is partnering with B&N to support PBPD program development and integration.
PBPD Program Development
B&N is developing ADOT’s guidance for the implementation of PBPD in the Department's Project Delivery Process (planning, design and delivery) that is based on the Department’s Guiding Principles for PBPD and the industry’s best practices related to PBPD. To do this, B&N has implemented a three-pronged approach:
- Conduct a PBPD Peer Collaboration Workshop
- Facilitate a PBPD Mission Workshop
- Establish a PBPD Guidelines Working Group
B&N coordinated a remote Peer Collaboration Workshop with FHWA and peer agencies that have successfully implemented robust PBPD programs. This workshop included engineers from Ohio, Minnesota and Washington State DOTs who shared their experience in applying PBPD with B&N and ADOT. Then, ADOT leaders and B&N staff conducted a PBPD Mission Workshop to establish the ground rules, goals and metrics for an ADOT PBPD program. From this Mission Workshop, B&N established a working group of staff from ADOT’s divisions and technical groups to develop the PBPD Guidelines. Feedback from this Working Group has been vital in tailoring a guide to create an effective PBPD program that meets ADOT’s needs and is streamlined into their existing project development processes.
The PBPD Guidelines document will be submitted to the working group and a review summit will be held. After the summit, the PBPD Guidelines will be finalized for implementation, which will consist of staff training and promoting the use of PBPD.
Design Decisions for an Improved System
Done correctly, PBPD can yield cost savings and improved system performance. PBPD is not intended to replace existing design standards or project development processes; it provides flexibility and encourages the project team to diligently evaluate design decisions and alternatives. ADOT believes the PBPD approach will help ensure that designs meet the project’s objectives and needs, resulting in the optimal performance of the roadway system. Focusing on the overall system performance, PBPD helps agencies better manage their transportation investments and serve system-level needs and performance priorities with the limited resources they have. As such, ADOT intends PBPD to be incorporated into the project development process for projects to come in the near future.