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White Papers for Right-Sizing Transportation Investments (2020)

Chapter: 4. Right-Sizing Project Design

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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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Suggested Citation:"4. Right-Sizing Project Design." National Academies of Sciences, Engineering, and Medicine. 2020. White Papers for Right-Sizing Transportation Investments. Washington, DC: The National Academies Press. doi: 10.17226/25920.
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69 White Papers for Right-Sizing Transportation Investments 4. Right-Sizing Project Design 4.1. Introduction This white paper addresses the topic of right-sizing through a series of reflections on the paradigms, tools, and approaches that that contribute design-level project outcomes. The paper addresses the question, “How does an agency arrive at the most efficient project scope and functional design representing the appropriate size, composition, and extent of a transportation facility in a situation where the need for the infrastructure either has significantly changed since the facility was originally built, or is anticipated to change significantly during the project life?” 4.2. Highway Design Paradigms and Right-Sizing Review of Design Paradigms  The term “design” is used here to include: (1) functional design, which establishes broad design elements (e.g., fully-controlled freeway vs at-grade intersections type road), general alignment (for a new road) or realignment, user (vehicles, pedestrians, bicyclist) design parameters, and the like; (2) preliminary design, which establishes more specific design elements, such as cross- section, design speed, etc.; and (3) final design, used for construction. NCHRP Report 839, A Performance-Based Highway Geometric Design Process,48 chronicles 10 alternative design paradigms or concepts that have become part of design practice. Those that would seem to be integral to Right-sizing transportation investment are enumerated below with their stated goals:  The complete streets concept focuses on creating roadways and related infrastructure that provides safe travel for all users. Its stated goal is to consider all transportation modes in the design of urban and suburban arterials, with explicit consideration of bicycle and pedestrian needs. (More information on this concept can be found at https://smartgrowthamerica.org/program/national-complete-streets-coalition/)  The context-sensitive design (aka solutions) concept places priority on assuring that highway projects fit the context of the area through which they pass, puts project needs as well as the values of the highway agency and community on a level playing field, and considers all trade-offs in the decision making. Its stated goal is to assure that each 48 T. R. Neuman, R. C. Coakley, S. Panguluri, and D. W. Harwood. NCHRP Report 839: A Performance- Based Highway Geometric Design Process, Transportation Research Board, 2017. 4

70 White Papers for Right-Sizing Transportation Investments project is designed in a manner consistent with the context of the roadway, advocating strong consideration of community, neighborhood, and environmental values. (More information on this concept can be found at http://www.ite.org/css/)  The concept of practical design focuses on addressing only those improvements that are needed ‒ to fulfill the purpose and need statement ‒ and eliminating those improvements that are not absolutely essential, thereby reducing the overall cost of a project, with savings made available more projects within a fiscal budget. The stated goal of practical design is, where appropriate, to relax design criteria, within the allowances of design flexibility, to minimize project costs, consistent with achieving other stated goals. (More information on practical design can be found at http://www.trb.org/Publications/Blurbs/168619.aspx)  The concept of performance-based design incorporates a design process that explicitly considers performance measures, typically those related to operations and safety, in the decision-making process. (More information on PBPD can be found at https://www.fhwa.dot.gov/design/pbpd/)  The concept of value engineering is a systematic process of project review and analysis by multi-disciplinary team to provide recommendations for improving the value and quality of the project. The goal is to improve the project value (as determined by defined criteria) by modifying any aspect of the design that would result in an increase in value. Value engineering has goals similar to practical design seeking the same (or better) project performance at lower cost, but also better project performance, even at somewhat higher costs. (More information VE can be found at https://www.fhwa.dot.gov/ve/)  The concept of Designing for Resurfacing, Restoration, and Rehabilitation includes a set of geometric design criteria for 3R projects that are less restrictive than those used for new construction and reconstruction. This design guideline is an example of practical design and the application of design flexibility, based on risk assessment, that seeks to achieve equal (or, at least acceptable) performance to that achieved by full AASHTO Green Book design criteria at lower cost.  The concept of Designing for Very Low-volume Local Roads (≤ 400 ADT) recognizes that very low-volume local roads represent a different design environment than higher-volume roads. Similar to 3R project design, it too applies design flexibility commensurate to the risk assessment. While these alternative design paradigms are labeled in NCHRP 839 as “concepts,” they are more appropriately labeled as approaches, as they are indeed being followed by states in their project development. The Importance of Project Purpose and Need  A “prime mover” of any transportation project is the Purpose and Need statement, as it defines the transportation deficiency or problem ‒ the Need ‒ and the set of objectives that will be met to address the deficiency ‒ the Purpose. (While the “need” is defined first, the “purpose and need” phrase is the terminology most commonly seen in statues and regulations, and it is more

71 White Papers for Right-Sizing Transportation Investments commonly used in case law, guidance, and general practice.) The project Purpose and Need statement drives the process for alternative consideration, in-depth analysis and ultimate selection. For projects requiring an environmental impact statement, it is required, and even if not, it should be publicly stated. Furthermore, it should be developed in concert with stakeholders as early as possible during the project planning phase and, if need be, modified based on more current data and citizen input up through the final design. The need for the project can be some deficiency related to safety, congestion, level of service, connectivity, access, pedestrian/bicyclist accommodations, or other conditions. It could also be recognition of a change in user characteristics, land use, or other conditions that are no longer served by the existing road facility. The purposes (or often stated as objectives) are design options that address these needs to varying solution levels. These design options could be considered right-sizing alternatives ‒ developing the project to meet changing needs. From a highway design perspective, right-sizing alternatives can cover the gamut of design plans from simple, relatively low-cost projects, to multi-year, multi-faceted and consequently expensive projects. A relatively low-cost project could be a so-called road diet for a road section whereby the cross section is reset to accommodate pedestrian and/or bicycle users to reflect a change (increase) in non-motorist user demand ‒ a right-sizing scenario. (See Table 11 below on the IOWA DOT program for Statewide Lane Reconfiguration for one state’s approach to identifying candidate sites for such a program.) An example of a higher-cost project would be the ‘right- sizing’ of Buford Highway just outside of Atlanta, GA. As profiled by Duncan and Morris49, the entire corridor was re-purposed with design features such as paved sidewalks on both sides, count-down signals at intersections, signalized mid-block crossings and overhead and pedestrian lighting. Table 11 Example: Iowa DOT Statewide Lane Configuration Screening The IOWA DOT is embarking on a program to identify sites with the potential for lane reconfiguration from a four- to three-lane ‒ an example of a road diet. In the example illustrated below, one of the travel lanes is removed allowing for a reconfiguration of the cross section for other modes, i.e., pedestrians and/or bicyclists. 49 Duncan, C. and A. Morris. From Preservation to Adaptation: Right Sizing as an Investment Strategy. TR News No. 309, May‒June 2017.

72 White Papers for Right-Sizing Transportation Investments The DOT has found that reallocation of the space in the right locations can increase the safety and operation of the corridor, and, provide local agencies an opportunity to grow their network of bike and pedestrian infrastructure and align with existing complete streets. Within the DOT’s business process, a number of factors are usually considered to determine the feasibility of converting a four-lane roadway to a three-lane roadway, those being:  Roadway function and environment  Overall traffic volume  Level of operational service  Turning volumes and patterns  Frequent-stop and/or slow-moving vehicles  Weaving, speed and queues  Crash types and patterns  Pedestrian and bike activity  Right-of-way availability, cost and acquisition impacts  General characteristics: parallel roadways, offset minor street intersections, parallel parking, corner radii, and at-grade railroad crossings.1 These factors are usually analyzed at a corridor level and require significant data gathering and analysis to determine feasibility. Iowa DOT concluded that such an analysis was impractical to perform at a statewide level, and so developed a more streamlined approach to identify potential sites. The approach leans heavily on the use of existing roadway data bases and geographic information systems for screening. The implemented approach was as follows:  Querying of Data: “identify all roadway segments within the state that had four through lanes, no median, and were open to two-way traffic”  Filtering and Calculations: Exclude segments with an AADT above 18,000 and classify remaining segments into three tiers, by volume: Low (0-6,000 AADT), Medium (6,000-

73 White Papers for Right-Sizing Transportation Investments 12,000), and High (12,000-18,000). Additionally, calculate access density for each link (summation of business and private entrances, divided by length), and identify all signalized intersections within 1/8th mile of each other.  Geoprocessing and Aggregation: Aggregate continuous corridors to a minimum length of ½ mile. Exclude any shorter corridors from analysis. Then, calculate an aggregated corridor-level crash rate and “obtain the total number of severe injuries for each potential candidate site.”  Quality Control: Visual inspection and manual corrections to address any discontinuous corridors or other improperly selected segments. Iowa DOT applied this approach to both urban and rural road segments, ½ mile or greater in length, including those owned by both the state and local governments. The result was a set of 223 candidates, groups into High (72), Medium (99), and Low (52) volume groups. The data set has not as of yet been analyzed, but was constructed to include key variables that can help in identifying more likely candidates for lane reductions, namely:  AADT.  Access Density: “Four-lane corridors with higher access densities stand to benefit the most from a conversion to three lanes. A greater number of accesses results in a greater number of left turns. The addition of a continuous center turn-lane provides a safer means of accommodating left-turning vehicles by separating them from the through traffic.”  Signalized Intersections: Corridors with at least one signalized intersection were flagged to indicate that “at traffic flow in the three-lane configuration may be enhanced through a more in-depth analysis of signal operations.”  Crash Rate: “Reducing the number of lanes from four to three can have a substantial effect on the number of crashes on a roadway.” Source: Iowa DOT. Statewide Screening for Potential Lane Reconfiguration.  https://iowadot.gov/systems_planning/pr_guide/Safety/StatewideScreeningforPotentialLaneReconfiguration. pdf   Connecting Design Paradigms to Right‐Sizing  Each of the design approaches has relevancy to right-sizing, as defined for this project as “… fundamentally changing the size, composition, and extent of the transportation system from would it would otherwise be to arrive at a more efficient use of resources than would otherwise be the case.” There are a few commonalities across these approaches that are instructive for an agency considering how to incorporate “right-sizing” into their design practice. First, it is notable that the application of these alternative design concepts oftentimes requires the use of “design flexibility.” As stated in NCHRP 839, “In practical terms, design flexibility means that designers have choices not mandates. Choices relate to the level of transportation service provided for all modes, the inclusion or exclusion of specific features (e.g., lanes by type and usage, medians by type, on-street parking), treatments (intersections versus roundabouts, types of intersections, types of interchanges), and dimensions for each element.” In choosing how to implement

74 White Papers for Right-Sizing Transportation Investments flexibility, a designer should select features that are compatible with the project “purpose and need,” and developed under a performance-based practical design process, meaning that an analysis should be made of the impacts of primary design elements using measures of safety, operations, access and other criteria established by the agency and stakeholders. It is also worth noting from these design approaches that certain aspects of a right-sizing mindset can be set up so as to become “standard operating procedure.” Interviews conducted with KDOT in support of this white paper, in addition to interviews with five other states conducting during the preparation of NCHRP Synthesis 443, Practical Highway Design Solutions, found this to be the case. Through these approaches, states are designing projects to meet the project “purpose and need” clearly developed with input from stakeholders ‒ partner agencies, local agencies, and the public. In so doing, they are developing design options that satisfy the objectives and not to a standard design. They feel this is “right-sizing.” 4.3. Design, Development, and Infrastructure Burdens: The Big Picture The population base in some regions is growing very rapidly, while other regions have almost no growth, and sometimes negative growth. Yet one thing is common among nearly all urban areas – their urban footprint and aggregate infrastructure keep growing whether their population is growing or not. That’s a problem for funding long-term maintenance. Why do regions with negative population growth continue to expand their urban footprint? One major reason is that as yester-year’s “new and shiny” land uses and infrastructure deteriorate, businesses and residents sense the downward trajectory, and those with the means often move to the next “new and shiny” greenfield development. Thus, the areas they fled will deteriorate even faster, because there is even less tax base for maintaining everything. Thus, the big-picture design and development problem to be solved by right-sizing efforts includes several angles: 1. Help emergent greenfields right-size the first time. 2. Looking beyond “size,” foster resilient design in greenfields that will not be abandoned by adjacent uses, but instead will retain and increase the tax base that supports it. 3. Create retrofit strategies for corridors and areas that have deteriorated, so that the infrastructure they already have can compete anew for investment that would otherwise expand the infrastructure burden at the fringes. 4.4. Right-Sizing for Greenfields: Getting it Right the First Time Today’s problems are easy to see and tend to consume a large proportion of resources in discerning the root causes and devising effective remedies. Nevertheless, in any location where

75 White Papers for Right-Sizing Transportation Investments greenfields are urbanizing, it is essential to apply best practices, and thereby solve tomorrow’s problems, before they become problems. In many rapidly-growing areas, there is often pressure to pursue “greenfield” development. Such development usually occurs on undeveloped parcels not surrounded by existing development, or on large parcels surrounding partially developed areas or undeveloped areas.50 In metropolitan areas, greenfields available for development are frequently located on the outer fringes of the existing urbanized area. Such developments often require significant investment in roadways and other transportation infrastructure to support the mobility needs of their residents and businesses. To right-size greenfield development, it is important for communities to understand that how they structure their background land uses and network connectivity will ultimately dictate the multimodal needs of the macro-level arterial network. Understanding the Implications of Road Network Configurations  In the early 1990s, the Institute of Transportation Engineers (ITE) published a useful guideline that recommended ideal network spacing of a modest-sized freeway every five miles, a principal arterial every two miles, a minor arterial every one mile, and a collector street at least every half- mile.51 Salt Lake County, Utah applied that recommendation as part of a network analysis and arterial best practices effort to compare what they have, existing and planned, with that ITE guidance. The resulting “Scottish plaid pattern,” shown in Figure 15 is becoming iconic ‒ used in presentations by MPO staff, UDOT, Envision Utah, and others to drive home the message that congestion exists largely because drivers have relatively few options. 50 Davidson M. and F. Dolnick, ed. “A Planner’s Dictionary,” American Planning Association, Planning Advisory Service Report Number 521/522, p. 206. 51 https://www.ite.org/css/online/DWUT03.html.

76 White Papers for Right-Sizing Transportation Investments Figure 15 "Ideal Network" vs. Actual Salt Lake County Network Source: Metro Analytics  Not surprisingly, throughways in the sparse areas are overwhelmed with congestion, serving long- distance freight and commutes, while also serving local trips, such as shuttling kids to soccer games. They are also in high demand as bikeways and transitways ‒ because they are the only pathway these modes have available. One can debate the merits of so many freeways, but clearly the more extensive the arterial/collector system is, the more able it is to support alternative modes and evolving uses, and the less pressure there is for more and wider freeways. “Right-sizing” in many communities often means downsizing under-utilized pavement in order to upsize other uses. But in cases where through streets are infrequent, right-sizing could mean a certain type of upsizing for all modes. Communities in Utah are getting the message and starting to revamp plans for remaining greenfields to show more collector and arterial streets where still feasible. Figure 16 shows five common types of development. At one end is the tight-grid pattern, which dominated the American landscape prior to WW2, and is resurgent again, often as a curvilinear grid, within many New Urbanist planned communities. When most streets are through streets, arterials and collectors can often do fine with just one through-lane each direction, and can also accommodate on-street parking, lower speeds, etc. It is also possible to accommodate bikes, transit, and other needs on parallel streets ‒ because there indeed are parallel streets.

77 White Papers for Right-Sizing Transportation Investments Figure 16 Comparison of development road network configurations Source: StreetPlan.net  At the other end of the spectrum are suburban “super-grids” and more haphazard networks. Super-grids are common where farm access roads along USGS section-lines became the default “plan” for urban arterials, and everything in between was left to individual developers, who historically derived their maximum value with cul-de-sacs and discontinuous streets. The arterials that define super-grids become all-important, to all modes and most businesses, because they are the only streets available. Land uses along such arterials tend to degrade over decades but might be stabilized with certain techniques that can protect land values. In general, the tighter the grid, the more adaptable the area is to changing conditions. However, there are still a great many greenfield areas emerging or likely to emerge with super-grids, and communities that want to or will emerge this way need to understand that right-sizing in these cases could mean protecting much larger right-of-way footprints, and/or more alignments, than their normal practice would dictate, in part for multimodal uses that have no other location available. Starting from the top-level “Scottish Plaid,” zooming in to the next level can be insightful. While Census-defined blocks are of course much smaller, the “travel shed” to streets that have potential for trips of one mile or more can become extremely large.

78 White Papers for Right-Sizing Transportation Investments Figure 17 displays a selection of streets in Salt Lake County. Near downtown, South Temple divides the “Avenues” district, which has three-acre blocks, from the rest of downtown which has famously large 10-acre blocks. (For comparison, Portland, Oregon has 200-ft, one-acre blocks). The image also shows a square-mile selection with “300-acre blocks” in West Jordan, very typical of its area. While Census-defined blocks are of course much smaller, the “travel shed” to streets that have potential for trips of one mile or more can become extremely large. Figure 17 Salt Lake County Network and One-mile Square Area of Downtown Salt Lake City Source: Metro Analytics  Grid-Spacing and Right-of-Way Usage Analysis. Figure 18 provides a spacing and right-of-way usage analysis of the above areas. Row 4 shows the Avenues have 13 grid streets per mile of width, and Row 6 shows accumulated pavement width of 590 feet (used for parking as well as traffic). Salt Lake’s 10-acre blocks result in seven grid streets per mile of width, but most streets also have two lanes each direction, for an accumulated pavement total of 390 feet. Daybreak is a large New Urbanist planned Community currently under development, with blocks very similar to Downtown Salt Lake. The suburbs that emerged between WW2 and 2000 more typically have just 1.7 grid streets per mile of width, and a paltry 120 feet of accumulated pavement. Row 8 shows the urban density pattern that can be easily supported by the grid style. While the Avenues are not a “CBD,” the grid underlying it can easily support CDB-like densities. Salt Lake’s 10-acre blocks started out at less-than-suburban densities and are now supporting it’s CBD. However, it is not an ideal grid for supporting double or triple its current density. And finally, the suburban grid can often be inadequate even for suburban densities, and traffic/multimodal management can be extremely challenging when the market wants to or starts to increase those densities. When comparing Row 5 with 1,000 feet of through-street right-of-way per mile on one end, vs 150 feet on the other end, it might appear the suburban model is more efficient because it involves less overall infrastructure and therefore less maintenance. But that is not necessarily the case, as there could easily be the equivalent of 1,000 feet or more of pavement

79 White Papers for Right-Sizing Transportation Investments accumulated on windy, dendritic interior streets. The difference is that dendritic streets offer very little utility to alternative modes or to drive trips much beyond half a mile. Figure 18 Analysis of Spacing and Right-of-Way in Various Salt Lake County Environments Source: Metro Analytics  Corridor‐Level Best‐Practice Patterns  Ideally, new greenfield development would have tight local grids. But regardless of how the background grid may emerge, odds are most communities will create multi-lane arterial streets that will eventually carry 20,000 vehicles per day or more. Such arterials will continue to attract and be zoned for commercial and multi-family uses. A major problem with similar arterials from the 1950s through today is that development along them has only had access from the fronting arterial. Figure 19 below highlights the disjointed, dendritic background streets traced from a real place. Figure 19 Illustrative Example: Disjointed Access Along an Arterial Source: Metro Analytics  A community would do well to protect its arterial streets more than this. For example, if they also had back-side access, as highlighted in yellow below (Figure 20) it would greatly relieve the

80 White Papers for Right-Sizing Transportation Investments arterial and create flexibility for the future. Developers could have flexibility in the curvilinear nature of these back-side streets. Continuity is the key. When such streets meet with other arterials, perhaps right-in/right-out access would be required until signals are warranted. This pattern does not necessarily require any additional pavement beyond the previous. It just arranges it in a way that improves local circulation and creates a buffer between arterial uses and neighborhood uses. Figure 20 Illustrative Example: Front and Back-side Access to Relieve Arterials Source: Metro Analytics  The next graphic zooms out to show how a square-mile of the above pattern might look. More significant arterials would be flanked with parallel backage roads, while interior collectors need not be. The crossing of significant arterials creates a grid for localized circulation at what is likely to be a significant activity node. Figure 21 Illustrative Example – Arterials with Backage Roads, Broader View Source: Metro Analytics 

81 White Papers for Right-Sizing Transportation Investments Summary of Right‐Sizing for Greenfields   Adopt a minimum standard for continuous streets, ideally ¼ mile to ½ mile.  Avoid rigid right-of-way standards such as “84 feet for minor arterials, and 110 feet for principal arterials.” Instead evaluate each street within its network context, desired use typology, and include Complete Street elements from the beginning, or have a plan for including them later.  If your grid is defaulting to Haphazard or Suburban Super-Grid, encourage flexible, adaptable design techniques, such as continuous backage roads along the arterial, and innovative intersection designs, discussed in later sections. 4.5. Identifying Opportunities to Right-Size Existing Streets Every right-of-way, when first built, was judged to be “right” by stakeholders for its time and context. So, what kind of changes in context can turn a right street into a wrong street? How can we tell when the reasons to “right-size” start to outweigh the reasons not to? There are several analysis techniques that can help. These include traffic volume analysis, safety analysis, modal demand analysis, trip length analysis, and tax-base analysis, as discussed in the next sections. Volume Analysis  A big part of the opportunity for change lies in identifying streets with excess capacity. There are cases where a major highway was effectively replaced by a nearby freeway, or where a once- popular auto-oriented corridor is no longer popular, as reflected in roadway volumes as well as tax-base analysis, and rejuvenation could depend on reorganizing right-of-way. Whatever the case, understanding critical volume thresholds is helpful. Table 12 depicts rule-of-thumb traffic volumes at which each facility-type tends to show signs of distress. As an example of how to use this, there are many cases where seven-lane highways popular decades ago currently carry 25,000-35,000 vehicles per day, yet they could easily support up to 55,000 per day. In many cases, it would be easy to convert a lane to Bus-Rapid Transit, or just reorganize to allow on- street parking or other features that can aid community objectives for livability and economic revitalization.

82 White Papers for Right-Sizing Transportation Investments Table 12 Rule-of-Thumb Traffic Volumes at Which Facilities Tend to Show Signs of Distress Source: Metro Analytics, derived from Florida‐based research and microsimulation assuming 10% of AWDT  occurs in PM peak hour.  As another example, suppose a four-lane arterial (no center-turn lane) currently carries 22,000 ‒ well below its 28,000 ability ‒ but a “road diet” to change it to three lanes could result in significant congestion, as three-lane highways are challenged much above 20,000. Since it is close to the margin, it may well work if you can account for what will happen to the extra volume that won’t fit easily. Are there parallel paths that could absorb some spill-over? Since capacity is usually constrained by intersections, would roundabouts or other high-efficiency designs help boost a three-lane section to carry 22,000 or higher? Would multimodal improvements enabled by the change attract enough away? If the change facilitates mixed uses, would the mixed uses that emerge over 10-20 years result in shorter drives and more use of alternative modes that the street will operate better in the long run than it might in the near term? And lastly, these need not be red-lines. Even if the change may cause an uncongested road to become noticeably more congested, maybe that doesn’t matter much to stakeholders in light of the benefits obtained for other goals and objectives. Safety Analysis  As exurbs transitioned to suburbs, the rural highways that connected them suburbanized. Because speeds had been high before, there is usually an effort to maintain speeds as high as possible, so “right-sizing” at the time of first transition often means access control and signal spacing every half-mile or more, combined with additional lanes and speed limits of 40-50 mph. But regardless of design features, a 40-50 mph arterial will see conflict hot-spots emerge. In the beginning, these are often car-on-car accidents, but as the area intensifies, or sees demographic changes that include high shares of citizens dependent on walking or biking, then accidents can skyrocket, and the societal costs of accidents can begin to exceed the societal benefit of time saved at 45 mph vs 35 mph. Safety analysis need not always wait for evidence of a problem to influence decisions. For example, an arterial may not yet have an apparent pedestrian safety problem, because adjacent uses are heavily auto-oriented, or blighted and inactive. If uses are ripe for redevelopment, and if

83 White Papers for Right-Sizing Transportation Investments the community is encouraging a mix of uses at higher intensities than before, then it is easily predictable that a 45 mph highway will result in serious accidents if such uses materialize. However, it is also possible that a decision not to change the typology to a 30-35 mph design will impede the market for the community’s land-use desires, and hence there will continue to be no apparent pedestrian safety problem because there remain few pedestrians. This is a matter of trade-offs between speed for drivers vs. other performance objectives that each situation must assess in any right-sizing debate. However, it may be possible to achieve win-win through design that reduces maximum speed without inhibiting average traverse speeds, in part through use of alternative, innovative intersection design strategies, discussed later. Modal Demand Analysis / Trip Length Analysis  As localities change, the nature of trips starts to change, and there may also be significant latent demand for alternative modes. An area may well have more cyclists and pedestrians than before, but if it is a tiny share of the total it can be easy to dismiss as irrelevant compared to the traditional task of unimpeded vehicular flow. Taking bikes as an example, surveys frequently suggest that while biking often represents less than 5% of a corridor’s overall volume, as many as 60% of respondents say they would bike regularly for recreation, exercise, commuting, and small errands if they felt protected from high-speed traffic. Communities that have invested heavily in such safety do in fact tend to see “build it and they will come” results that help justify the projects in retrospect. To help determine how many may be eligible for active modes, it is useful to evaluate the likely trip lengths associated with emergent uses. The illustration in Figure 22 depicts two arterials, each with 30,000 vehicles per day. If the top has a bedroom community anchoring one end, an employment center on the other, and relatively little between, then the 30,000 trips on the arterial will be heavily weighted toward long-distance trips, and arguably “right-size” in this context could skew toward helping this majority traverse long distances quickly. In the other case, say there are a significant mix of commercial and residential generators all along the path. At any point on the path there may still be 30,000, but much of that total is using the corridor only for a short distance, and thereby will be only minorly affected by speed changes. In the top case, installing premium features for active modes may attract relatively few patrons, because the overall length of typical trips is too far to walk or bike regardless. In the bottom case, a huge share of trips are short, and thereby likely to respond to premium treatment of active modes. However, without this analysis, it could appear to traffic engineers that nothing has changed, and therefore they conclude it is best to leave the street at high speeds, assuming the majority are on long trips and will therefore value high-speed travel. Corridors with high shares of turning movements and increasingly high densities and usage types are good indicators that there may be significant latent demand that would respond positively to a new arterial context.

84 White Papers for Right-Sizing Transportation Investments Another interesting angle to trip length analysis is that 30,000 could be 30,000 ‒ or it could be 60,000. In the top example, if all 30,000 trips go from one anchor to the other, then there are truly 30,000 unique trips. In the bottom example, notice each unique path has 10,000 vehicles, and there are six unique paths. Thus, there are 60,000 actual vehicles utilizing the corridor, although just 30,000 can be counted at any given point. This means an increase in corridor trip generation due to more intense uses does not necessarily mean traffic along the corridor will increase much, if at all. Figure 22 Illustrative example: how trip length relates to right-sizing opportunities Source: Metro Analytics  Tax‐base Analysis  One of the most relevant topics in right-sizing is the effort to avoid getting caught with more infrastructure than the economy can afford to maintain. In that context, it is helpful to see districts that create more tax revenues than the same areas cost to maintain, vs districts that cost more in the long run than they generate. For example, a community may imagine that an ocean of big-box retail will be a financial boon, and each huge parcel will create more revenue than any small parcel, but in aggregate, the small parcels often create more revenue with less overall infrastructure burden.

85 White Papers for Right-Sizing Transportation Investments Figure 23 Illustrative comparison of development and taxes generated Source: Urban3 and Strong Towns  In Figure 24, green areas are revenue positive, while red are revenue negative in a lifecycle analysis. Notice that in this case it’s the lower-income neighborhoods that are generating more revenue relative to their infrastructure burden, most likely because it is higher density. Some of the larger, lower-density parcels are also the most costly in the long run, despite being in affluent areas. Figure 24 Illustrative tax base analysis Source: Urban3 

86 White Papers for Right-Sizing Transportation Investments 4.6. What Does Right-Sizing Look Like? All of the previous analysis techniques can help identify when an existing or proposed design is “wrong” for the situation – or not a good fit for the emerging context. But what can you actually do to make it right? What elements will the final product have that will help property owners, active mode groups, city officials, engineers, and taxpayer watchdogs to all agree that the new plan is “right” for the emerging context? There are many angles to answering those questions, but popular focal-point is the typical cross section of the street. The Institute of Transportation Engineers recently combined with the Congress for New Urbanism to produce a joint ITE/CNU best-practice guide called “Designing Walkable Urban Thoroughfares.” The guide includes a wide array of walkable design techniques, but it also includes design criteria for a wide spectrum of contexts, from rural to suburban to heavily urban. The next section discusses hypothetical stakeholder processes that seeks to change an existing “wrong street” into something they can all agree makes more sense within a budget they can justify. Illustrative Right‐Sizing Example (Downsizing)  Design Responding to Changing Development Context  Figure 25 follows a hypothetical right-sizing evolution where a stakeholder’s group interacts with engineers to arrive at a project they can all agree on. The top image is existing conditions, the middle represents the community’s first iteration, which traffic engineers in this case find unacceptable, and the last image becomes acceptable to traffic engineers due to the introduction of high-efficiency Alterative Intersections. Imagine the story unfolds as follows: Suppose a stakeholders group convenes for a corridor study, and uses an interactive visualization platform to sketch their existing conditions, and several alternatives until they arrive at their preferred alternative. Their “existing conditions” (the top image in Figure 25 below) are very typical of many large suburban intersections, with two through lanes, double-left lanes, and right-turn pockets. The overall space is 125 feet, but the pavement for managing traffic is 101 ft, which leaves just 12-feet on each side for a modest sidewalk and a buffer strip. Such a highway may be appropriate for many suburban contexts, with 45 mph travel. However, this group would like a Complete Street design to improve walking and biking and to encourage new mixed-use economic development. Engineers review “Designing Walkable Urban Thoroughfares,” published by the Institute of Traffic Engineers, and conclude that for the desired mixed-use context existing lanes and speed limits are excessive (hence labeled as red in the top). Instead, 10-11 foot lanes are recommended (green in the middle cross section). Because lanes are narrower for the new context, that creates opportunity to expand other uses of the right-of-way. Stakeholders also want to narrow the median to just one left turn pocket, to expand the pedestrian realm even more.

87 White Papers for Right-Sizing Transportation Investments Many stakeholders are also pushing for speeds as low as 30 mph. However, the senior engineer in the room pushes back, noting this is still a congested corridor despite having lost much business, and downsizing to just one left-pocket, as well as a speed reduction from 45 to 30 mph, is simply unacceptable. Their analysis shows that to do so would reduce the average peak hour speed from today’s 17 mph to just 10 mph. Win‐win with Place‐Making Alternative Intersections  Later, a junior engineer who attended the meeting informs his boss of some new alternative intersection techniques he heard of in college for rerouting left turns, with a likely result that traffic will flow better than before, because lefts are routed elsewhere. His boss asks him to simulate traffic under all three concepts, and together they conclude that not only can they accommodate stakeholder desires to reduce the median width, but they can also entirely remove lefts from the critical sections. Now stakeholders can have a planted median with a pedestrian refuge at the crosswalk (Figure 26). And because the technique reduces delay, they inform stakeholders they can now accept the 30-mph design speed for a few blocks just, and still get traffic through slightly faster than even the current double-left design. Stakeholders are elated by the news, but are cautioned that there may yet be many reasons why the proposal will not work. But at least now they all have agreement on a target to aim for. Figure 25 Using visualization of street sections to consider right-sizing options Source: StreetPlan.net 

88 White Papers for Right-Sizing Transportation Investments Figure 26 Illustrative design concept enabled by alternative intersections Source: StreetPlan.net  Illustrative Right‐Sizing Via Multi‐Way Boulevards (Upsizing)  The previous example discussed right-sizing as downsizing. This example highlights an upsizing. In this case a similar arterial as before has just 100 ft available. However, the corridor is extremely congested, and the consensus is that it needs another traffic lane. However, plans also call for high-frequency bus routes, and transition to walkable design. How can so much be accomplished with just 100 feet of space? There is often more space available than meets the eye. In this case existing buildings are setback an average of 60-feet from the right-of-way due to private parking on their sites. Converting the suburban arterial into an urban multi-way boulevard could double the right-of-way on some blocks ‒ a seemingly prohibitive impact, but the biggest change is converting private parking to public. Many businesses recognize they will lose some stalls, but their neighboring businesses often have excess parking, and because it is public, their own customers should find spots within an easy walk of their site. The new arrangement makes it possible to fit six through lanes, and the major Complete Streets investment boosts land values, making it easier for the market to justify the mixed uses the community was hoping to see.

89 White Papers for Right-Sizing Transportation Investments Figure 27 Illustrative design concept: from typical arterial to multi-way boulevard Source: StreetPlan.net  4.7. Considerations for Right-Sizing Freeways Figure 28 is a satirical rendering of where we could end up if we continue to try to build our way out of freeway congestion. It helps highlight how freeways tend to receive huge investment, while arterials tend to receive relatively little. Some freeways are so popular that there is seemingly endless demand, and communities are seriously debating major double-decker projects, either below or above ground level. Figure 28 Illustration of the risks of trying to build our way out of freeway congestion Source: Collage assembled by Metro Analytics. Left image courtesy of philip.greenspun.com. Others are public  domain. Originally posted at: https://www.strongtowns.org/journal/2017/10/12/how‐to‐tame‐your‐dragon‐ freeway‐edition   On the other end of the spectrum, there are many less critical freeways that are nearing the end of their useful life. Many of those have more volume than can be managed easily on a single at- grade arteria, but not that much more. Situations like this call into question the wisdom of rebuilding dozens of bridges at great expense for a divisive asset that may not be the best solution. This section explores when it makes sense to consider freeway removal. Then, for

90 White Papers for Right-Sizing Transportation Investments freeways more likely upsize than downsize, it explores reasons to avoid upsizing, and offers strategies for matching demand to limited supply. When Freeway Right‐Sizing Means Downsizing  The list of cities that have removed freeways is growing: Portland, Milwaukee, San Francisco, Rochester, and internationally in Seoul, Korea, and Madrid, Spain. Many others have been routed underground or relocated to less populated areas. In all cases, post-removal traffic congestion was not as bad as feared. Many more cities are in various stages of planning for removal or major alteration. The following are some factors that could make it worth exploring freeway removal or serious alteration: CBD Mixed Uses: “Central Business Districts” were once exactly that ‒ almost exclusively about business. Today, those same CBDs may have lost jobs or gained residents. Combine that with better transit access in many cases, and there is much less need to deliver as many autos downtown as before. Restore Urban Fabric: Which came first, the city or the freeway? In suburbs, it was usually the freeway, but in many cases, blocks and blocks of tight-grid development were removed, and the urban fabric on one side or both sides of the freeway is seriously deteriorated. Under-Utilized or Secondary Freeway? Many downtowns are surrounded by loops and extended, elevated ramps. While present volumes on these secondary routes may be higher than an at- grade street can handle, it may also be very likely much of that traffic would divert to alternative routes, times, or modes. If most trips on these facilities are to downtown rather than through, then they are virtually at their destination anyway and may be able to navigate at-grade. One-way Couplets, Boulevards, and the Alternative Grid: Some freeways have been replaced by two-way boulevards but designing low-speed pedestrian-friendly one-way couplets may also be a good option. Couplets can handle higher volumes, and achieve excellent signal progression, which means traffic can travel faster than on a two-way street, even if its speed limit is slower. Network analysis can help reveal the ability of the at-grade system to absorb the change with one-ways, boulevards, and other available streets. Primary Throughway? In cases where volumes are high, and a large portion of that volume is traveling through downtown, going at-grade for a mile or less may be ok if the network can handle it, but it will be politically challenging. If the benefits of removal are high enough, it may be worth exploring how many lanes are truly needed for through traffic, and route those lanes underground, or beyond downtown if a pathway is available. Low-Speed Expressway? It is usually taken as a given that freeways must have 70+ mph design speeds, but grade-separation can be designed for speeds as low as 35 mph. Lower speeds allow for shorter weaving sections and more access points because merge/diverge lengths can be shortened. Such a paradigm shift for a short distance of a mile or so through a downtown would allow for multi-way boulevards where the center express-lanes “duck-under” key cross-streets with modest, context-sensitive bridges that have relaxed vertical and horizontal curvature

91 White Papers for Right-Sizing Transportation Investments requirements, and possibly even lower height clearance requirements. If there is significant through traffic, the choice need not be just between Big Dig tunneling to support 60 mph traffic underground or stop-n-go averaging 10 mph traversing stop-lights on boulevards. An in-between 35-45 mph free flow “by design” can be a good option. Every few years, the Congress for New Urbanism updates its “Freeways without Futures” publication,52 highlighting the top 10 freeways in the country they believe have the weakest arguments for continued existence. I-345 in Dallas is presently on that list, in large part because credible alternatives are being seriously debated. I-345, an elevated freeway, is just over a mile in length, and nearing a decision-point as to whether to rebuild it at great expense or convert it to an at-grade boulevard at much lesser expense. There is an excellent historic grid in the area, and real estate professionals have estimated the removal would generate over $4-billion in real- estate investment over 15-years, with $110-million in property tax revenue to the city.53 I-345 presently carries about 160,000 vehicles per day, of which 75% are passing through downtown.54 If downsized to an at-grade arterial, some of that through traffic will continue to traverse the one mile from the end of one freeway to the beginning of the next, but much of it will divert to alternative routes. TxDOT is still working through its options, but there are strong arguments for major downsize modifications to this freeway. Figure 29 Example, Seoul, South Korea Source: Seoul Metropolitan Government.  52 https://www.cnu.org/highways-boulevards/freeways-without-futures/2017 53 http://anewdallas.com/economics.html 54 http://anewdallas.com/traffic.html In 2001, Seoul elected Lee Myung‐bak as mayor largely on his promise to remove the Cheonggye  freeway and restore the creek, and 80% of residents backed his plan. The project result was so well  received that he was elected president of South Korea, and they have since dismantled 15 expressways.  BEFORE AFTER

92 White Papers for Right-Sizing Transportation Investments Figure 30 Example, I-345 in Dallas Source: Patrick J. Kennedy, Space Between Design Studio.  Finding an End to Endless Upsizing  Equally challenging in the right-sizing debate is when freeways have little room left for additional lanes. They crawl along in stop-n-go conditions and projections show future traffic would easily fill any new capacity (if it were possible to create). In these cases, the typical reactions are to tolerate hours of stop-n-go, addressing it with projects that chip-away at the problem such as parallel transit or improvements to alternative routes, or build our way out once again, this time with a double-decker that will last for 5-10 years. However, there is hope. Delaying expensive decisions by instead adopting politically feasible strategies can buy time for next-generation technologies and new political paradigms to materialize. Some such strategies are discussed below.

93 White Papers for Right-Sizing Transportation Investments Managed Motorways: This is a technique that is proving politically possible today. It was pioneered in Australia and is likely to be implemented soon in the United States. To understand the strength of Managed Motorways, it helps to first appreciate what happens when freeways fail, as it is worse than just slow. Freeways can carry a flow rate of 2,200 vehicles per hour per lane ‒ for about 10-minutes. In other words, they never actually carry their full potential for a full hour (a fact that is overlooked by a great many regional travel demand models). Instead, when there are no gaps for entering traffic, break-lights come on as new traffic attempts to fit. The result is a stop-n-go wave that causes throughput to drop from 2,200 to as low as 800 to 1,500. Traditional ramp meters help organize flow, but do not prevent overload. Managed Motorways is a process of installing sensors, so computers can detect when the mainline is approaching overload, then automatically adjusting ramp meters upstream to create gaps. That ensures the system can “hover” permanently at 95% efficiency, instead of hitting 100% for a short time, only to then collapse to 40-70% efficiency. It is true that to accomplish this, average wait times at on- ramps will increase at 5-pm. That can be concerning to the public, until they realize an extra 5- minutes at the on-ramp can save them 30-minutes of stop-n-go delay. Some DOTs explain it with a visual experiment in public meetings, where they dump rice or pasta into a funnel all at once, vs. pouring it in slowly. If the rice comes in too fast, it plugs up, requiring finger-taps to get it going again. The metered side can finish far more quickly. Congestion Pricing: When demand for freeways exceeds supply, we usually accept as fate that we must build more. But it is possible to match demand to supply through pricing ‒ the same way demand is matched to limited supply at popular restaurants, sports arenas for championship games, and every other location in the economy where there are limits to what is available for consumption. So far, congestion pricing has not proven politically possible in the United States. HOT lanes and tolled facilities are the closest compromise. However, a need for new revenue sources, technology improvements, and wider discussion of public-private partnerships for infrastructure management, should cause congestion pricing to be explored as part of any “Big Dig” conversation. Pricing is often seen as a “double-tax,” but can in fact be shown as a lower overall tax, since it offsets the need to raise taxes for expansion projects. It can also be shown as a net gain to the economy, because the societal benefit and gain to the gross regional product of reliable high-speed mobility far exceeds the user-cost of pricing. Automated Vehicles: It is hard to tell at this point whether automated vehicles will increase or reduce demand on freeways. There are credible scenarios where AVs could reduce demand, and governments will have some ability to influence that outcome. Scenarios that would increase demand reflect continued private ownership, where virtually everyone owns their own private AV. In such a case, long commute times would be less onerous, as the passenger could do productive things while riding. Even if sprawl is exacerbated due to associated induced demand caused by “drive until you qualify” for far-away housing, AVs will be able to shorten the safe following distance between vehicles, thereby boosting freeway capacity well beyond 2,200 vphpl. Thus, congestion on freeways may not increase even if off-freeway regional infrastructure increases substantially. However, AVs may well be employed in significant numbers to provide multi-passenger ride-share services where a single vehicle carries many passengers with similar origins and destinations.

94 White Papers for Right-Sizing Transportation Investments Existing trends with the popularity of ride-share apps like Uber and Lyft, along with rising generations more inclined to use rental services of all kinds, and technologies such as managed motorways all portend that deciding now to continue super-sizing freeways could soon prove to be a great waste of resources that otherwise could have been used for improving other aspects of the transportation system. Curve of Diminishing Returns: At a certain point, the cost per lane mile goes up exponentially, while incremental capacity gained is barely noticeable given inefficient lane utilization, weaving effects, and higher propensities for system-crippling incidents. For most freeways, that point occurs at 5-6 lanes each direction, if not sooner. Whenever models estimate future demand will exceed 6-lanes each direction, regions should explore investments in alternative routes, modes, and matching demand to available supply to begin breaking the cycle of dependency on increased vehicular capacity. Rather than investing a billion dollars to super-size the freeway and create more induced demand, a credible analysis could show the benefit of investing that money in an arterial street network and alternative modes. A Word About Models of Future Traffic: Forecasting is challenging. Some modeling deficiencies or challenges are known, while others may not be recognized. Few models account for either induced demand or “reduced demand” that come from land-use changes associated with high- speed freeways vs. complete street arterial investments. Few consider changing demographics very well, and virtually none make any allowance for pending efficiency gains that could come from managed motorways, congestion pricing, or automated vehicles. There is reason to be skeptical of forecasts that show disastrous freeways in the future unless they are super-sized. Cities are resilient in ways that are not well understood and tend to adjust to their realities. It may well be possible to “just say no” to additional freeway expansion and focus instead on strategies to improve a situation without additional expansion. 4.8. Local Design Concepts for Right-Sizing This section presents specific design concepts that address different types of right-sizing needs, primarily at the level of road networks serving different types of development. Right‐Sizing Local Residential Streets  Over built, single-family residential streets are a major long-term maintenance burden for local governments. Cities often mandate that new development have enough pavement for two vehicles to easily pass each other with vehicles fully parked on both sides of the street. However, on a huge number of streets, there are few, if any, parked cars. And while speed limits on such streets are usually 25 mph, speeds of 35+ are far more likely as wide views lead drivers to exercise less caution.

95 White Papers for Right-Sizing Transportation Investments Figure 31 Wide single-family residential street Source: Metro Analytics  Two-Way Yield Street: In Greenfield development, this can be improved easily with a “yield street” configuration as shown in Figure 32 and recommended in NACTO’s “Urban Streets Design Guide.” When two cars are parked across from each other, only one vehicle will fit through. But since parking will usually be less than fully utilized, it is easy for one vehicle to pull-over while the other moves through. Figure 32 Two-way yield street Source: StreetPlan.net  Half-Parking, One-Way Residential: It is also possible to minimize pavement even more by eliminating parking on one side of the road and making the street one-way to access the remaining parking. For many situations where sufficient off-street parking will be available, this will prove fine. For rare occasions, such as parties where all parking will be utilized, visitors may need to park a street or two away. That may be acceptable given the added expense of infrastructure and consumption of additional land for parking that is under-utilized most of the time.

96 White Papers for Right-Sizing Transportation Investments Figure 33 One-way residential street Source: StreetPlan.net  Right-Designing with Tree Zippers: There are many depressed value, single-family neighborhoods where infill is desired. If these neighborhoods can be reinvigorated, it will deter the need for new infrastructure on the fringes. One excellent way to reinvigorate neighborhoods is to plant uniform street trees with canopies that will eventually shade the road. In cases where there is too much pavement and an insufficient park-strip for trees, a “tree zipper” concept can be created, as in the photo below. The concept is simple: remove the hard, compacted road base from the parking area, and replace it with soil for the root zone and pervious pavers and runoff channeling. This is also a great Greenfield treatment. Benefits include: 1. Shading which reduces heat islands and prolongs pavement life 2. Reduces top speeds and increases property values substantially 3. Spurs reinvestment in adjacent properties, curtailing infrastructure at the fringe 4. Maintains on-street parking, and creates a sense of “right-sized” for residential areas. Figure 34 Tree zipper Source: Metro Analytics 

97 White Papers for Right-Sizing Transportation Investments Right‐Sizing School Zones and Pedestrian Zones  When a street is first built, the adjacent uses that emerge next can render the street “wrong” for the situation. For example, three-lane collectors with under-utilized shoulders are very common street types, and unfortunately it is also very common for public schools to be built adjacent to such streets. In this case, the regular speed limit is 40 mph adjacent to a school but drops to 25 mph just before and after school. Nevertheless, children fatalities can occur just outside of those hours. The situation calls for rethinking the design, since schools attract children and families on foot throughout the day. Figure 35 Example right-sizing in a school zone Source: StreetPlan.net  One option, shown in Figure 35, is to not change anything about the location of sidewalks, curb, and gutter, but install tree zippers with a planted median and pedestrian refuge through the most sensitive space instead. Lanes would be narrowed to 10-feet, and a raised, alternatively colored, table-top crosswalk would all help ensure compliance with a of 25 mph speed limit. The increased travel time is miniscule since only a block or so is affected. Such changes may also encourage parents to allow their children to walk or bike to school.

98 White Papers for Right-Sizing Transportation Investments Right‐Sizing with Place‐Making Alternative Intersection Design  High-efficiency intersection design strategies are just starting to catch on nationally. Continuous flow intersections (CFI), roundabouts, and diverging diamond interchanges (DDI) are among the most popular. Designs like the CFI are inherently auto-oriented. While they may be the right choice for the situation, they lack ability to attract much infill development and may not offset new infrastructure at the fringes. Other designs such as quadrant roadways, thru-turns, and town center one-way couplets are also high efficiency and have considerable place-making potential, but the few built so far aim solely to improve traffic flow, and thus have failed to take advantage of their place-making potential, and thereby their ability to offset fringe infrastructure. Here are some key things to know about innovative intersections. No Left Arrow = More Green Time: Arterial lanes often measure about 700 vehicles per hour per lane (vphpl), while a freeway lane can serve above 2000 vphpl. Why such a huge gap? The single biggest factor is the amount of green time each movement gets at signalized intersections. As two-way arterial streets increase in volume, traffic engineers install left turn arrows to safely cross oncoming traffic. However, left phases reduce efficiency, requiring more time for startup losses, yellow+red, and green time for minor movements. The common thread between all “Innovative” or “Alternative” intersections is managing left turns in a unique way, which in turn reduces the number of signal phases in the primary intersection. The result is higher throughput with less delay. Source: Metro Analytics. Figure 36 Capacity gained with alternative intersections

99 White Papers for Right-Sizing Transportation Investments The Place-Makers: Quadrant intersections, thru- turns, and town center one-way couplets are the high-efficiency designs with the most place- making potential.55 This paper will briefly consider just the quadrant design. First imagine a typical, huge suburban intersection with double-left pockets on all approaches. The quadrant replaces that by routing left-turning traffic behind development using mid-block signals as shown here. The previous double-lefts contributed to an inferior pedestrian environment, but now the median can be for transit stations and queue jumpers or be narrowed and landscaped to include pedestrian refuge. The two-way quadrant road, or “backage road,” doubles as access to parking, making it easier to control access near the main intersection, and eventually redevelop with shared-wall buildings. The increased visibility on the back side activates more parcels for mixed-use development, helping the node intensify to a more formal “activity center” that can support transit. New mid-block signals would seemingly slow traffic, but they can usually be coordinated easily with the main intersection, and the reduction in congestion at the main intersection more than makes up for any increased delay at the mid-block sites. Mid-block signals also make it easier for pedestrians to cross, increasing the livability of the new activity center. While it is best to design such quadrant opportunities in the beginning, there are sites nation-wide near strip-malls and Big Boxes where such pathways are feasible. Converting a “Stroad” to a “Livable Boulevard” with Quadrants  “Stroad” is a term coined by the popular StrongTowns.org to describe arterial streets that are “wrong-sized” for their situation. A stroad is both a “road” ‒ attempting to serve long-distance trips at high speeds, and an economic generating “street” ‒ attempting to serve short-trip localized economic activity, historically accomplished at low speeds in walkable environments. The term is intentionally negative, to point out that what started out as a noteworthy road function ends up as the default location for economic interaction. The situation becomes “wrong- sized,” as the arterial isn’t working well for long-distance, high-speed trips, nor is it working well as a place with ever-increasing economic value and livability. Such stroads are a significant share of what citizens are unhappy with when they express a desire to right-size an arterial street. In high-traffic situations, many engineers aiming to right-size 55 Visit InnovativeIngersections.org for more information. Source: Metro Analytics. Figure 37 Quadrant Roadway Intersection

100 White Papers for Right-Sizing Transportation Investments the situation find they cannot do much because they feel they must manage traffic and are unable to do so without “double-lefts” and other features that detract from livable environments. Figure 38 is a depiction comparing the stroad intersection to the redesigned intersection that relies on the quadrant design. Both have the same through lanes and same right-turn pockets, but the narrower lanes and other features help ensure traffic will obey the reduced speed limit. There is considerably more space available for alternative modes, not only because lanes are narrower, but also because the double-left was reduced to a 12-ft, planted median with pedestrian refuge. Of course, a block or so away will be a single-left lane, which may well be able to handle all lefts that previously needed a double-left, because at a secondary intersection the lefts can get more green time. Despite a reduced speed limit, it can be demonstrated in microsimulation software that the average traverse speed will likely increase (drive slower, travel faster). Showing a before/after simulation goes a long way toward public acceptance, not only because it’s clearly less congested, but also because increased walkability can catalyze mixed-use development. Figure 38 Illustrative right-sizing: innovative intersection v. “stroad” Source: StreetPlan.net  Linkage Between Backage Roads and Quadrants   Recall earlier a best-practice suggestion for right-sizing greenfield arterials is to help ensure they will gain continuous back-ways behind development that fronts the arterial. Figure 39 shows how two crossing arterials would look if each had continuous backage roads. Notice that near the main intersection, the backage roads form quadrant pathways, which can be used to reroute left

101 White Papers for Right-Sizing Transportation Investments turns. The presence of backage roads does not require left rerouting, but they do make it possible to do so at any time. Figure 39 Linkage between Backage Roads and Quadrants Source: Metro Analytics  Quadrant Case Example  While quadrant pathways that could be used for rerouting left turns exist at thousands of locations, it is still very rare to see lefts intentionally routed on those paths and denied at the main intersection as a traffic management strategy. One of the first projects to do this was opened in March 2012 at SR-73 and US-21 in Huntersville, NC. This design routes both WB to SB, and EB to NB left turns on the single quadrant shown here. The design was much cheaper than other solutions, but businesses in the area were very worried it would confuse drivers. Peak hour delay had been over two-minutes at the primary intersection. The quadrant created three signalized intersections. Added together there was still less than one-minute of delay. One comment, typical of many, said, “I was opposed to this intersection when you were planning it, and I still don’t understand why you did it… but I want to let you know that it works!” This design lacks many of the place-making features, but it did simplify the intersection and created additional signalized pedestrian crossing opportunities. The 7‐D’s of Right‐Sizing for Traffic  There are at least seven focus areas of right-sizing for traffic that fortunately can all be described by a ‘d’ word. The traditional approach is the “direct” approach, or “build your way out” approach, which equates to increasing vehicle capacity directly on the facility in question. However, there Figure 40 Single-Quadrant Example Source: Metro Analytics.

102 White Papers for Right-Sizing Transportation Investments are other “d-strategies” to evaluate that can help reduce demand to make room for other things. And even when direct new capacity is a good idea, there are place-making methods for increasing vehicle capacity, as noted earlier, and these should be included for analysis to discern their applicability over more auto-oriented capacity solutions. 1. Design – Connected through streets in the background helps arterials work better. 2. Divert – When aiming for less traffic, look for opportunities to improve competing paths. 3. Deduct – Help people deduct themselves from traffic by improving alternative modes. 4. Delete – Delete vehicle miles traveled (VMT) by optimizing land uses; reducing speeds. 5. Dynamic – Technology dynamically guides to under-utilized streets, and other efficiencies 6. Direct – After pursuing previous strategies, increase capacity directly on the corridor 7. Deal with it – There is psychological benefit to “accepting things you cannot change.” 4.9. Additional Strategies for Right-Sizing Regional Infrastructure Many regions are nearing crisis, with vast amounts of infrastructure nearing 3-5 decades in age, and insufficient revenue to maintain it. Much of the existing infrastructure serves at only at a fraction of its potential, and yet these same regions are building more at the fringes because their interiors are unattractive to new development. In many cases interior streets can be made attractive for new development at a fraction of the cost of new infrastructure at the fringe, but complete streets, street trees, and arterial rejuvenation are viewed as mere amenities, secondary to the more critical tasks of traffic management. Learning from Utah’s 3% Strategy  Whole the above-mentioned improvements are amenities, they are also amenities with the potential to reduce regional infrastructure needs by billions of dollars. Envision Utah’s “3% Strategy” analyzed what would happen if 33% of the region’s future development occurred on just 3% of its most transit-accessible land. Without any additional investments in transit, they found it would reduce regional VMT by about 10%, which would translate into about $7-billion in reduced freeway and arterial street needs, and billions more in reduced local streets and associated infrastructure. This points to the potential benefits of investments that can encourage such land development patterns. Redefining the “Billion‐Dollar Project”  When a region decides to spend a billion dollars, it is often on a single project where virtually everyone understands the value, like a freeway expansion or rail project. By contrast, spending similar funds to enhance arterials with complete streets and local connectivity around would-be activity centers would support development with less exclusive reliance on vehicular travel, thus opening the possibility of saving many billions in offset infrastructure. Nevertheless, funding for such enhancements is usually small because the ability of such “amenities” to offset other infrastructure isn’t well understood, and because any given arterial project is too tiny to garner

103 White Papers for Right-Sizing Transportation Investments region-wide political support. However, if you packaged dozens of arterials together into a single marketable “billion-dollar project,” this might create a situation in which everyone stands to gain something, and therefore funding can be secured. The case for such an investment package would have to show that they projects would make interior arterials flow well and be attractive for reinvestment offsetting new infrastructure at the fringe. Such an approach could be far more effective at helping regions manage their long-term commitments by not building vast amounts of new infrastructure and help respond to and further shape market forces interested in “greyfield” rather than “greenfield” development.

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While not all right-sizing projects involve a change in jurisdictional responsibility and ownership, jurisdictional transfer can be a key tool for implementing right-sizing plans and agreements.

As a supplemental document to NCHRP Research Report 917: Right-Sizing Transportation Investments:A Guidebook for Planning and Programming, the TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 263: White Papers for Right-Sizing Transportation Investments offers practical examples of the current state of the practice. These examples are instructive for developing a roadmap of how agencies can and should approach the role of jurisdictional transfers within competing right-sizing scenarios. In addition, these examples provide assistance to state DOTs and other transportation agencies in implementing the comprehensive approach documented in the Guidebook, as they address critical issues in financing transportation infrastructure.

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