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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
×
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
×
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
×
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
×
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
×
Page 7
Page 8
Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
×
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2011. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors. Washington, DC: The National Academies Press. doi: 10.17226/14579.
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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

S U M M A R Y Research Goals and Objectives The objectives of this research were to (1) evaluate the potential for rehabilitating and reconstructing portions of interstate freeways and similar freeways in the urbanized areas in the United States as new paradigm multimodal transportation facilities and (2) develop strategies to plan and implement these facilities. These facilities might be better used by peo- ple, if the facilities offer passenger mobility by multiple modes and are better integrated into communities. A New Paradigm for Multimodal Corridors Our transportation system and the communities that depend on it are facing serious chal- lenges. People are stuck in traffic—consuming oil, polluting the air, and wasting time. Our transportation infrastructure is aging and inadequate under the weight of increasing travel demand. Our automobile-dominant transportation system becomes inefficient and ineffec- tive during peak hours and emergencies—the times when it is needed most. Public transit is often too slow and limited in coverage to attract automobile users. This report presents a new paradigm for planning, designing, building, and operating multimodal corridors—freeways and high-capacity transit lines running parallel in the same travel corridors (hereafter called “multimodal corridors”). The new paradigm emphasizes building transit lines and supporting pedestrian and bicycle facilities with the following goals: • Enhancing corridor transportation capacity and performance without adding free- way capacity, by building and operating transit lines (including bus rapid transit, light rail, heavy rail and commuter rail) • Building and operating successful transit systems in multimodal corridors that attract high transit ridership and encourage livability and environmental sustainability • Transforming a corridor’s land uses and activities to a more transit-oriented pattern. The old paradigm developed transit lines to compete directly with their freeway neigh- bors for long-haul corridor trips and as a congestion reliever service. New paradigm multi- modal corridors provide market segmentation—distinct, separated, and optimized travel markets for each mode—between the transit line and freeway. Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors 1

2Market-segmentation between transit and freeway is achieved using the following guid- ing principles and techniques: • Market-Segmented Transit and Freeway Designs (Multimodal Coordination): Sta- tion spacings and interchange spacings along each facility are designed to give each mode an advantage either in long-haul or short-haul corridor trips. The new paradigm multimodal corridor offers the opportunity for each mode to thrive and potentially increases the total carrying capacity of the corridor. • Market-Segmented Urban Form Patterns: The new paradigm multimodal corridor encour- ages the development of separated, distinct land use and urban design environments for each mode within the same corridor. Transit station areas should have high-density, mixed- use, pedestrian-oriented land uses and urban design characteristics. Freeway interchange locations should have lower density, separated uses with street designs conducive to smooth traffic operations and freeway access. • Market-Specific Station Access: Automobile-oriented (called here, park-and-ride access) multimodal corridors focus on providing freeway-competitive transit speeds and prioritize auto and bus access to their stations. Transit-oriented multimodal corridors focus on maximizing transit line access to corridor land uses via nonautomobile modes while dis- couraging automobile access. • Market Segmentation through Constrained Freeway Capacity: Although often politi- cally unpalatable, some multimodal corridors have developed divided travel markets by constraining the capacity of the freeway. Putting a low ceiling on the carrying capacity of the freeway gives the transit line an operational advantage, particularly for long-haul cor- ridor trips. • Coordinated and Distinct Intermodal Operations: The new paradigm incorporates two approaches to maximize interoperability among the transit line, the freeway facility, feeder bus lines, and pedestrian and bicycle facilities. • Intermodal Connections Limited to Key Locations: The new paradigm corridor encour- ages intermodal transfer stations—where park-and-ride lots, bus transfer facilities, nearby freeway interchange ramps, and cross-corridor pedestrian and bicycle route facilities encourage intermodal transfers—to be built at end-of-the-line (terminal) locations and key midline locations. • Intermodal Intelligent Transportation Systems: Intermodal transfers between freeway and transit can be facilitated and encouraged by real-time traveler information systems that provide information on corridor traffic conditions (congestion and incidents), transit schedule and schedule adherence, comparative corridor travel times (freeway versus tran- sit), and station and destination parking availability and costs. The Old and New Paradigms Compared The key difference between the old and the new paradigms involves the role of the free- way in corridor travel. The interstate was originally designed to serve the type of trips that its name implies: long-haul, interstate trips. However, as the interstate model evolved, interstate freeways became the infrastructure of choice for intraurban travel as well, often displacing transit services into playing a supplementary, congestion-reliever role to their freeway counterparts. The new paradigm seeks to restore freeways to their originally intended role as long- distance, intercity, and interstate facilities and so provide opportunities for transit to again be the preferred intraurban mode. There are important differences between the old and new paradigms. Both in terms of their inherent goals and tangible benefits, the new paradigm offers improved performance

and efficiencies when compared with the old paradigm. Key distinctions include the multi- modal goals inherent in each paradigm, their environmental effects, and the technologi- cal, institutional, and planning techniques and models they employ. These differences are summarized in Table S-1. The New Paradigm Typology and Corridor Evolution The new paradigm offers several paths to develop multimodal corridors. First, a transit- oriented corridor can be built where the transit line is given the design, operating charac- teristics, and surrounding land use patterns that will effectively carve out a near-exclusive corridor travel market. 3 Goals and Benefits Characteristics Old Paradigm New Paradigm Multimodal Goals Corridor Modal Focus Automobile Dominated Multimodal Coordination Supplementary Complementary Freeway Travel Markets Served Short- and Long-Haul Trips Long-Haul/Interurban Trips Transit Travel Markets Served Either Short- or Long-Haul Trips Short-Haul/Intraurban Trips Design Focus Vehicle Throughput Person Throughput Congestion Congestion Relief Reduced Automobile Use Travel Benefits Enhanced Mobility Enhanced Accessibility Freight Increased Capacity Long-Haul/Interurban Focus Environment Environmental Benefits Reduced Congestion-Caused Emissions Reduced Emissions through Mode Shift to Transit Land Use Automobile-Oriented Transit-Oriented Near Stations through Coordinated Corridor Land Use Controls and Policies Station Access Automobile Access Pedestrian/Transit Access Institutions and Planning Institutional Coordination Highway Department Lead Multimodal Agency Partnerships Planning Focus Responds to Forecasted Travel Demands Shapes Future Pop. & Travel Growth Planning Approach Ad Hoc Design of Transit in Corridor “Intentional” Multimodal Design Implementation Transit Right-of-Way (ROW) “Leftover” ROW in Freeway Corridor • Possible Freeway Lane Conversion for Transit • “Intentional” Multimodal Design New Technologies Goal Freeway Capacity Maximization • Modal Coordination • Maximize Person Capacity Tools • Vehicle Detection • Ramp Metering • Traffic Management Center • Electronic Fare Payment • Multimodal Traveler Information • Parking Applications • Freeway Demand Management • Incident Management • Congestion Pricing • Coordinated Multimodal Pricing • Coordinated Multimodal Incident Management • Corridor-Level Parking Management Table S-1. Comparison of the benefits and goals of the old and new paradigms.

4The second path involves a two-step process of multimodal corridor planning, design, and construction. In the first step, transit facilities are designed and built in freeway corri- dors with performance characteristics that enable them to compete with the freeway facility on a travel time basis. Then as the corridor evolves, infill stations can be built that provide greater coverage and accessibility for the transit riders to corridor land uses and activities, which can further encourage the corridor to develop additional transit-oriented design (TOD). It is conceivable that, over time, this process can lead to the conversion from a purely automobile-oriented, freeway-dominated corridor to a park-and-ride-access multi- modal corridor to a transit-oriented corridor. As discussed in the research report, a new paradigm multimodal corridor would take one of three forms: • Transit-oriented multimodal corridors are designed to give transit a performance advan- tage in serving short- and medium-length trips, while the freeway is given a performance advantage for serving long-haul corridor trips. • Park-and-ride access multimodal corridors are designed to provide high levels of auto- mobile access within, and high transit speeds through, the corridor. • Transit-optimized/freeway-constrained multimodal corridors are designed to give transit a performance advantage in the corridor by constraining the capacity and perfor- mance of the freeway. Corridor Evolution The travel patterns and built environments of corridors can change dramatically over time. Although the new paradigm offers three different types of multimodal corridor (as described above), each of these is not seen as a necessary end state. The new paradigm encourages the evolution from freeway-only, automobile-oriented, and old paradigm corridors into transit- oriented corridors. Park-and-ride-access and transit-optimized/freeway-constrained corridors are not end states, but steps along the path to livable, sustainable, efficient transit-oriented corridors. Figure S-1 illustrates this progression. The Key Factors for Successful New Paradigm Corridors The degree to which transit competes directly or works cooperatively with its freeway neighbor is the critical determinant of transit success in a multimodal corridor. Multimodal corridor transit and freeway systems often are built to compete directly with each other for the same travel markets. When this happens, one mode can dominate, and the freeway typically attracts the most patrons. As a result, the surrounding land uses and activities will be shaped to serve the freeway, leaving transit underpatronized. The new paradigm for multimodal corridors offers insights into the competition between freeways and transit and how this competition can be structured, effectively carving out travel market niches where each mode can thrive. Multimodal Corridor Design and Operational Tradeoffs The critical choices made for a multimodal corridor’s design revolve around the advantages and disadvantages given to each mode, both as stand-alone facilities and in relation to one another. Sometimes, an advantage given to transit comes at the expense of the performance of the freeway and vice versa. Several tradeoffs between performance and design charac- teristics have been identified in this research to frame the discussion of the new paradigm. Each of the tradeoffs represents the aggregation of many individual corridor choices and

5Freeway Capacity Constraint LEGEND Transit Line Transit Sta. Freeway Freeway Int. Upstream (Non-CBD) Segment Downstream (CBD) Segment - Freeway dominates corridor travel - Automobile-oriented land uses Freeway-Only Corridor - Freeway dominates corridor travel - Transit as congestion reliever - Automobile-oriented land uses - Long int. & sta. spacings - Sta. & int. co-located - Park-&-ride access emphasis for sta. Old Paradigm Multimodal Corridor - Transit focused on long-haul corridor trips - Freeway focused on short-haul trips - Automobile-oriented land uses - Short int. & long sta. spacings - Sta. & int. co-located - Park-&-ride access emphasis for sta. New Paradigm Corridor: Park-&-Ride Access - Hybrid multimodal corridor - Park-&-Ride segment: upstream - Transit-Oriented segment: downstream New Paradigm Corridor: Transit-Optimized/ Freeway Constrained - Transit focus on local access & short-haul trips - Transit-oriented land uses - Long int. & short sta. spacings - Sta. & int. separated except for intermodal sta. - Non-automobile access emphasis for sta. New Paradigm Corridor: Transit-Oriented Figure S-1. Possible paths to developing transit-oriented new paradigm corridors.

6characteristics. The successful development of a new paradigm multimodal corridor depends on selecting and combining them and in doing so to achieving the desired tradeoff and per- formance ends. The following is a list of critical tradeoffs that describe and determine the relative success of a multimodal corridor: • Transit corridor accessibility versus operating speed • Freeway accessibility versus operating speed • Freeway capacity versus transit ridership • Transit-oriented versus automobile-oriented urban form • Local access versus intermodal transfer oriented stations • In-median and adjacent versus offset freeway alignment • Supplementary versus complementary transit and freeway service • Fixed versus flexible transit routing • Incremental versus concurrent corridor planning approaches Evidence on the Patronage Impacts of Multimodal Corridors When transit and freeways compete with each other, the old paradigm resigned transit to take second place, serving as the overflow service to the freeway during peak congestion periods and suffering from low ridership. But analysis of existing multimodal corridors suggests transit does not need to play this role. There are transit lines that thrive in the same corridors as freeways. This study found the following characteristics correlated with multi- modal corridor success: • Multimodal corridor coordination: Total corridor patronage (transit and freeway) tends to be higher in corridors with complementary coordination. Complementary coordination describes the conditions where the transit and freeway facilities are designed and operated to serve different travel markets, primarily by providing either wide station spacings paired with short interchange spacings (automobile-oriented) or short station spacings and long interchange spacings (transit-oriented complementarity). • Transit-oriented corridor urban form: Transit patronage is higher in corridors with transit-oriented land uses and urban design characteristics. Corridor urban form is divided into four components: density, diversity, design, and clustered destinations. • Transit-oriented station access: Transit ridership is lower in corridors where freeway ramps touch down near transit stations. Corridor station access reflects the design and operational elements within and near stations that encourage either auto access (automobile-oriented) or pedestrian and other nonautomobile access (transit-oriented) modes. A high number of freeway ramps that touch down near transit stations coupled with park-and-ride lots that surround transit stations impede pedestrian station access. Based on a combination of quantitative and qualitative analysis of the multimodal corridor case studies, the research team identified the following desirable attributes for multimodal corridors: Transit-oriented corridors: • High-capacity/fixed-capital-asset transit modes such as heavy rail, light rail and BRT • Transit-dependent-rich market • Concentrated station-area land uses

• Distributed nodes maximize activities served along entire route • Clustered mixed-use destination(s) at many locations along corridor • Balanced jobs and housing in corridor (jobs clustered in station areas but dispersed along corridor) • Limited parking supply and high cost of available parking within destination CBD • Radial metropolitan alignment with transit line serving more than one activity center along route • Transit-oriented land uses and urban design around stations • Stations located either adjacent or offset from freeway • Short station spacings • Long interchange spacings • Ramp touchdowns located far from stations • Station access: – Intermodal stations only at terminal corridor locations and major freeway-to-freeway interchanges – Community-oriented station access modes – “Green connector” paths leading to stations Park-and-ride access corridors: • At least one large activity center or anchor, usually a CBD with high levels of employment • Direct access to the city center and other major “anchors” (This likely involves leaving the freeway to penetrate these areas) • Limited and costly parking in the CBD • Effective transit distribution in the CBD, preferably off-street • Constrained freeway capacity such as lane drops, route convergence, and travel barriers • Wide station spacing that permits high transit speeds • Good access to stations on foot, by car, and/or by public transport; a limited number of free- way interchange ramps within walking distance of transit stations • A multimodal corridor that extends at least 10 miles and has at least eight residential “catch- ment” stations • Transit-supportive development in the environs of key stations • An interagency multimodal corridor overlay zone that can specify uses and densities and form guidelines and requirements Transit-optimized/freeway constrained corridors: • Freeway bottleneck (lane drop or other capacity constraint) roughly mid-point in the corridor that gives transit a travel time advantage in CBD side of corridor. • Transit-oriented corridor qualities downstream of freeway bottleneck • Park-and-ride access corridor qualities upstream of freeway bottleneck The Institutional Landscape for Multimodal Corridors Getting a multimodal corridor built is one thing, but building a successful, balanced, and coordinated new paradigm corridor requires a unique combination of collaboration, flexibility, and single-minded tenacity on the part of the project’s stakeholders. Multi- modal transportation systems require cooperation and collaboration between different levels of government (for example, federal, state, regional, and local), different agencies with mode-specific missions (for example, state freeway departments, transit agencies, and 7

8city streets and roads departments), and different public agencies with divergent missions (for example, city land use planning departments and transit agencies). During the past 50 years these organizations have evolved from being somewhat limited, mode-specific organizations into more multimodal agencies. As such, they are now better poised to plan, design and implement new paradigm multimodal corridors. In particular, the Intermodal Surface Transportation Efficiency Act (ISTEA) legislation brought key innova- tions into practice, including policies specifically directed at breaking down the barriers between institutions that have prevented multimodal projects from being developed. New Paradigm Barriers and Opportunities The complexities of multimodal corridor projects result from a combination of institu- tional, political, technical, and planning barriers. While some issues arise routinely in transit and highway projects, multimodal corridor projects must address the larger union of these two sets of issues. Types of Barriers This research has explored how various spatial, institutional, and financial barriers can inhibit successful new paradigm multimodal corridor development, and the development of a mix of activities and land uses along a corridor that can justify and support these infra- structure investments. Physical or spatial constraints pose tangible limitations to the successful placement and operations of multimodal corridors. These include • Regional urban structure • Right-of-way and footprint constraints Institutional barriers hinder the development of multimodal facilities that may other- wise meet spatial and financial requirements for success. Institutional barriers include the formal goals and objectives pursued by stakeholders, the effects of widely held perceptions and biases, and the institutionalized habits and inertia that affect established organizations, partnerships, and relationships with the public. These include • NIMBYism (“Not in my Backyard”) • Mode bias • Political barriers • Policy barriers • Land use/zoning barriers • Administrative barriers Overcoming Barriers Despite the barriers to planning, building, and operating successful new paradigm multi- modal corridors, there are many tools and approaches to overcome barriers. These include practical approaches and strategic measures such as • Viewing every corridor for its multimodal potential • Building constituencies around multimodal alternatives • Identifying potential linkages, sharing, and trades

• Building the organization(s) around the project • Reducing administrative barriers • Focusing on quality design and service • Prioritizing access area (around stations and interchanges) land uses • Developing access points as coordinated and mode-segmented travel markets Table S-2 provides an overview of the differences in planning, design, and operational approaches between the old and new paradigms. 9 Characteristics Old Paradigm New Paradigm Motivations for Planning Reacting to economic growth and community and environmental impacts Proactive planning for economic, community, and environmental goals Setting Priorities Moving vehicles Moving people and freight Assessing Needs ♦ Capacity ♦ Throughput ♦ Travel time costs ♦ Reliability ♦ Reduced delay times ♦ Accessibility ♦ Business logistics ♦ Economic competitiveness Analysis Approaches Individual modes and facilities End-to-end trips focusing on multiple modes and the connections between them Planning Processes Emphasis on individual jurisdictions Balanced approach to meeting local, regional, state, and national transportation needs Table S-2. Approaches to planning, design, and operations for old and new paradigm corridors.

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TRB’s Transit Cooperative Research Program (TCRP) Report 145: Reinventing the Urban Interstate: A New Paradigm for Multimodal Corridors presents strategies for planning, designing, building, and operating multimodal corridors—freeways and high-capacity transit lines running parallel in the same travel corridors.

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