Practical Highway Design Solutions (2013)

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Practical HigHway Design solutions There are many demands on state departments of transportation (DOTs), from simple maintenance of ever-expanding assets to addressing the increasing mobility and safety needs of all highway users. State DOTs are continuously striving to meet this challenge with lim- ited financial resources. In doing so, some state transportation agencies have adopted design solutions for specific roadway projects at reduced costs, thereby allowing the agencies to address critical needs of the entire roadway system. For example, the Missouri DOT (MoDOT) has initiated a process—labeled Practical Design—that critically reviews projects to establish reduced-cost scope and roadway geometrics based on needs and not standards. They have stated that they want “fewer spots of perfection and more good projects that make a great system.” The Kentucky Transportation Cabinet (KYTC) has approached this program from a somewhat different perspective through their Practical Solutions initiative, where the philosophy of building reduced-cost projects is emphasized using the existing condition as the baseline design and thus achieving a positive outcome with project improvements beyond the existing conditions. As documented in this report, a few other states have adopted similar programs, labeled variously as Practical Design, Practical Solutions, or Practical Improvements. Whatever label is given by the state, the adoption of this cost-saving initiative is increasing and gaining the attention of many other DOTs. The objective of this synthesis is to identify current knowl- edge and practice in the application of Practical Design (the default term used in the report) approaches in roadway project development. Information gathered for this synthesis included the following: • What states have a Practical Design or similar policy. • How states define and implement Practical Design. • Barriers and lessons learned from states that have implemented Practical Design. • Relationship of Practical Design to Context Sensitive Design, Context Sensitive Solutions (CSS), Value Engineering (VE), and other similar initiatives. • How Practical Design differs from the traditional design process. • Modifications to roadway geometric design criteria. • Project-specific roadway design tradeoffs considered. • Cost savings resulting from Practical Design projects. • Performance measures for Practical Design, including safety and operational performance, and system condition. • Liability risk of implementing Practical Design approaches. Information for this synthesis came from published literature, a survey of state DOTs, and interviews with state DOTs identified as having a Practical Design or similar policy. To date the literature is limited for this emerging project development and design philosophy; therefore, relatively little was gained from that review. An online survey was sent to all state DOTs to (1) determine which states have a Practical Design (or other term) policy; (2) become aware of their policy and procedure; (3) identify states that are considering adopting a policy; and (4) determine information states would like to have that would assist them in developing summary

2 or modifying a Practical Design program. The survey achieved an 82% response rate, with 41 of 50 states responding. Follow-up interviews were conducted with those states determined to have a formal Practical Design policy. From the questionnaire, 29 of the 41 responding DOTs indicated that they have a Practical Design (or similar term) policy. These agencies can be grouped into two categories: those that have an explicit, documented Practical Design policy or program and those that have “something similar.” For the former group, the following DOTs are included: Practical Design Missouri, Oregon, Utah Practical Solution Kentucky, Idaho Practical Improvements Kansas MoDOT adopted a formal Practical Design policy in 2005, making it the first state do so. The DOTs of Oregon and Utah also identify their policy as Practical Design. The KYTC and Idaho DOT use the term Practical Solutions. Kansas has adopted Practical Improvements as a title for their similar program. Twenty-three DOTs responded that they have a Practical Design (or similar term) policy. However, they did not have an explicit policy and in their response to other “similar programs,” they referred to context sensitive design or solutions, resurfacing, restoration, and rehabilitation (3R) design criteria, design flexibility, design exceptions, road safety audits, minimum design approach, and other terms. The practices of these states were not examined in this synthesis. The six state DOTs that have an explicit, documented policy are profiled in this report. For each state, how they developed and implemented their policy, how their policy is applied to project development and design, what benefits were derived, and other information sought by states who are considering adopting a policy is discussed. Where examples exemplifying their approach were provided, they are included in the synthesis. A summary of each state’s policy is as provided here: Missouri—MoDOT can lay claim to being the first state to adopt a Practical Design policy, initiating it in 2005. As stated in its implementation guide Practical Design, Meeting Our Customer’s Needs, the goal of Practical Design is to build “good” projects, not “great” projects, to achieve a great system. The key principle is to define the project scope by focusing on achieving the project purpose and need while considering the surroundings of each project. In its implementation guide, MoDOT provides primary design guidance for 29 areas includ- ing type of facility, geometric design elements, pavements, structures, roadside safety, and miscellaneous. The guidelines provided in that document allow for flexibility in the selection of the specific design value. Idaho—The Idaho Transportation Department (ITD) adopted its Practical Solutions/Design (both terms are used) policy in 2007. The program was initiated based on the favorable reports from Missouri. ITD’s philosophy is to build cost-effective projects to achieve a sound, safe, and efficient transportation system. In its guidance document, ITD provides “primary guidance” for several design elements, of which the two primary elements are design speed—which is to be the posted speed or as appropriate to context and intent—and level of service (LOS)—which can be selected at a lower level; for example, LOS D instead of LOS C. The document also provides primary guidance for several other design elements including those related to geometrics, roadside, pavement, structures, bicycle and pedestrian facilities, right-of-way, and even materials and traffic control. Kentucky—KYTC adopted Practical Solutions as its policy in 2008. As with Missouri, the impetus was to find a way to “do more with less.” And as with other states, its underlying principle is to identify the project purpose and need, which drives the project scope. In issuing

3 its Practical Solutions policy, KYTC’s state highway engineer included values for several design elements—pavement and shoulder widths, curve radius, pavement and shoulder cross slopes, grade, stopping sight distance, and passing sight distance—for three classes of roads: two-lane arterials, rural collectors, and rural local roads. The policy also suggests that for two critical factors affecting design—the design speed and the design year traffic volume—lower, in the case of design speed, or nearer, in the case of design year, values can be considered. Kansas—The Kansas DOT (KDOT) adopted a formalized Practical Improvements approach to its projects in 2009. KDOT defines Practical Improvement as “the overarching philosophy which guides our decisions that affect project cost and scope in order to stretch our trans- portation improvement dollars further while still maintaining a safe and efficient highway system.” KDOT issued Practical Improvements, a document that provides guidance on how the Practical Improvement process is to be followed in the development of a project, specifically on developing alternative scopes. In Kansas, projects are initially programmed by the planning department and reach the design office with a general scope and budget, which usually cannot be exceeded. To stay within this budget, proper scoping of the project is considered an integral part of the Practical Improvement process. When applying the Practical Improvement approach, alternative scopes may involve selecting design criteria outside of the prevailing criteria range. Oregon—The Oregon DOT (ODOT) issued its Practical Design policy in 2010 after being mandated by the state legislature in its Jobs & Transportation Act of 2009. ODOT was to follow design practices that incorporate the maximum flexibility in the application of standards to reduce cost while preserving and enhancing safety and mobility. ODOT, in its Practical Design Guidebook, presents a process for applying Practical Design; it does not provide specific design values. Design flexibility is the hallmark of its process and is guided by three overarching goals: 1. To direct available dollars toward activities and projects that optimize the highway system as a whole. 2. Develop solutions to address the purpose and need identified for each project. 3. Design projects that make the system better, address changing needs, and/or maintain current functionality by meeting, but not necessarily exceeding, the defined project purpose, and need and project goals. Utah—With the issuance of its Practical Design Guide in 2011, Utah is the most recent state to adopt a Practical Design policy. The Utah DOT (UDOT) has not developed different design criteria; rather, it offers general guidelines for implementing Practical Design. For UDOT, the most critical element in Practical Design improvement projects is the project’s objective statement. Practical Design is a “design up” approach, not a “strip down” process; meaning, rather than starting with the desired level of improvement and removing items until they meet the budget, project teams are advised to look at the existing conditions and design improvements that meet the project’s objective statement. A key aspect of its program is design flexibility and the use of design exceptions, which can be implemented when either of the following applies: • The design standard exceeds the objective statement or • A lower cost solution not meeting design standards is identified that does not compromise safety. Other key findings of the study include the following: • The Practical Design approach does not appear to apply explicitly to 3R projects. Each of the six states profiled has a separate 3R policy for guidance for those projects. However, it is noted that 3R projects are not typically improved to full standards, which makes 3R and Practical Design-based projects similar.

4 • For the six states that were profiled, most recognize a relationship and similarity in the principles of CSS and Practical Design. For instance, Kansas stated that both CSS and Practical Design apply flexibility in the application of design features. Oregon views its Practical Design policy as the next logical step to CSS. Utah views its Practical Solutions policy as combining elements of CSS and VE. Practical Design seeks an economical solution for individual projects, focusing on the projects’ purpose and need. CSS seeks a solution that addresses the needs of multiple users and functions of the facility, which sometimes can lead to added costs. • Practical Design is not the same as VE, although here too there are similar goals. VE, which is usually reserved for large-scale projects, is a method to determine the most cost-effective way to achieve proposed improvements. Practical Design is a method to determine the most cost-effective way to achieve the projects’ purpose and need. The tools and procedures used for VE can be used for Practical Design. • Design exceptions are frequently used as part of the Practical Design process in most states that have adopted this policy. When a value for a design element is chosen that is less than what would be required by its design manual, design exceptions are required by the states. Practical Design has emerged as a project development and design program that seeks to develop individual projects with improved safety and operation but at a reduced cost, using the savings for more projects within a fiscal budget. For all states that have adopted this policy, the driving force was to maximize the use of available transportation funds, which were becoming limited and less able to meet all of the many system needs. There are numerous ways to describe Practical Design and similar policies. One would be a project development and design philosophy whereby projects are scoped to be “right-sized” to meet the project purpose and need, avoiding the desire to arbitrarily bring the facility up to a maximum level for all design elements. Practical Design does not apply to just geometric design elements. It can be all-encompassing, ranging from deciding during planning and scoping phases on the type of facility to meet the purpose and need; to the selection of design volumes, design speed, and specific design elements; and even to the selection of pavement material and thickness.