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Developing an Expanded Functional Classification System for More Flexibility in Geometric Design (2018)

Chapter: Chapter 4. Alternative Classification Systems

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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
×
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
×
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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Suggested Citation:"Chapter 4. Alternative Classification Systems." National Academies of Sciences, Engineering, and Medicine. 2018. Developing an Expanded Functional Classification System for More Flexibility in Geometric Design. Washington, DC: The National Academies Press. doi: 10.17226/25178.
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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.

37 ALTERNATIVE CLASSIFICATION SYSTEMS EXISTING ALTERNATIVE CLASSIFICATION SYSTEMS The project team identified 17 recently developed systems that rethink or have developed alternatives to the current FCS. After reviewing all 17, ten were selected for detailed investigation because they had improved context definition, accommodated modes in a holistic manner, or had design guidance based on context and roadway type. These systems represent the breadth of thinking on the subject, and have good geographic and jurisdictional distribution. This section identifies alternative classification systems that agencies have implemented to address the shortcomings of the FCS. The various factors considered in each classification system are identified to determine how they define context. Other elements — beyond the access and mobility criteria currently used — are identified as well. Criteria were developed to evaluate the nine alternative classification systems. They focused on the following questions: • How is context defined? o This addresses the range of contexts considered and the required data used to define them. • How are modes accommodated? o This considers the efforts undertaken to address all users including vehicles, pedestrians, bicycles, transit, and any special users (e.g. trucks). • How does the classification system impact geometric design? o This evaluates the impact of the system on the design choices and identifies the elements required to address potential modal priorities. • What is the road function? o This identifies the roadway categories and their associated definitions as it relates to the overall roadway function within the transportation network. Further, the strengths and weaknesses of each system are described. This discussion highlights which components could be incorporated into the proposed alternative system. The following systems are discussed in alphabetical order: 1. Arterial Streets Towards Sustainability (ARTISTS), European Union;

38 2. AustROADS Design Guide, Australia and New Zealand; 3. City of Charlotte, Urban Street Design Guidelines, North Carolina; 4. City of Chicago, Complete Streets Chicago, Illinois Department of Transportation; 5. ITE-CNU Designing Walkable Urban Thoroughfares, Institute of Transportation Engineers and Congress for New Urbanism; 6. Massachusetts, Project Development and Design Guide, Highway Division of the Massachusetts Department of Transportation (MassHighway); 7. Minnesota, Guide under Development, Minnesota DOT; 8. NACTO Urban Street Design Guide, NACTO; 9. Oregon, Highway Design Manual, Oregon DOT; and 10. Pennsylvania and New Jersey, Smart Transportation Guidebook, Pennsylvania and New Jersey DOTs. The seven systems that were considered but not fully discussed here include: 1. Abu Dhabi, Urban Street Design Manual, Abu Dhabi, United Arab Emirates; 2. California, Main Street California: A Guide for Improving Community and Transportation Vitality, California DOT (Caltrans); 3. Connecticut, Highway Design Manual, Connecticut DOT; 4. Los Angeles, LA Model Design Manual for Living Streets, LA County Department of Public Health; 5. United Kingdom, UK Manual for Streets, UK Department of Transport; 6. Vermont, Vermont State Design Standards, Vermont Agency of Transportation; and 7. Washington, Guide under development, Washington DOT. ARTISTS The Arterial Streets Towards Sustainability (ARTISTS) research initiative was sponsored by the European Union in 2004. It proposed a classification system that was sensitive to all users, not just vehicles. Underpinning it is a critical perspective that differs somewhat from what is used in the United States. ARTISTS began with the premise that urban street planning, design, and management lacks an adequate set of standards or parameters for arterial streets, even though these are critical components of urban transportation systems. A primary criticism of the United States’ FCS is that it is based on neither urban nor rural principles and thus ignores environmental context, with arterials in

39 the dominant position in a roadway hierarchy. More information can be found at http://www.transport- research.info/web/projects/project_details.cfm?id=14838. What principally motivated the ARTISTS project was the growing recognition among national and local authorities that classifications do not always reflect actual street uses. Before this, the classification of streets in Europe arose from a similar need to define an overall system taxonomy, comparable to what the United States expressed in its 1968 and 1973 Federal-Aid highway legislation. These classification systems used identified streets to rebuild so they would primarily serve an automobile-oriented function, even if these streets were in a community context that generated a broader range of travel modes and roadway users. The ARTISTS project sought to acknowledge the role of streets as public spaces, especially as many of the streets that it studied had originally been constructed with civic purposes in mind and before widespread automobile use (Marshall et al., 2004). Context Definition The ARTISTS approach looks specifically at “arterial streets,” which are defined as “major streets that are multi-functional — combining a strategic network role with space for other activities, such as crossing movements, shopping, socializing, and other urban activities.” (Marshall et al., 2004) Examining these streets more closely, the ARTISTS approach scrutinizes arterial streets along two axes of context: • Link status — the relative significance of a street section as a link in the network. The link status describes the significance of a street section as a component of the roadway network, with national and regional routes carrying greater weight in this system than city-specific or local routes. • Place status — the relative significance of a street section as an urban place in the whole urban area. If a street segment has a higher link status, more emphasis/street space may be allocated to through traffic, whereas a street segment with a higher place status may confer more emphasis/street space to pedestrians and other street activities (Figure 13). ARTISTS uses two dimensions to describe a street rather than the one-dimensional lines they are often simplified into. This reinforces the possibility of the street as a “place” and works against the continued representation of the street as linear. Combined with the “place” status, this introduces a community context dimension absent from the FCS model, and recognizes that arterial streets are important community elements beyond transportation. This allows a model that gives the roadway

40 system (links) and context (places) equal weight in determining network importance and design criteria for streets. Figure 13 Link and place axes of arterial streets Road Function The ARTISTS initiative was a research effort that provided a general outline for a more holistic and inclusive roadway classification system but in and of itself did not establish or codify one that has become official guidance. Critically, the ARTISTS classification model was presented as an extension of existing engineering-based classification systems, not as a total replacement. This is important in that it retains the technical expertise of transportation planners and engineers, but creates a framework by which these professionals share decision-making responsibility with urban planners. Figure 14 shows a classification table that a city could use to apply the ARTISTS Figure 14 ARTISTS street classification table

41 approach to its city context. Types of streets are laid out according to their relative association with the “link” and “place” axes of the ARTISTS approach. Modal Considerations One of the most notable principles in the manual is its recommendation of a user-based hierarchy instead of conventionally classifying roads strictly based on their transportation function. This situates the pedestrian as the priority user on many residential streets, but also includes cyclists and vehicle parking as well as moving vehicles. The outcome of this approach is a separate set of design concerns for streets serving residential land uses, suspending the more conventional design factors for travel speeds and vehicle-carrying capacity on these streets in favor of factors that promote safety, control speeds, and accommodate the expected range of users. However, a specific modal hierarchy outside of this user-based focus is assigned at the discretion of the stakeholder applying the ARTISTS approach. Design Elements The ARTISTS framework does not provide specific design recommendations but instead outlines the decision-making process that its system is congruent with. This begins with an understanding that street design must consider both physical fit (i.e., is there actual space to accommodate different uses) and compatible use (i.e., the suitability for different uses to be located near each other). Considering the status of “link” and “place” for the street segment, the available street space, existing constraints, and existing users and interests adjudicate decisions between uses that conflict in the same street space. The ARTISTS approach emphasizes stakeholder outreach and sustainability to guide the design decision-making process, which aligns with the overall user- centered approach to ARTISTS. A flowchart of the design decision-making process is shown in Figure 15.

42 Figure 15 Overview of ARTISTS approach fit into a complete decision and design process Strengths and Weaknesses The ARTISTS approach main strength is flexibility. By keeping the underlying foundation of its viewpoint simple, mainly the dual attributes of “link” and “place,” the ARTISTS approach facilitates its application to a wide variety of existing street classification systems, allowing agencies and users to examine their streets through a new lens without completely overhauling their existing methodology. This flexibility means that the ARTISTS approach is very high level without outlining specific classifications or advancing particular design recommendations. Decisions about these are instead left to the decision maker who must use the ARTISTS approach as a loose guide that is used to inform design decisions. In addition, by focusing attention on the individual, the ARTISTS approach takes the consideration away from individual modes and shifts it to the people within those modes. Thus, forcing street designers to remember who they are planning for makes their task more human- centered and grounds the decision-making process in questions of usability rather than just efficiency. While the ARTISTS system provides a well thought out approach to classification, the system relies on an underlying classification and is narrowly focused on urban areas and arterial

43 streets. Expansion of the concept to other contexts and roadway types may present an overly complex systems as ARTISTS identifies 25 unique place and link statuses for a singular roadway type and context. Furthermore, there is a lack of direct connection to design recommendations under the scope of this research. This system can be used to provide guidance and design element selection when overlaid to other alternative systems, but falls short in addressing the full context and user demands necessitated by the research objective. AustRoads Design Guide The road transportation and traffic agencies of Australia and New Zealand collaborate under the AustRoads association. Together they have developed a guidance document on road design. The organization has taken a similar approach to roadway classification as certain context sensitive design examples in the United States, referring to these as the Design Domain concept. Design Domain uses principles closely related to the Practical Design concepts in the United States, with “emphasis on developing appropriate and cost-effective designs rather than providing a design that simply meets 'standards'.” More information can be found at http://www.austroads.com.au /road-construction/road-design/resources/guide-to-road-design. Context Definition AustRoads’ Design Domains are based on the context established by the surrounding land use. A range of land uses, varying from extremely rural to the urban core, is used to understand the context in which the road segment is placed. Adapted from the U.S. Smart Code, Figure 16 shows six main context categories that can be used to describe the road context from very rural to the urban core (www.smartcodecentral.org).

44 Most rural & natural Rural, rural reserve Suburban General Urban Urban Center Urban Core Figure 16 Context categories for AustRoads road classification Road Function The guide recognizes many of the same factors in the FCS that more innovative American guidance documents have also articulated. The AustRoads Guide states “the functional classification of urban roads is usually less clear than that of rural roads, as urban roads generally are flanked by dense development that requires frequent access at the boundary of the road. Historical requirements for curbside parking and other uses (e.g. public transport routes or bicycle routes) further complicate functional definitions.” The FCS designation strikes at the guide’s core, although it emphasizes that all urban streets have a complex transportation function that requires thoughtful consideration, which entails going beyond a reliance on typical standards. By following the Design Domain concept, designers are, as previously noted, encouraged to create appropriate designs, and functional classification is relegated to a later discussion outside of the Design Domain text. Indeed, the principal references that the Guide makes to urban functional classification draw from references in U.S. documents and they adopt the FHWA model as a means of organizing individual roads within the overall system (Table 4 and 5).

45 Table 4 AustRoads functional classification of rural roads Road Classification Description Arterial Roads Class 1 Those roads, which form the principal avenues for communications between major regions, including direct connections between capital cities. Class 2 Those roads, not being Class 1, whose main function is to form the principal avenue of communication for movements between: • A capital city and adjoining states and their capital cities; or • A capital city and key towns; or • Key towns Class 3 Those roads, not being Class 1 or 2, whose main function is to form an avenue of communication for movements: • Between important centers and the Class 1 and Class 2 roads and/or key towns; or • Between important centers; or • Of an arterial nature within a town in a rural area. Local Roads Class 4 Those roads, not being Class 1, 2, or 3, whose main function is to provide access to abutting property (including property within a town in a rural area). Class 5 Those roads, which provide almost exclusively for one activity or function, which cannot be assigned to Classes 1 to 4. Table 5 AustRoads functional classification of urban roads Type of Road Function Controlled access highways (motorways or freeways) Motorways and freeways have an exclusive function to carry traffic within cities and to ensure the continuity of the national or regional primary road system. As they are designed to accommodate through traffic, they do not offer pedestrian or frontage access. Urban arterial roads Urban arterial roads have a predominant function to carry traffic but also serve other functions. They form the primary road network and link main districts of the urban area. Arterial roads that perform a secondary function are sometimes referred to as sub- arterial roads. Urban collector/distributor roads These are local streets that have a greater role than others in connecting contained urban areas (e.g., residential areas, activity areas) to the arterial road system. Generally, consideration of environment and local life predominate and improved amenity is encouraged over the use of vehicles on these roads. Urban local roads These are roads intended exclusively for access with no through traffic function. Modal Considerations The Guide identifies three categories of road users: • Users of motorized vehicles such as trucks, buses, cars, and motorcycles; • Users of non-motorized or low-powered vehicles such as bicycles and powered wheelchairs; and • Pedestrians.

46 The last two groups are classified as vulnerable and, at times, need independent facilities, but the Guide does not include a modal hierarchy. Design Elements The AustRoads Guide de-emphasizes the use of a classification system in roadway design. Instead, it describes the following considerations for designing a thoroughfare: 1. Strategic fit with relevant government policies, strategies and plans; 2. The nature and magnitude of transportation demand on a particular roadway; 3. Road safety; 4. Community views and expectations; 5. Travel times and costs; 6. Freight costs; 7. Public transport provision; and 8. Provisions for cyclists and pedestrians. Each of these eight categories is then discussed in greater detail throughout the Design Guide, with specific guidance on how they should influence particular design controls. However, these are organized at a general level under the Design Domain concept. Designers are asked to consider all design elements and find the best fit for the roadway’s functional demands — and not simply follow standards or view design projects as merely the sum total of their parts. The Guide offers a process summarized in the following illustration and notes. In addition to normal design domain, the AustRoads Guide introduces the Extended Design Domain (EDD). EDD is a range of design values below the minimum values traditionally specified for new roads in road design guidelines. Where used, EDD refers only to this extended range of values. The EDD concept uses values smaller than the practical lower limit in certain circumstances, provided they could be justified and defended based on engineering grounds and operating experience (Table 6). Use of the EDD’s values should be supported by a documented risk assessment that • Justifies and recommends the values to be adopted for various design parameters. • Demonstrates that adoption of lower values is in the overall community interest with respect to investment strategies, road safety strategies, and other strategies that relate to roads and road networks.

47 • Verifies that responsibility for the use of values within the EDD is taken corporately by the relevant road authority and is not placed on an individual designer. Table 6 Normal and EDD The Design Domain is composed of a Normal Design Domain and an EDD, as illustrated in Figure 17. The lower regions of the Design Domain include values that are generally viewed as less safe or less efficient, but usually less expensive than those in the upper regions of the domain. Designers are encouraged to base their decisions on which values to adopt by using objective data on the changes in cost, safety, and levels of service prompted by changes in the design, together with cost–benefit analyses. Such data are not always available, particularly data that relate changes in the values associated with specific design elements and parameters to safety performance. Designers should therefore refer to relevant documents, including the AustRoad Design Guide and research reports, to assess the potential effects of changing values for the various design elements involved. An example of this concept is shown in Figure 18. The value limits for a particular criterion define the absolute range of values that it may be assigned. The design domain for a particular criterion encompasses the range of values, within these limits, that may practically be assigned to it.

48 Figure 17 Design Domain concept, AustRoads Road Design Guide (2006) Figure 18 Design Domain example for shoulder width, AustRoads Road Design Guide (2006) Strengths and Weaknesses The strongest statement in the Guide is “The Design Domain approach places emphasis on developing appropriate and cost-effective designs rather than providing a design that simply meets 'standards'.”

49 A major weakness is the heavy influence of U.S. standards reflected in the functional classification. City of Charlotte In 2007, Charlotte, North Carolina adopted a local set of design guidelines, the Urban Street Design Guidelines, which reflected the imprint of the Smart Growth and Context Sensitive Design movements from the 1990s and 2000s. These guidelines emerged in part as a means to implement the general goals and objectives of Charlotte’s Centers, Corridors, and Wedges regional growth policy as well as its Transportation Action Plan. These long-term plans envision transforming Charlotte into a thoroughly multimodal community. With respect to infrastructure investment, the plans clearly distinguish between areas of redevelopment and areas of neighborhood preservation. Both of these policy documents have extended beyond the realm of serving vehicle traffic. The Centers, Corridors, and Wedges strategy identifies major corridors as the basis for redevelopment. More information can be found at charmeck.org/city/charlotte /planning/AreaPlanning/CentersCorridorsWedges/Pages/Home.aspx. With this larger framework of community transition in mind, Charlotte developed their Urban Street Design Guidelines as a tool for more explicitly recognizing community context in street design and to integrate more flexibility into the design process. The guidelines are also intended to more clearly account for non-motorized transportation options, especially given that the city recognized the necessity of facilitating transit use — even on its existing local bus network — once it began a long-term program of developing premium transit capital projects. More information can be found at charmeck.org/city/charlotte/Transportation/PlansProjects/Pages /Urban%20Street%20Design%20Guidelines.aspx. The city’s guidelines generally follow a context sensitive design process and instruct designers to identify local context as a first step. After this is done, a street is classified into one of five major types. They use a different nomenclature than the conventional FHWA classification, and streets are classified independently of the guidelines. Context Definition In the Charlotte Guide, land use context is the first component of the six-step process that defines the street type classification and selects the best cross section of roadways (Figure 19). The step- wise guidance for a context-based street network defines street types by: 1. Defining the existing and future land use and urban design context;

50 2. Defining the existing and future transportation context; 3. Identifying deficiencies; 4. Describing future objectives; 5. Recommending street classification and testing initial cross-section; and 6. Describing trade-offs and selecting cross-section. Figure 19 Six-step process Within a larger regional framework, Charlotte defined their long-term growth strategies under a framework for activity centers, growth corridors, and wedges - beginning in the 1990s. Figure 20 depicts the 2010 contexts. Under this framework the guidelines further elaborate upon these land use contexts, which are defined in the following manner: • Transit Station Areas; • Centers;

51 • Corridors; • Non-residential uses (Areas of only commercial and office uses); • Residential areas with more than five dwelling units per acre; and • Residential areas with fewer than five dwelling units per acre. Figure 20 Activity centers, corridors, and wedges growth framework The connection between land use context and street type is described in Table 7.

52 Table 7 Connection between land use context and street type Land Use Context Street Types Link between Land Use Context and Street Type Activity Centers • Main Streets • Avenues • Local Streets • Main Streets serve as pedestrian oriented activity centers, walking receives the highest priority of all the transport modes although they also serve transit, bicyclists, and automobiles. • Avenues are found in a wide variety of land use contexts. • Local Office/Commercial Streets will apply to developments ranging from very pedestrian-oriented retail locations (similar to Main Streets) to business parks. The goal is to create a convenient and safe network of well-designed streets. Transit Station Areas • Local Streets • Local Office/Commercial Streets will apply to developments ranging from very pedestrian-oriented retail locations (similar to Main Streets) to business parks. The goal is to create a convenient and safe network of well-designed streets. Growth Corridors • Avenues • Boulevards • Parkways • Avenues are found in a wide variety of land use contexts. • Boulevards are found in a variety of land uses and development intensities context but are not suited for land uses that would foster high volumes of pedestrians crossing from one side of the street to the other. • Parkway design is better matched to land uses that depend on vehicle accessibility; types of uses may include regional or community malls, industrial or office parks, and some types of office/mixed-use/multi-use centers. Once a high level of pedestrian activity is developed roadways should be oriented away from the Parkway design. Non-Residential Use • Avenues • Boulevards • Parkways • Local Streets • Avenues are found in a wide variety of land use contexts. • Boulevards are found in a variety of land uses and development intensities but context are not suited for land uses that would foster high volumes of pedestrians crossing from one side of the street to the other. • Parkway design is better matched to land uses that depend on vehicle accessibility; types of uses may include regional or community malls, industrial or office parks, and some types of office/mixed-use/multi-use centers. Once the high level of pedestrian activity is developed roadways should be oriented away from the Parkway design. • Local Office/Commercial Streets will apply to developments ranging from very pedestrian-oriented retail locations (similar to Main Streets) to business parks. The goal is to create a convenient and safe network of well-designed streets. Residential Uses (High Density) • Avenues • Local Streets • Avenues provide access from neighborhoods to other areas and infrequently through neighborhoods • Local Streets provide direct access to sites or land uses. Predominant land use along Local Residential Streets will be either single family or multi-family housing, with a full range of possible densities. Residential Uses (Low Density) • Avenues • Local Streets • Avenues provide access from neighborhoods to other areas and infrequently through neighborhoods. • Local Streets provide direct access to sites or land uses. Predominant land use along Local Residential Streets will be either single family or multi-family housing, with a full range of possible densities.

53 Road Function Charlotte’s Urban Streets Design Guidelines define five street types that overlay atop existing classifications as the North Carolina DOT moves away from the traditional thoroughfare planning process. The terminology used and the way in which street types are presented in the guidelines, without specific reference to the FCS, is a new classification scheme for the street network. The five street types defined in the design guidelines are: • Main Streets are “destination streets” that provide access to and function as centers of civic, social, and commercial activity. Main Streets are designed to provide the highest level of comfort, security, and access for pedestrians. Development along Main Streets is dense and focused toward pedestrian traffic. Because of their specialized function and context they represent a relatively small portion of Charlotte’s street network. • Avenues serve a diverse set of functions in a wide variety of land use contexts, providing access from neighborhoods to commercial areas, and occasionally through neighborhoods. Avenues are the most common (non-local) street type in Charlotte serving a collector/connector function. • Boulevards are designed to move larger volumes of vehicles as through traffic. Maintaining vehicular movement is a higher priority than with an Avenue, but safe travel for pedestrians and cyclists is still included in the design. • Parkways are the most auto-oriented of the street types. Their primary function is to move motor vehicles within the city and region; parkways are also one of the least common street types in the City of Charlotte. • Local Streets are the most common street type and provide access to residential, industrial, or commercial districts, as well as to mixed-use areas. Local streets have low vehicle volumes and provide safe travel for pedestrians and bicyclists. The guide outlines multiple cross-section designs to accommodate the range in local street right- of-way widths and adjacent land uses. Relationship to FHWA Functional Classification With the exception of Avenues and Local Streets, none of the streets types described in the guidelines have an explicit function akin to the FHWA classification (Table 8). The descriptions provided and the delineation of auto- and pedestrian-oriented street types suggest that Parkways

54 and Boulevards are similar to arterials, while Main Streets combine aspects of local and collector classifications. Table 8 Charlotte Guide and FCS relationship FHWA Functional Classification Charlotte Urban Streets Design Guidelines Street Types Main Street Avenue Local Street Boulevard Parkway Primary Arterial Secondary Arterial Collector Local Modal Considerations The Charlotte guidelines emphasize that streets are to be evaluated based on how they serve different groups, including motorists, pedestrians (and transit riders), transit operators, bicyclists, and people who live/work or use adjacent land. Guidelines describe the primary design expectations and design elements of each modal group (Table 9). Additionally, the guidelines acknowledge the conflicting expectations of user groups and suggest some design elements that can be used to alleviate these conflicts within reasonable limits to maintain safety.

55 Table 9 Roadway design expectations and design elements by user group User Group Roadway Design Expectations Design Elements Developed to Address Expectations Motorists • Minimal travel delays • Minimal conflicts (affecting both delay and safety) • Consistently designed facilities • Adding through or turn lanes to increase capacity/reduce delay • Make operational changes, including providing more green signal time to streets with higher traffic volumes • Reducing the wait time at signalized intersections for those motorists on higher volume streets • Constructing grade-separated intersections and roundabouts, rather than signal or stop controlled intersections, limits motorist delay and increases traffic flow • Bus pullouts to separate stopping transit vehicles from the travel lane and help reduce delay • Turn lanes separate turning vehicles from the through traffic to potentially reduce rear-end collisions • Medians separate opposing traffic streams • Greater sight distances to “see and be seen” • Street lighting to improve overall visibility • Clear zone adjacent to the outside travel lane provides a measure of “forgiveness”, should a vehicle actually leave the travel lanes Pedestrians • Short walking distances • Separation (or buffer) from moving traffic • Aesthetically pleasing surroundings and amenities • Protect from the elements • Walking is as safe as possible • Short blocks with marked intersections • Safe mid-block crossings on longer blocks • Continuous walkway systems that connect door fronts with transit stops or other destinations • Pedestrian Buffers: Planting strips Bicycle lanes Landscaping On-street parking • Street lighting and pedestrian scale lighting • Increasing pedestrian visibility from adjacent land uses (by placing windows/doors/“eyes on the street”) • Managing driveway access to minimize and control the locations of turning cars • Provide median pedestrian refuge islands or curb extensions, to break up crossings into more easily manageable parts • Reduce the number of travel lanes to reduce overall travel distance • Smaller curb radii • Provide sufficient signal timing so pedestrians don’t feel “trapped in an intersection.” • Aesthetic Design: Benches Trash receptacles Landscaping Urban design for adjacent development Transit Operators • Enough space to operate and maneuver their vehicles • Minimal conflicts with other travelers and with features along the sides of the street • Minimal travel delays, to help keep route operating on time • Wide travel lane • Wide corner turning radii • Street signs, utility poles and on-street parking located to maximize clearance for side mirrors • Adequate merging distances. • Safe locations for bus stops • Provide signal priority for transit vehicles at intersections

56 Table 9 (continued) Roadway design expectations and design elements by user group User Group Roadway Design Expectations Design Elements Developed to Address Expectations Transit Riders • Accessible bus stops • Easy transfer connections • Personal comfort and security while waiting for the bus • Street and pedestrian-scale lighting • Transit stop locations that are not isolated from land uses and other people • Increased visibility through urban design (windows and doorways that face onto the street) Bicyclists • Well-connected network of bicycling facilities • Safe travel routes • Direct travel routes • Particularly when bicycling for work, shopping and errands • Space to maneuver 5’ lane width preferred 6’ lane minimum next to parked cars or on an uphill slope • Designated bike lanes • Pavement markings • Street lighting • Bike boxes and bike signals at intersections • Buffers from travel lanes and parked cars Stakeholders of Adjacent Land Uses (Context Relevant) • Lighting • Safe and contained travel ways • Driveways (for access to their properties) • Trees and landscaping • Site design (commercial properties) • Traffic calming devices • Low design speeds • Safe and convenient pedestrian crossings • Reduced street widths • Stakeholders typically: Oppose access controls (limiting driveways) Oppose median Want Turn Lanes Want Median Breaks to provide access to commercial properties • Site Design Elements: Direct sidewalks to the street Sidewalks between buildings Sidewalks to parking areas • Sidewalk amenity zones • High quality street furnishings Street types are highly correlated with modal considerations in the guide, although no modal hierarchies are outlined specific to either context or functional classifications. The guidelines present a spectrum of pedestrian-oriented to auto-orientation of the street types shown in Figure 21.

57 Figure 21 Modal orientation of street types Design Elements Once the street types are defined for a corridor, the key design control is employed. Surrounding land use context is only employed to define block lengths and creek crossings, and for distinctions between residential and office/commercial uses along local streets. The guidelines also define overlays such as the natural street and creek network. Incorporating the historical and existing stream network with land use contexts operates as a design control with respect to the crossings and block spacing. Regular intervals for creek crossings are outlined in Table 10. Typically, creek crossings should occur with the same frequency as pedestrian and bicycle crossings. In most areas this is at an interval of no more than 1300 feet. Table 10 Land use contexts for creek overlay The guidelines are specific about the design elements to be incorporated by street type. This includes explicit design elements that should not be incorporated into streets. Table 11 describes

58 the priority design elements, design elements to consider, and inappropriate design grouped by street type. Design elements are further partitioned for intersections according to street type. Table 11 Street types and design elements for roadway segments Street Type Priority Design Elements Appropriate / Other Design Elements to Consider Inappropriate Design Main Street • Posted Speed: 25 mph • Design Speed: 25 mph • Number of Lanes: 2, 3 with intermittent turn lanes/median • Lane Width: 13 feet • Sidewalk Clear Zone: 10 feet • Sidewalk Amenity Zone: 8 feet (not including sidewalk) • On-Street Parking: 7 feet • Curb Extensions at Mid- Block Crossings • Pedestrian Scale Lighting • Block Length: 400 feet • Traffic Calming • Mid-Block Pedestrian Crossings • Angled Parking • Medians, minimum 6 feet • Median Planting • Bus Stops/Bus Zones along segments Short block lengths so stops should be located at intersections • Bike Lanes Low operating speeds and wider mixed travel lanes • Planting Strips • Driveways • Pedestrian Refuges Avenues • Posted Speed: 25 - 30 mph • Design Speed: 30 - 40 mph • Number of Lanes: 2 - 4 3 or 5 for intermittent turn lanes / landscaped islands • Lane Width: 11 feet • Bicycle Lanes: 4 – 6 feet • Sidewalk Clear Zone: 6 feet minimum • Planting Strips: 8 feet • Bus Stops: Higher Volume local + express services • Curb Extensions at Mid- Block Crossings • Street Lighting • Pedestrian Scaled depending on surrounding land use • Block Length: 600 feet maximum • Medians, minimum 16 feet • Median Planting • Medians as Pedestrian Refuges • On- street parking: 7 feet • Curb Extensions where there is on-street parking • Curb Extensions at Mid- Block Crossings • Minimize Driveways • Mid-Block Pedestrian Crossings • Sidewalk Amenity Zone: 8 feet (not including sidewalk) • Traffic Calming • Shoulders

59 Table 11 (continued) Street types and design elements for roadway segments Street Type Priority Design Elements Appropriate / Other Design Elements to Consider Inappropriate Design Boulevard • Posted Speed: 35 - 40 mph • Design Speed: up to 45 mph • Number of Lanes: 4 • Medians, minimum 17 feet • Median Planting • Bicycle Lanes: 4 – 6 feet • Sidewalk Clear Zone: 5 feet minimum • Planting Strips: 8 feet • Street Lighting • Pedestrian Scaled depending on surrounding land use • Block Length: 1000 – 1200 feet • Pedestrian Refuges • On- street parking: 7 feet • Double tree rows • Driveways • Utilities placed underground • Bus Stops: Higher Volume local + express services • Mid-Block Pedestrian Crossings • Traffic Calming • Sidewalk Amenity Zone • Shoulder • Curb Extensions Parkway • Posted Speed: 45 - 50 mph • Design Speed: up to 55 mph • Number of Lanes: 4 – 6 • Lane Width: 11 – 12 feet • Medians, minimum 20 feet • Median Planting • Shoulder • Separated shared use path for walking / bicycling: 10 feet • Sidewalk Clear Zone: 5 feet (constrained conditions) • Planting Strips: 8 feet • Street Lighting • Pedestrian Scaled at bus stops or on separated path • Block Length: ½ mile • Bus stops with pull-outs Utilities out of pedestrian / bicycle clear zones • Driveways • Bicycle Lanes (not along shared use paths) • Sidewalk Amenity Zone • Curb Extensions • Traffic Calming • Mid-Block Pedestrian Crossings • Pedestrian Refuges Local Residential Streets • Posted Speed: 25 mph • Design Speed: 25 mph • Number of Lanes: 2 • Lane Width: 12 - 14 feet • Sidewalk Clear Zone: 5 - 8 feet • On-Street Parking: 7 feet • Curb Extensions at Mid-Block Crossings • Street Lighting • Bus Stops • Planting Strips • Swales (storm water management) • Driveways • Traffic Calming • Block Length: based on land use context • Medians, minimum 8 feet • Median Planting • Sidewalk Amenity Zone • Pedestrian Refuges • Curb Extensions • Bike Lanes • Shoulder • Mid-Block Pedestrian Crossings

60 Table 11 (continued) Street types and design elements for roadway segments Street Type Priority Design Elements Appropriate / Other Design Elements to Consider Inappropriate Design Local Commercial Streets • Posted Speed: 25 mph • Design Speed: 25 mph • Number of Lanes: 2 • Lane Width: 12 feet • Sidewalk Clear Zone: 5-8 feet • On-Street Parking: 7 feet • Curb Extensions at Mid-Block Crossings • Street Lighting • Bus Stops • Planting Strips • Driveways • Traffic Calming • Block Length: based on land use context • Sidewalk amenity zone • Medians, minimum 8 feet • Median Planting • Pedestrian Refuges • Curb Extensions • Bike Lanes • Shoulder • Mid-Block Pedestrian Crossings Local Industrial Streets • Posted Speed: 25 mph • Design Speed: 25 mph • Number of Lanes: 2 • Lane Width: 12 feet • Sidewalk Clear Zone: 5 feet • On-Street Parking: 8 feet • Planting Strips • Driveways • Street Lighting • Block Length: 1000 feet maximum • Bus Stops • Traffic Calming • Mid-Block Pedestrian Crossings • Sidewalk Amenity Zone • Medians • Median Planting • Curb Extensions • Bike Lanes • Pedestrian Refuges • Shoulder For all street types a typical cross section of design elements has been created (Figure 22 - 24). Figure 22 Main street typical cross section

61 Figure 23 Avenue typical cross section Figure 24 Boulevard typical cross section Strengths and Weaknesses The Charlotte Urban Street Design Guidelines developed a new classification scheme for urban streets and contained detailed design elements and typical cross-sections for the new street types proposed. The street type overlay terminology was used to avoid conflicts with state guidance. The strength of the guidelines lies in modal priorities being located along a spectrum of street types, and not based on the context the street segment resides in or the roadway function. Further, clear descriptions of expectations and design elements are needed to create an ideal roadway experience for each user group; this offers a unique way to address multimodal design conflicts and community context. The key weakness of the guidelines may be that they leave little room for flexible interpretation. There is also no mention of applying them to non-urban contexts.

62 City of Chicago Complete Streets Chicago was created in 2013 by the Chicago Department of Transportation to implement the city's complete streets policy. It involved a major restructuring of the agency and its project delivery process. The organization is part of a multi-pronged action agenda, which included Sustainable Urban Infrastructure Guidelines, Streetscapes Design Guidelines, Make Way for Play Guide, Bike Lane Design Guide, Tools for Safer Streets Guide, Chicago Pedestrian Plan, Streets for Cycling Plan 2020, Bike 2015 Plan, and 2015 Sustainable Chicago. More information can be found at www.chicagocompletestreets.org. Complete Streets Chicago addresses functional classification through the use of typologies. A typology is a categorization or naming scheme. For example, arterial, collector, and local are types. The Chicago system uses two sets of types for each street, one describing its roadway form and function and the other its building form and function. These are essentially the link and place attributes of any given street. Complementing the roadway and building form and function are a system of overlays. These are generally planning-level categories describing the various statutory, operational, and planning categories that impact design decisions. The number of overlays is open-ended and could be tied to a transportation master plan, zoning, economic development, community, or other efforts. There is a fourth category in Complete Streets Chicago that describes intersections and crossings, but it is not necessarily salient to functional classification. Context Definition Complete Streets Chicago uses the following seven types to categorize street context: Neighborhood Residential, Neighborhood Mixed-Use, District Center or Corridor, Downtown, Institutional or Campus, Industrial, and Parks and Open Space (Table 12). As mentioned above, this is referred to as the building form and function. They describe a street’s land use, urban design, community, and place characteristics. Types are modeled on the CNU Transect system. They are somewhat density based, but not necessarily. Rather, they reflect building types. For example a campus has a similar relationship to the street, whether it is a university, hospital, or housing. Each generally has a main entrance and a perimeter fence. Downtown refers to any sort of high-density building and use. A street segment could have one or two place categories (e.g., if the land use on either side of the street is different).

63 Table 12 Complete Streets Chicago context definition Typology Name Characteristics Typical Zoning Districts Neighborhood Residential • Single-family houses • Low-density multi-family buildings • Non-residential uses such as schools and churches RS, RT Neighborhood Mixed- Use • Buildings with service and commercial uses on the ground floor that serve surrounding neighborhoods • Residential or office uses above the ground floor RM, B1, B2 District Center or Corridor • Concentration of commercial uses that draw from a large area • May be stand-alone commercial buildings • May be part of mixed-use buildings RM, B2, B3, C1, C2 Downtown • High-rise mixed-use, residential, or office buildings centrally located within the city DR, DS, DC, DX Institutional or Campus • Large-scale development (2+ acres) under unified control and organized like a campus • Typically surrounded by gates and controlled-access PD Industrial • Manufacturing, wholesale and industrial uses • May be organized into a campus or industrial corridor • Requires accommodation for large trucks. C3. M2, M3, PMD Parks and Open Space • Intentional open spaces such as parks, forest preserves, and bodies of water • Street entirely within or bordering a park • Park-like medians POS Road Function Complete Streets Chicago uses the following six types to categorize street function: Thoroughfare, Connector, Main Street, Neighborhood Street, Service Way, and Pedestrian Way, which are referred to as the roadway form and function (Table 13). They describe throughput, access, mobility, and operations. The first four types closely resemble the FCS class designations. Service Ways (which are essentially alleys) and Pedestrian Ways (promenades, walkways, paths, and greenways) are not typically considered in a functional class system, but are important network elements in Chicago. Generally, a street segment has only one function type.

64 Table 13 Complete Streets Chicago road function types Typology Name Definition Characteristics Thoroughfare • Widest right-of-way • Raised medians • May have side medians, green space, large sidewalks • Serves through and local functions • Not generally commercial Lanes 4+ Target Speed 25-30 mph Blocks 660-1320 feet ADT 20k and higher Flow 2 way Connector • Main roads • May have median • Connects urban centers • May be commercial Lanes 2 to 4 Target Speed 20-30 mph Blocks 300-660 feet ADT 5-25K Flow 1 or 2 way Main Street • Serves mostly local traffic • Connects neighborhoods and commercial areas • May be commercial Lanes 1 to 3 Target Speed 15-20 mph Blocks 150-300 feet ADT 3-15k Flow 1 or 2 way Neighborhood Street • Almost all local traffic • Serve residential areas • No centerline or lane striping required Lanes 1 Target Speed 10-20 mph Blocks <300 feet ADT <6k Flow 1 or 2 way Service Way • Narrow roadway • No sidewalks • Provides a short service link between two streets Lanes 1 Target Speed 5-10 mph Blocks NA ADT NA Flow 1 or 2 way Pedestrian Way • Pedestrian passageway or walkway • Not necessarily along a typical roadway • Pedestrian access between buildings Lanes NA Target Speed NA Blocks NA ADT NA Flow NA Relationship to FHWA Functional Classification Complete Streets Chicago addresses the relationship between its typology system and the FCS. It states that coding projects by their functional class is required for federal funding, and it provides a conversion table (recreated in Table 14). The agency intends to use this to maintain project funding from state and federal sources.

65 Table 14 Complete Streets Chicago and FCS relationship Modal Considerations Complete Streets Chicago uses modal hierarchies to inform design and operation decisions. There are a multitude of decisions made during the life of a project — from project selection to lane width to signal timing to restriping — and establishing a hierarchy ensures that the decision made supports the complete streets effort. Examples of hierarchies are listed in Table 15. Freight is not listed because it is cross-modal — goods are delivered in Chicago by rail, truck, bike, and on foot. Table 15 Complete Streets Chicago modal hierarchies Default Along a major transit corridor Along a bicycle priority street In an industrial corridor Pedestrian Transit Bicycle Automobile Transit Pedestrian Pedestrian Pedestrian Bicycle Bicycle Transit Bicycle Automobile Automobile Automobile Transit Design Elements Complete Streets Chicago uses design trees to collate mode hierarchy and typology (function and context) and derive cross-sections. Figure 25 demonstrates this process for a pedestrian-priority street in a downtown context. Depending on the function of the street, a particular cross-section is derived (see next section).

66 Figure 25 Complete Streets Chicago design tree for pedestrian mode priority and Downtown Complete Streets Chicago contains precise language on cross-section elements, intersections, and geometric/operational policies, some of which is tied to the classification schemes described above. In general, travel lanes should be 10 feet wide, with an 11-foot lane allowed for a truck or bus route. Narrower lanes are encouraged on Main Streets, Neighborhood Streets, and Service Ways. Lane widths are as follows: • Thoroughfare: 10-11 feet; • Connector: 9-11 feet; and • Main Street: 9-10 feet. Target speeds (equal to or less than the speed limit) are as follows: • Thoroughfare: 25-30 mph; • Connector: 20-30 mph; • Main Street: 15-25 mph; • Neighborhood Street: 10-20 mph; and • Service Way: 5-10 mph. Design vehicles are listed as per the typology of the receiving street:

67 • Thoroughfare: WB-50; • Connector: BUS-40; • Main Street: SU-30; • Neighborhood Street: DL-23 (a new design vehicle based on a United Parcel Service P-80 truck); • Service Way: DL-23; and • Right/left turn on red is to be limited from 6 AM to midnight along streets with the Pedestrian (P) Streets or Bicycle Priority Street overlay. Cross-section dimensions are listed for Thoroughfares, Connectors, Main Streets, and Neighborhood Streets; however, they are not dictated. "Project managers are charged with developing cross-sections which respect the hierarchy and typology." There is a discussion on assemblage — the art of adding, subtracting, and combining widths to arrive at a complete street and examples given that: • The target auto/bike shared lane is 14 feet. • The combination of travel and parking lanes next to one another should be no less than 18 feet (11-foot travel and 7-foot parking or 10-foot travel and 8-foot parking. Table 16 Complete Streets Chicago assemblage table for Thoroughfare

68 Overlays Complete Streets Chicago uses a series of overlays to capture external information related to street design. Overlays could be anything from state route designation to routes identified on master planning documents, to historic designation (Table 17).The thinking is that practitioners benefit when all considerations for a particular street are assembled in one place. At the beginning of a project, the project manager would assemble all of these overlays into one GIS map. The requirements of each overlay would then influence design decisions. A street segment could have none, one, or many overlays (for example a street can be a state route, truck route and transit- priority street, or a street could have no such designation).

69 Table 17 Complete Streets Chicago overlays Typology Name Source Discussion State Route Illinois DOT Approximately 37 percent of Chicago’s major roadways are under state jurisdiction. This limits the city’s ability to control and maintain its street network. An inter-agency directive provides guidance on when and how to use jurisdictional transfer for such streets. County Route Cook County Most county highways within the city fall into one of two categories: 1) county jurisdiction maintained by the city, and 2) municipal extensions of county highways that are under city jurisdiction. Chicago DOT (CDOT) effectively controls these streets; coordination with the County is often a formality. Truck Route Chicago DOT CDOT maintains a GIS layer of truck routes. In additional to being designated as a truck route, there should be at least 5% multiple-unit truck traffic. Snow Route Chicago DOT There are two types of snow routes in Chicago: 1) where parking is restricted from Dec 1 to April 1, and 2) where parking is restricted when 2” or more of snow accumulates. Snow plowing is planned for and accommodated on these routes. Strategic Regional Arterials (SRAs) Chicago Metropolitan Agency for Planning, Illinois DOT Streets designated to carry higher volumes and speeds as a complement to the expressway system. Parking and traffic signals are restricted. It is questionable whether SRAs conform to the City's complete street policies. Mobility Priority Streets Chicago Zoning Ordinance Connect commuter rail stations with the downtown employment core. Section 17-4-0600 of the Chicago Zoning Ordinance designates Mobility Streets and requires 14’ sidewalks to accommodate special pedestrian movement needs. Pedestrian Priority Street (P-street) Chicago Zoning Ordinance Sections 17-3-0500 and 17-4-0500 of the Chicago Zoning Ordinance designate Pedestrian Streets for Chicago’s best examples of pedestrian- oriented shopping streets. Curb cuts are not allowed and other building design standards (setbacks, window transparency) are also required. Bicycle Priority Street (bicycle spoke route, signal timing for bikes) (proposed) Chicago DOT CDOT will identify select corridors where cycling will be prioritized ahead of other modes, which will influence the modal hierarchy and subsequent design. Transit Priority Street (BRT) (proposed) Chicago DOT, Chicago Transit Authority CDOT & CTA will identify select corridors where transit will be prioritized ahead of other modes, which will influence the modal hierarchy and subsequent design. Historic Boulevard System Chicago Housing & Economic Development Chicago’s historic boulevards are listed on the National Register for Historic Places and are a defining characteristic of the city’s street network. Transit-Oriented District (El stops) (proposed) Chicago DOT, Chicago Transit Authority, Chicago Housing & Economic Development These areas require special considerations for riders who arrive on foot, by bicycle, bus or taxi. The City has a working group to formally zone these areas. Home Zone (shared street) (proposed) Chicago DOT Home Zone is a new type of street to be developed by CDOT. It is a residential street, maybe with some commercial, that uses physical traffic calming techniques to slow vehicles to walking speed. Typically it is a shared space with no separation between modes.

70 Strengths and Weaknesses The main strength of Complete Streets Chicago is that it is written from a practitioner’s standpoint, and is currently being integrated into the agency’s operations. Similar efforts to date have been somewhat esoteric and lacking in detail. This document is very precise in its details and applications. While the document is detailed, it is not prescriptive. Indeed, it challenges designers to produce streets that meet the overarching priorities of the agency, and in this instance, complete streets. This is a performance- or metric-based model. Other efforts are either too prescriptive (often listing minimum standards, which then become the maximum depending on the proclivity of the practitioner), or completely neglect critical details. Specific to functional classification, the document plainly states how it intends to refocus street design away from functional classification: "Historical focus on roadway characteristics such as traffic volume, speed and functional classification does not always yield complete streets. Using typologies inverts this approach: design decisions are informed by roadway context and by a hierarchy of mode prioritization, switching the “burden of proof” for design from traffic measurements and functional classification to place making and community preferences." The main weakness of the document is that it lacks the visualizations found in more recent efforts, and it is too "inside baseball" for many to appreciate its value. ITE-CNU Designing Walkable Urban Thoroughfares The ITE, in a joint effort with the Congress for New Urbanism, developed a recommended practice in 2010 called Designing Walkable Urban Thoroughfares as a tool for designing urban streets that are compatible with and supportive of the surrounding context and community. More information can be found at http://library.ite.org/pub/e1cff43c-2354-d714-51d9-d82b39d4dbad. Designing Walkable Urban Thoroughfares introduces a design framework based on the idea of context zones and identifies a set of thoroughfare types consistent with the diverse characteristics found in urban areas. Context zones are used to categorize urban development patterns into discrete ranges of density and intensity of development. Context is defined both by the design of the thoroughfare itself and the adjacent buildings, land use types, and surrounding district. Thus, a thoroughfare’s design may change along its length as context changes.

71 Context Definition Designing Walkable Urban Thoroughfares uses context zones to describe the physical form and character of a place. This includes the intensity of development within a neighborhood or along a thoroughfare. Context zones are applied at the community level, but for the purposes of thoroughfare design, they are interpreted on a block-by-block basis to respond to specific physical and activity characteristics. A total of seven context zones are defined: four within the urban context (including suburban and low-density urban fringe uses), two within the rural context (though it is noted that these are not the focus of the effort), and a district category (to be assigned as applicable). Figure 26 graphically represents context zones, and Table 18 provides detailed written descriptions. Context zones are proposed as an important determinant of basic design criteria in traditional urban thoroughfares. They meant to refine the “rural” and “urban” classifications that are critical for selecting design criteria in the Green Book (AASHTO, 2011). Figure 26 Development continuity

72 Table 18 Context Zone description

73 Road Function Thoroughfare type is the primary driver of design in Designing Walkable Urban Thoroughfares. It governs the selection of the thoroughfare’s design criteria and, along with the surrounding context, is used to determine the thoroughfare’s physical configuration. Design criteria and physical configuration address which elements are included in the design and selection of dimensions. Seven thoroughfare types are identified, however, the primary focus of the guidance is: • Boulevard — Walkable, medium speed (35 mph or less), divided arterials. • Avenue — Walkable, low to medium speed (25-35 mph) collectors or arterials. • Street — Walkable low speed (25 mph) streets serving direct property access. These thoroughfare types typically serve a mix of modes, including pedestrian, bicycle users, private motor vehicles (for passenger and freight) and transit. Table 19 describes thoroughfare types commonly used in the United States.

74 Table 19 Thoroughfare type description Relationship to FHWA Classification Designing Walkable Urban Thoroughfares maintains the FCS, but serves in a secondary role compared to design criteria established using thoroughfare types. Table 20 shows the relationship between thoroughfare types and the FCS. In general, boulevards serve an arterial function, avenues may be arterials or collectors and streets typically serve a collector or local function in the network.

75 Table 20 Thoroughfare and FCS relationships Modal Priorities Designing Walkable Urban Thoroughfares does not explicitly prioritize modes within the corridor; it identifies the roadway and street side/frontage elements recommended for each thoroughfare/context zone category. It recognizes that all elements may not be accommodated within a given right-of-way and provides guidance accordingly. A series of cross sections are presented, organized as per the following four scenarios: 1. Optimal conditions — sections without right-of-way constraints that can accommodate all desirable elements; 2. Predominant — representing sections of the predominant right-of-way width in the corridor that accommodate all of the higher-priority elements; 3. Functional minimum — representing a typically constrained section where most of the higher priority elements can be accommodated; and 4. Absolute minimum — representing severely constrained sections where only the highest-priority design elements can be accommodated without changing the type of thoroughfare. Design Elements Design elements for thoroughfare types are identified and provide a range of operating speeds, number of lanes, and modal considerations (Table 21). The overall focus of the approach is not on establishing a prescriptive design element list. Rather, it attempts to describe context sensitive design approaches to meet the overall objectives of projects. The proposed design process

76 consists of the five stages shown in Figure 27. While this report simplifies the process into five discrete stages, the thoroughfare design process is an iterative one that requires collaboration with the public, stakeholders, and a multidisciplinary team of professionals. Table 21 Design elements by thoroughfare type

77 Figure 27 Thoroughfare design stages Strengths and Weaknesses The principal strength of Designing Walkable Urban Thoroughfares is its expansion of the context zones beyond the existing binary urban/rural definition, and the expansion of the roadway design elements to include street side design. However, it does not entirely address rural contexts or all roadway categories. The design approach of Designing Walkable Urban Thoroughfares is unique in that it moves past prescriptive design elements and instead focuses on a comprehensive design approach based on a context sensitive design/solutions framework. This is further reinforced by the identification of design elements within different constrained environments, highlighting ideal, constrained and minimal thoroughfare designs. While these can serve as starting points for the design process, and modal priorities can be inferred from the design elements characterizations, they may not provide guidance on critical issues, such as when one mode or activity must be prioritized over another due to community requests or some other contextual need.

78 Massachusetts The Highway Division of the Massachusetts Department of Transportation (MassHighway) revised its statewide design policy manual in 2006. This was driven in part by recognition of the agency’s challenges in developing projects for a variety of community contexts. The Project Development and Design Guide (2006) takes a different approach to functional classification from the conventional model of associating classes with design controls, advising designers to tailor project design to actual project needs by use of the project development process and not to rely on a single set of design controls for a given functional class. More information can be found at http://www.massdot.state.ma.us/highway/DoingBusiness WithUs/ManualsPublicationsForms/ProjectDevelopmentDesignGuide.aspx. Context Definition MassHighway’s Project Development and Design Guide delineates context based on level of development and surrounding land uses. Distinctions between community contexts (referred to as “area types”) are made based on built form with a particular focus on building setbacks and property frontages (Table 22). As a result, the MassHighway guide identifies a more diverse range of land use contexts, from low-intensity rural environments to highly dense, highly populated urban areas (illustrated in Figure 28).

79 Table 22 MassHighway area types and community contexts Environmental Context Area Types Land Use Considerations Built Form Considerations Rural Natural • Forest • Farmland • Open Spaces Rural Village • Low intensity – Commercial – Civic Uses – Mixed Uses • Frontages generally less than 200 feet • Right-of-way constrained by built environment Rural Developed • Low-density residential • Infrequent commercial activity • Large setbacks • Significant tree cover of property frontages Suburban High Density • Commercial strip development • Low density residential • Large setbacks for commercial development • Residential frontages less than 200 feet Village/Town Center • Moderate density – Commercial – Residential – Mixed Uses • Uniform building setbacks • Residential frontages less than 200 feet • Right-of-way constrained by built environment Low Density • Low density – Residential – Infrequent commercial • Residential frontages more than 200 feet Urban Urban Park • Open space Urban Residential • High density Residential • Common building scale • Common setbacks (flush frontages) Central Business District • High density Mixed Use

80 Rural Suburban Urban Figure 28 Area types and built form illustrations The guide stipulates that area types be selected before choosing a design based solely on roadway type. Context is the primary influence over the types of modal considerations and the corresponding design elements to include in order to meet activity needs for each mode.

81 Road Function MassHighway’s Project Development and Design Guide employs the FCS designations, referred to as roadway types. They are based on a facility’s role in the state and regional transportation system. The six types include: • Freeways are primarily for interstate and regional travel (high regional connectivity at high speeds with limited access to adjacent land and limited access for pedestrians and bicyclists). • Major arterials service statewide travel as well as major traffic movements within urbanized areas or between suburban centers (high regional connectivity at a wide range of speeds, and a lower level of local access than roadway types that occupy a lower spot on the hierarchy). • Minor arterials link cities and towns in rural areas and connect major arterials within urban areas (high to moderate regional connectivity at a wide range of speeds, and moderate degrees of local access). • Major collectors link arterial roadways and provide connections between cities and towns (moderate to low regional connectivity at a wide range of speeds, and higher degree of local access than arterials and freeways). • Minor collectors connect local roads to major collectors and arterials (lower regional connectivity at lower speeds and higher degrees of local access than the previous roadway types). • Local roads and streets are not intended for regional connectivity (low speeds with a high degree of local circulation and access). Relation to FHWA Functional Classification The MassHighway guide outlines a functional classification scheme that is practically a one-to-one conversion of the FHWA classification system, although it also sub-classifies collectors (Table 23).

82 Table 23 MassHighway and FCS relationship MassHighway Project Development and Design Guide Freeways Major Arterials Minor Arterials Major Collectors Minor Collectors Local Roads & Streets Interstate Freeway/ Expressway Primary Arterial Secondary Arterial Collector Local Modal Considerations Modal needs beyond vehicular traffic are considered but not prioritized in MassHighway’s Project Development and Design Guide (Table 24). For example, while natural rural areas are likely to have little commuter or daily pedestrian travel, users may be attracted to low-volume roadways for scenic travel or recreation. Emphasis is placed on accommodating all roadway users and determining early in the process the composition and expected volumes of different users.

83 Table 24 Additional modal considerations and likely volumes / activity Area Type Additional Modes Considered Corresponding Volumes / Modal Activity Rural Natural • Pedestrians • Bicyclists • Transit • Low • Low • Infrequent if at all Rural Village • Pedestrians • Bicyclists • Transit • High compared to other rural area types • Low – activity within Village • Infrequent if at all Rural Developed • Pedestrians • Bicyclists • Transit • Moderate • Low – though more than Natural areas • Infrequent if at all Suburban Low Density • Pedestrians • Bicyclists • Transit • Moderate – more than Rural Developed • Moderate – more than Rural Developed • Infrequent Suburban Town Center • Pedestrians • Bicyclists • High compared to other suburban area types • High compared to other suburban area types Suburban High Density • Pedestrians • Bicyclists • Transit • Low to Moderate (if facilities are present) • Low to Moderate (if facilities are present) • Low Urban Park • Pedestrians • Bicyclists • High due to path network • High due to path network Urban Residential • Pedestrians • Bicyclists • Transit • High • High • High Central Business District • Pedestrians • Bicyclists • Transit • High • High • High, due to high capacity transit and intermodal hubs Design Elements Design elements are not linked to roadway type within MassHighway’s Project Development and Design Guide. It states that classification serves as a starting point, but designers should not let it be the sole design control. The guide accentuates other key decision points during project development that define design parameters for a project. The selection of design elements is to take place through consultations with community members, users, and project reviewers to “determine the roadway characteristics and appropriate design considerations to serve both the regional purpose of the roadway and its role in the local setting.” There is one specific link between community context and design speed. The guide encourages designers to attentively consider context when selecting the speed. Minimum design standards are outlined for pedestrian and bicycle infrastructure, however, they are not directly associated with functional classifications or specific contexts. The purpose of these standards is to help designers identify best practices when a roadway serves additional modal needs.

84 Overlays MassHighway’s Project Development and Design Guide contains overlays for parkways, historic boulevards, and access control. The guide defines parkways as a unique roadway type. It is essentially an overlay on arterial function classes. The distinction of parkways is largely due to the presence of urban highways that pass through large parklands in major cities, such as Boston. Parkways can also include historical boulevards established under the Boulevard Act of 1894. Access control is influenced by roadway type and area type, although it can be designated based on local statues, zoning, and right-of-way purchases on existing roadways. The overlay of the existing regulations with respect to access control is typically the product of • Statutory control that limits access only to public road crossings on a rural or urban arterial highways. • Zoning regulations that control roadway adjacent property developments so that major generators of traffic will not develop — these regulations are at the discretion of the local government. • Driveway regulations that control the geometric design of an entrance, driveway spacing, and driveway proximity to public road intersections. Strengths and Weaknesses MassHighway’s Project Development and Design Guide expands upon the place-based contexts of urban, suburban, and rural designations to develop a nuanced approach to land use context and the built environment. Associated with each area type is the acknowledgment that pedestrian and bicycle travel must be taken into account, even in less populated rural areas that are not usually considered amenable to multimodal access. The guide refers directly to the FCS and does not propose an alternative, although it does indicate that roadway designers should not use this as the primary means of selecting design controls.

85 Minnesota DOT Minnesota DOT is in the process of developing a Guide based on a revised classification. Its aim is to aid planning and design. Currently, the Guide is 80% developed and the information presented here reflects this status. The complete guide is expected in 2017. Minnesota DOT’s goal was to develop a document that could help designers and planners deliver projects that address the Complete Streets concepts that Minnesota DOT adopted in 2013. The Guide identifies a set of principles that emphasize a process-driven approach and that rely on CSS concepts. Its core principles center on the importance of taking a multimodal approach to address modal needs, using a collaborative framework to promote inter-agency coordination, using a place/context approach to define the uniqueness of each location, and considering network connectivity with an “across and along” approach. In an effort to address these issues, the Guide redefines context and road typology. Context Definition Context areas are defined in Minnesota’s guide based on land use, building form, and frontage type. These variables exist along a continuum. Context areas include: Large Urban Downtown, Urban Commercial Corridor, Urban Residential Area, Industrial Area, Suburban Town Center, Suburban Commercial Corridor, Suburban Residential, Small Downtown or Main Street, Rural Transition Area Agricultural or Rural, and Natural or Recreational. Each context is defined based on qualitative descriptions of land use, building form, and typical frontage type (Table 25). The guide also recommends that designers and planners observe that roadway context changes over the length of a corridor, and that a project should be designed in accordance with the area so that the road aligns with its spatially variable characteristics.

86 Table 25 Context definition criteria and values

87 Road Function Minnesota’s guide recognizes the main problems with the FCS. Classification does not always reflect the roadway context or the need for multimodal considerations. The guide develops a new set of road typologies that is correlated with the existing classification system (Table 26). The description applied to each roadway type is based on facility type, level of access control, and overall function and purpose. Two Arterial types are defined: Urban and Suburban. Each has a slightly different definition, with Urban Arterials incorporating consideration of pedestrians and bicycle use. These categories can be used to bridge the difference between the roadway types, as defined by the guide, and the FCS. Table 26 Roadway categories The proposed road categories are intended to correlate to the context of the area to define the various roadway types. This system is currently under development (Figure 29).

88 Figure 29 Matrix of context and road types Design Elements The Minnesota guide identifies a list of key principles that designers should be mindful of when developing alternative solutions. These include prioritizing community values, understanding the corridor users, selecting the lowest reasonable targeted operating speed and design vehicle, allocating space to most vulnerable road users, beginning with the smallest number of lanes with the smallest dimensions, and taking stock of how operations vary across the day. The guide includes a set of values for typical cross-sectional elements to inform design where ranges for the values are provided (Table 28).

89 Table 27 Typical dimension for cross section elements The guide discusses some potential impacts of modal choices on each design element. Figure 30 illustrates possible trade-offs among the modes, which affect cross section design decisions.

90 Figure 30 Example of alternative cross section choices

91 A central concern of the guide is the selection of desired (target) operating speed. The underlying idea behind this concept is to design a roadway so that its physical design will influence the speed of vehicles. There is discussion about the need for selecting this speed and how its choice will affect the design element values selected in order to achieve the desired operating speed. The Guide also has a section dealing with design flexibility and how selection of design values can address context and road typology without providing specific values to be used. Modal Considerations Minnesota's guide addresses multimodal concerns by evaluating modal importance on a per segment basis. Project corridors are divided into contextual and road type segments and the relative modal importance for each segment is assessed using a slider scale (Figure 31). The importance of each mode is defined based on land use context (Table 25) transportation context (i.e., road typology, Table 26), community importance, modal plans, network linkages, existing conditions, and existing use. Figure 31 Example of relative modal importance Strengths and Weaknesses A key strength of Minnesota’s approach is its classification scheme that expands the definition of context so it is not restricted by a binary choice of urban/rural. The addition of nine categories that redefine suburban, urban and rural contexts, and small urban town, provides additional contexts that could facilitate improved contextual designs. Another strength of the proposed system is the development of a conversion table between the FCS and roadway types. This enables the

92 continued use of the current system in various areas (as needed) while providing additional flexibility that accounts for the varied needs of roadway types. The pictorial matrix, which is still being developed (Figure 29), will correlate context with road types and provide visual clues to identify the context and roadway environments, which is another critical strength of the system. Contextualizing modal considerations on a per segment basis is another strength of the proposed classification because it considers modal choices at the micro-level and bases them on particular segment needs. At this point, there are no identified weaknesses of the proposed approach. NACTO Urban Street Design Guide NACTO developed the Urban Street Design Guide (USDG) in 2013. The guide is touted as a blueprint for designing 21st-century streets where people can walk, bike, drive, park, take transit, and socialize. Divided into six chapters, the guide focuses on types of streets; street design elements including lane widths, sidewalks, and curb extensions; interim design strategies such as parklets and temporary street closures; types of intersections; intersection design elements such as crosswalks and pedestrian islands; and design controls, the criteria used to measure a street’s success. The guide provides case studies from around the country as well as implementation tools. More information can be found at http://nacto.org/usdg/. The NACTO USDG captures an important truth of street design: "classification schemes, in and of themselves, are rarely adequate as a design tool for the diversity of situations to be encountered on city streets." Functional classification propagates the use of auto-centric, highway- based design controls such as design speed, horizontal curvature, and stopping sight distance. Most city streets exist in much more complex environments. Their rights of ways may be fixed. Competition for curb space defies the throughput-access axis. Walking, cycling, transit, freight, and driving networks overlap and intertwine. Streets are used differently at different times of the day, week, and year. The challenge is to develop a workable system, which serves as an extension of a city's goals such as "safety, economic growth, development, and urban design." Context Definition The NACTO USDG states "context is a crucial, yet often overlooked, parameter in designing streets. Street design should both respond to and influence the desired character of the public realm." It does not posit a context-specific classification system for urban streets; however, it includes a catalogue of streets. Each street type is described based on their context and function — i.e., their location, what they contain, and their primary uses. The USDG includes

93 recommendations related to each street type, with transition steps described for some. The 13 street types, along with selected recommendations, are listed below. Illustrations of some of these are shown in Figure 32 and 33. • Downtown 1-Way Street — accept peak-hour congestion in exchange for on-street parking, dedicated transit lanes and protected bike lanes. • Downtown 2-Way Street — encourage off-peak freight delivery. • Downtown Thoroughfare — add a central median. • Neighborhood Main Street — perform a road diet. • Neighborhood Street — add raised crosswalks. • Yield Street — ensure that sidewalks are privileged over driveways. • Boulevard — add trees. • Residential Boulevard — convert central median into park space. • Transit Corridor — add bus rapid transit. • Green Alley — add rain gardens and other storm water management devices. • Commercial Alley — facilitate deliveries by hand truck or bike. • Residential Shared Street — introduce chicanes and other traffic calming devices. • Commercial Shared Street — utilize street furniture to demarcate walking path. In addition to these 13 street types, the guide samples other context categories: Commercial, Industrial, Residential, City, Town, Village, Campus, Cultural, Institutional, Center, Corridor, District, Downtown, Low-Density, Marketplace, Mixed-Use, Neighborhood, Park, Urban, and Workplace.

94 Figure 32 NACTO Downtown and Neighborhood street types

95 Figure 33 NACTO Residential street types Road Function The NACTO USDG embeds function into the respective street types. As described below, the guide offers a wealth of design guidance that is not specific to a particular street type. Instead this guidance is general enough that it can be applied to most streets and street intersections. The thought behind this philosophy is that contexts and functions overlap so much on city streets that design concepts apply everywhere. The guide also samples a number of classification systems used by cities: Avenue, Boulevard, Street, Arterial, Collector, Local, Alley, Lane, Main, Connector, Major, Multi-Way, Thoroughfare, Transit, Auto-Oriented, General, Multi-modal, Parkway, Paseo, Pedestrian, Shared, and Slow. Modal Hierarchy The NACTO USDG has multimodal origins. It contains many recommendations to consider how a particular design or operation decision affects all modes. Highlights include: • On signalization: "use signal priority tools, such as leading pedestrian intervals, synchronized signals for bicycles, or transit signal priority along corridors with established or desired modal priority." • On design hour: "Collect multimodal data over 2–3 hours of peak traffic activity to better understand how traffic behaves through an entire rush-hour period." • On multi-modal level of service: "A street with low “person delay” is not necessarily a great street..." The NACTO USDG mentions that many cities have developed street classification systems and that some use overlays. This is where one would discuss modal priorities, special uses, and historic designations. It samples a number of overlays used by cities: Country Route,

96 State Route, Sanitation Route, Snow Route, Truck Route, Ceremonial, Economic, Historic, Scenic, Bicycle Priority, Driving Priority, Pedestrian Priority, Transit Priority, Home Zone, Pedestrian District, and Transit-Oriented. Design Elements The NACTO USDG offers a number of recommendations for design elements. They are generally not tied of street function or context. Highlights include: • 10-foot travel lanes, with 11-foot for truck or bus routes and 9-foot in select locations. • 7 to 9-foot parking lanes. • 5 to 7-foot pedestrian through zones on residential sidewalks; increase to 8–12 feet in commercial areas. • No clear zones adjacent to the travelled way. • Extensive use of curb extensions. • Judicious use of traffic calming devices such as speed tables, chicanes, and mini- roundabouts. • Pedestrian safety islands on streets with three or more lanes. • Minimal corner radii, based on design speeds (Figure 34). "A large corner radius should not be used to facilitate a truck turning from the right lane into the right lane." • Reduce speeds at intersections with insufficient sight distance. • Shorter signal cycles. • Understand safety implication of speeds (Table 28). Figure 34 NACTO Guide corner radius

97 Table 28 NACTO Guide design speed implications Design vehicles are tied to street type. The DL-23 (a new design vehicle) is recommended for Neighborhood and Residential Streets. The SU-30 is recommended for Downtown and Commercial Streets. The WB-50 is suggested for designated truck routes. The BU-40 is suggested for designated bus routes. Strengths & Weaknesses The main strength of the NACTO USDG is that it advances progressive design guidance. It is unabashedly geared toward city streets and does not bend to highway engineering orthodoxy. Whether its guidance can be transferred to an alternative classification scheme remains an open question. Oregon The Oregon DOT adopted a Highway Design Manual in 2003 that used additional classifications beyond urban, suburban, and rural to define roadway context. The agency mainly focused on urban highways and arterials. The breadth of land use designations has been retained in the agency’s still- current 2012 manual, with specific guidance for design based on a variety of community context types for both state designated urban highways (defined under the 1999 Oregon Highway Plan [OHP]) and non-designated highways and arterials. The main purpose of the context types is to recognize the role of access in roadway design, irrespective of whether the principal purpose of the roadway is focused on access or mobility. More information can be found at http://www.oregon.gov /odot/hwy/engservices/pages/hwy_manuals.aspx#2012_English_Manual.

98 Context Definition Crucial to defining context for urban (non-freeway) highways and arterials is assigning the OHP and urban growth boundary overlay designations, described under Overlays. Developed in 1999, the OHP defined long-range transportation policies and funding strategies for Oregon’s State Highway System. Highways detailed in this earlier plan are referred to as OHP-Designated Urban Highways. All highways and arterials not designated under OHP have different contextual design. OHP Designated Urban Highways The Oregon Highway Design Manual defines three place contexts for OHP-Designated Urban Highways: Special Transportation Areas (STAs), Urban Business Areas (UBAs), and Commercial Centers (CCs). Each designation is qualified by critical factors in land use and transportation dynamics that a designer should consider. The manual underlines the importance of including pedestrian, bicycle, and transit-friendly features in the overall roadway design for STA-specific projects. The UBA designation refers primarily to auto-oriented commercial corridors within state- designated urban growth boundaries. Roads that fall under this heading need to balance moving through traffic with providing access to properties. The CC designation is applied to regional-scale commercial land use areas with limited land use access but direct connection to a regional mobility network – typically, commercial development at freeway interchanges (Figure 35). Figure 35 Intersection of Contexts along OHP Designated Urban Highways within the Urban Growth Boundary (UGB)

99 Non-designated Highways & Arterials For non-designated OHP urban highways and arterials the context categories are: • Downtown / Central Business District — densely urbanized areas with closely spaced buildings. They may look similar to STAs but have not been designated as such by the Oregon Transportation Commission. • Developed Areas — areas where much of the land adjacent to the roadway is developed at urban intensities and only a few parcels are vacant. • Urban Fringe / Suburban — areas that lie between the urban growth boundary and more developed areas. Road Function The Oregon Highway Design Manual does not propose an alternative classification system. The manual’s focus is on highways and arterial roadways within urbanized areas and adapting design standards to the surrounding land use and environmental context. Relationship to FHWA Functional Classification The classification system is nearly identical to the FCS with additional designations for major and minor collectors (Table 29). Local roads are not mentioned and this is likely due to the fact that State DOTs do not typically have jurisdiction over local roadways. Table 29 Oregon DOT and FCS relationship Oregon DOT Highway Design Guide Interstate Expressways Highways Principal Arterials Minor Arterial Major Collector Minor Collector Interstate Freeway / Expressway Primary Arterial Secondary Arterial Collector Modal Considerations Modal priorities are not explicitly stated in the Oregon Highway Design manual. However, considerations for multiple modes are an aspect of each design context. For example, the required

100 design standards for each context include a sidewalk with a minimum width of six feet. Wider facilities are required in more densely urbanized areas. The manual recommends using wider shoulders or bicycle lanes in place of roadway shoulders for all contexts. A separated bicycle facility is required for arterial roadways in Urban Fringe/Suburban Areas. Further, the manual strongly recommends ensuring access to and circulation of transit. Design Elements Design elements for non-interstate highways and arterials are based on contextual definitions alone. Design elements outlined include: • Design speeds; • Lane widths; • Median widths; • Bicycle facilities; • Sidewalk widths and separated sidewalks (buffer zone of planting/landscaping); • On-street parking and dimensions; and • Left or right turn banks. Figure 36 illustrates the design requirements for an urban business area. Figure 36 Urban business area design elements

101 The nodal nature of CCs precludes defining roadway design elements; rather the focus of the manual is on internal circulation of vehicles, bicyclists, and pedestrians. The manual states that CCs should be planned and developed to ensure the following: • Convenient circulation within the center, including pedestrian and bicycle access and circulation. • Provisions for transit access in urban areas planned for fixed route transit service. • Shared parking and a reduction in parking to accommodate multimodal elements where alternate modes are available. • A high level of regional accessibility. Overlays Key overlay distinctions in Oregon’s manual are the Urban Growth Boundaries and the OHP. In 1973, the Oregon Legislature adopted the first statewide urban growth boundaries. For each major city, the urban growth boundary restricts commercial and intensive residential development to these boundaries so that natural resources and agricultural land are preserved. Highways and arterials within the Urban Growth Boundary are the focus of urban highways in the manual. The OHP designated specific state highways for long-term planning and funding strategies in 1999. These highways will have their context defined using the Special Transportation Area, Urban Business Area, and CCs classifications. Other overlay distinctions with a focus on the use of highways include: • Freight Routes; • Scenic Byways with coastal and mountain highways with scenic views; and • Lifeline Routes with emergency routes for high impact earthquakes or flooding. For freight routes, Oregon’s manual discourages reducing design standards and carrying capacity, acknowledging that the transport of goods throughout the state and region is important to local economies. The manual provides a caveat where safety or other modal access requires a reduction in freight vehicle carrying capacities. The manual states that the designation of Scenic Byways and Lifeline routes do not impact the design of urban arterials and highways, with the exception of maintaining structures critical to accessibility for emergency situations on Lifeline routes. However, these structures are not clearly defined.

102 Strengths and Weaknesses Oregon’s system does not deviate from the FHWA’s classification model, with an urban/rural dichotomy of land use designations – although the more expansive set of types and areas promotes flexibility and roadway designs that are more responsive to local needs. Oregon’s unique overlay of urban growth boundaries strengthens the distinction between urban/suburban contexts and rural areas. Additionally, the guide integrates the nuance of nodal activity centers by focusing attention on circulation design considerations for CCs. Functional classification is not the core design control in Oregon’s manual – land use context and existing regulatory overlays are the basis for highway and arterial design. Final design is based on context classifications that rely on regulatory statutes, prior planning, and the existing user base (e.g., current transit corridors) without clearly articulated modal priorities. Pennsylvania and New Jersey DOTs Pennsylvania’s (PennDOT) and New Jersey’s DOTs developed the Smart Transportation Guidebook in 2008 as part of their efforts to implement CSS. Their goal was to develop a document that could assist designers and planners in developing projects that respond to community, environmental, and transportation contexts. PennDOT has adopted the Guidebook as interim design policy guidance. The Guidebook is available at http://www.state.nj.us/transportation/community/mobility/pdf/smart transportationguidebook2008.pdf. The Smart Transportation Guidebook identifies principles that emphasize CSS applications to better define the issues of the project. The principles include the ideas of contextual designs and solutions, multimodal planning, and targeted solutions. As part of complying with these principles, the Guidebook articulates that there is need to improve the definition of project context. The basic idea is to incorporate land use into context definition. Context Definition Context areas are defined according to land use and level of development, which exists along a continuum. Categories include Rural, Suburban Neighborhood, Suburban Corridor, Suburban Center, Town/Village Neighborhood, Town Center, and Urban Core. Critically, even these are defined along a continuum because their boundaries can be fluid. This recognition affects what design elements should be considered. Each context is defined based on quantifiable characteristics such as density level, building coverage, lot size and frontage, block dimensions, maximum height, and minimum/maximum setbacks (Figure 37). The guidebook also recommends that designers and planners consider these using a broad approach, since adhering to a narrow

103 definition of each category may lead to more frequent changes in design elements (recommended minimum length for a context area is 600 feet). When development is planned for an area but has not yet taken place, land use context should be defined based on that anticipated development. Figure 37 Context definition criteria and values For each context, there is a short narrative description that provides details of its characteristics. These are summarized below: • Rural — Few houses, low density, mainly farm land and natural areas, little to no commercial development and population of built-up areas less than 250 people. • Suburban Neighborhood — Low-density housing, neighborhood setting, large lot size, and community facilities (schools, churches, libraries, etc.). • Suburban Corridor — Land use predominantly commercial (big box stores), some housing developments with primary access to frontage roads. • Suburban Center — Mixed-use development (residential, office, commercial retail, etc.), some pedestrian accommodation, and presence of parking areas • Town/Village Neighborhood — Residential neighborhoods, some retail and restaurants, possible street parking, and sidewalks present. • Town/Village Center — Mixed use, high-density area, some parking, and public buildings. • Urban Core — Downtown areas with high density.

104 Roadway Types The Smart Transportation Guidebook recognizes the problems with the FCS. It indicates that according an oversized role to select characteristics (e.g., length, traffic volumes) could result in designs that conflict with community needs or goals. It also addresses the need to distinguish between local and regional travel. A new road typology has been developed that correlates to the existing classification system (Table 30). Table 30 Roadway categories The table provides the basic definition for each roadway type based on operating speeds, trip length, volume and intersection spacing. Critically, there are two community types — Community Arterial and Community Collector. As the table indicates, each is defined on the basis of their unique characteristics. However, the Collector category has two definitions, which are differentiated based on the road type: Community Collector and Neighborhood Collector. These categories can be used to bridge differences between its definition of roadway types and the FCS’s. The proposed road categories are correlated with an area’s context to define the various roadway types and allow for a combination of both elements (Figure 38).

105 Figure 38 Matrix of context and road types Importantly, the proposed typology is an overlay for individual projects and does not replace the FCS. The design values and ranges recommended in the Guidebook are inconsistent with those found in the AASHTO Green Book (Table 32). In addition to the road types noted here, there is a recognition of Main Street as a separate category due to its ability to support more sustainable communities, and because of the potential to increase walking, biking and transit use, and vehicular trip chaining. Characteristics associated with a typical Main Street include wide sidewalks and regular pedestrian activity, mostly commercial and civic uses, high building density, street furniture and public art, heavy use of on- street parking, speeds of 30 mph or less, and preferably no more than two travel lanes, although three to four lanes appear occasionally. Design Elements The guidebook contains a set of suggested values for the various design elements based on the context categories it defines. In general, these follow the values in the AASHTO Green Book, but they reflect greater flexibility and a deeper consideration of the context. Table 31 lists the salient values for arterials.

106 Table 31 Design matrix example

107 There is some discussion about the potential impacts of modal choices on each design element. For example, in determining the lane width, one needs to consider the context area, presence of bus and freight activity, and bicycle treatment. Further discussion covers multiple roadway (lane width, parking lane, shoulder width, bike lane, median, and travel lanes) and roadside (clear sidewalk width, buffer, shy distance, and total sidewalk width) elements. There is also a statement indicating that considering all these elements does not necessarily stipulate they all have to be present at the end, given that balances and priorities must be accounted for as well. The guidebook includes additional design recommendations for specific road types including Main Streets, Industrial Streets, and Rural Crossroads. An issue central to the guidebook concepts is that the operating speed should be a key design constraint. That is, a roadway should be designed so it will be difficult for vehicles to travel above the design speed. There is discussion about the effects of selecting design element values and their influence on operating speeds. This provides a qualitative basis to determine the values that are used when selecting the appropriate operating speed. Modal Considerations The Smart Transportation Guidebook lacks discussion of how modes are specifically addressed within each context. Modes are defined generically during the selection of various design element values (as noted above for the case of lane width choices). The guidebook does not systematically evaluate priorities among modal choices, however, reference to the presence of other modes is implicitly defined in Table 32.

108 Table 32 Cross section elements Strengths and Weaknesses A strength of the Smart Transportation Guidebook lies in its expanding of the idea of context beyond the urban/rural binary. The addition of the suburban categories, as well as town/village corridors, provides additional contexts that could facilitate improved contextual designs. Another strength of the proposed system is it develops a direct relationship between the FCS and roadway types. This allows for the continued use of the current system while providing additional flexibility regarding the varied needs associated with different roadway types. A third strength is the development of a pictorial matrix that correlates context with road types. It also establishes additional visual clues to identify the context and roadway environments. A weakness of the system is its failure to explicitly treat modal issues and its incorporation of design values that require the establishment of modal priorities. The implicit inclusion of the modes in the design element tables is inadequate to accord a role to modes that could require a solution that addresses modal choices. A second weakness is the duplication of the design values

109 from the AASHTO Green Book in the design matrices. The inherent flexibility of the Green Book remains, but the potential tendencies to use the higher ends of the ranges may limit matrices’ utility. Finally, because the classification has not been fully adopted in the DOT’s design manual, it is rendered a somewhat ineffective policy. ADDITIONAL ALTERNATIVE SYSTEMS The six remaining alternative classification systems are briefly summarized in this section. Because these systems address a partial aspect of one of the objectives, a full evaluation is not provided here. Abu Dhabi The Abu Dhabi Urban Street Design Manual, first published in 2010, provides context-based design guidance for all streets in the emirate (a rough equivalent of a state or province), with an emphasis on safety, walkability, and connectivity. The manual drew inspiration from similar urban street manuals in Australia, Germany, the United Kingdom, and the United States. Instead of focusing on motor vehicle throughput, it emphasizes pedestrian comfort. More information can be found at http://www.upc.gov.ae/guidelines/urban-street-design-manual.aspx?lang=en-US. Street families (street types) are defined for each street segment by the surrounding land use context and transport capacity (Table 33). Land use contexts are based on the built environment. Categories include: no active frontage, industrial, residential (1-3 building stories), commercial (1-3 stories), town (3-6 stories), and city (7 or more stories). Transport capacity is defined along two dimensions — vehicle priority and number of travel lanes. After combining this information, street families are generated. Design elements such as operating speeds, pedestrian needs, frontage lanes (access for parking or travel for bicycles and medians), and travel way (roadway) geometry are defined for each street family. Modal priorities are applied to all streets in this order: pedestrians, transit users, bicyclists, and motor vehicles. Priorities are applied to all streets and may contradict distinctions within the transport capacity dimension and therefore, design controls. Non-driving options must be at least as active as private motor vehicle use, irrespective of street type.

110 Table 33 Abu Dhabi street families, transport capacity, and land use context Street Family Transport Capacity Land Use Context Vehicle Priority Travel Lanes City (7stories +) Town (3-6 stories) Commercial (1-3 stories) Residential (1-3 stories) Industrial No Active Frontage Boulevard High 3+3 City Boulevard Town Boulevard Commercial Boulevard Residential Boulevard Industrial Boulevard General Boulevard Avenue Medium 2+2 City Avenue Town Avenue Commercial Avenue Residential Avenue Industrial Avenue General Avenue Street Low 1+1 City Street Town Street Commercial Street Residential Street Industrial Street General Street Access Lane Very Low 1+1 1 shared City Access Town Access Commercial Access Residential Access Industrial Access General Access California California DOT (Caltrans) began developing CSS for highway and arterial roadway design in 2005. Caltrans has focused on design and policy principles for main streets that are “both a community street and a State highway [that] typically have motorized traffic speeds of less than 40 miles per hour and serve pedestrians, bicyclists, transit riders and drivers” (Caltrans, 2014). Caltrans has produced an internal Main Street Listing containing conventional state highways that serve as main street gateways or commercial corridors for community throughout California. The Main Street Listings database specifies opportunities to implement principles and strategies outlined in Main Street, California: A Guide for Improving Community and Transportation Vitality. These opportunities are available to Caltrans staff and are shared with community partners. More information can be found at http://www.dot.ca.gov/hq/LandArch/mainstreet/main_street_3rd _edition.pdf and http://www.dot.ca.gov/hq/tpp/offices/ocp/css.html. Caltrans does not specify modal priorities or hierarchies. Rather, the Main Street program focuses on incorporating complete streets, traffic calming design concepts, and increased livability through multimodal choice grounded in community needs. The guide’s livable street design elements focus on the following principles: • Balanced Main Street Roadways and Intersections that addresses the needs of all modes of travel. • Design for Bicyclists that introduces and improves bicycle access along Main Street corridors.

111 • Design for Pedestrians that elevates the importance of pedestrian and street landscape design while providing access for individuals with limited physical mobility. • Connections to Public Transit that improves transit access along Main Street corridors. • Innovative Devices and Products that pilot new traffic control technologies. All of the design elements and principals outlined in the guide have been incorporated into Caltrans design manuals and standards, including, the Highway Design Manual, State Manual on Uniform Traffic Control Devices, and the Project Development Procedures Manual. The Main Streets program does not propose an alternative classification system; instead, the design guidance is geared toward transforming streets presently classified as state highways by using context sensitive design. The Main Street designation is an overlay on California’s existing functional classification that parallels the FCS class distinctions. Connecticut Connecticut Department of Transportation’s Highway Design Manual closely follows the FCS; however, the manual specifies that the basic urban-rural division of contexts is not sufficiently representative of a highly developed state (like Connecticut). Instead, it uses three area types: built-up areas (the most urban - typically downtowns and other major activity centers), intermediate and suburban areas that are home to less intense patterns of development but still in areas with higher traffic volumes, and rural areas entirely outside of cities and towns (CTDOT, 2003). More information can be found at www.ct.gov/dot/lib/dot/documents/dpublications/highway/cover.pdf, Section 6. The manual specifies the incorporation of distinct cross-section elements based on each area type. For example, principal urban arterials design values differ from those for suburban, intermediate, and built-up area types. The manual lacks specific modal priorities, stating that, “all mobility modes should be considered in the development of project-specific plans” (CTDOT 2003). LA Model Design Manual for Living Streets The Los Angeles County Department of Public Health released the Model Design Manual for Living Streets in 2011. It focuses on all users of the public right-of-way and addresses landscaping, mobility, design, and the public involvement process. Although developed for Los Angeles County, it is intended to provide guidance on a national level. More information can be found at http://www.modelstreetdesignmanual.com/.

112 The manual’s contextual distinctions transcend the typical rural/suburban/urban model by incorporating Transects (see discussion above in 2.3). Because the built form changes along a roadway, a street segment may have multiple Transect classifications. The manual offers a one-to-one translation of the FHWA arterial, collector, and local system: boulevards = arterials, avenues = collectors, streets = local streets. In addition, a fourth category includes alleys and lanes. In proposing these new names, the manual aspires to be more colloquial and less technocratic. Overlays are defined for special streets (main streets, drives, transit malls, bike boulevards, festival streets, and shared spaces) and incorporate modal priorities. Modal priorities focus on non-motorized transportation by recommending maximum block lengths and maximum speeds, regardless of street type. Overlays are also defined for framework and non-framework streets. Framework streets connect neighborhoods, places, and districts, whereas non-framework streets serve as emergency vehicle routes. Traffic calming measures are recommended accordingly. The manual includes recommendations to make streets more lively, beautiful, economically vibrant, and environmentally sustainable, largely through innovative streetscape and roadway edge design. UK Manual for Streets The United Kingdom Department for Transport's Manual for Streets, first published in 2007, offers general design principles that can be applied to smaller streets. It supplements the Department for Transport's Design Manual for Roads and Bridges, a document similar in scope and applicability to the AASHTO's Green Book. More information can be found at https://www.gov.uk /government/publications/manual-for-streets. In the manual, the context and function of streets are defined along two-dimensional hierarchies — place function and movement function. The street types defined using these gradients are: • Motorways – high movement function, low place function; • High streets – medium movement function, medium to high place function; and • Residential streets – low to medium movement function, low to medium place function. Once a road’s status has been established local authorities set objectives for particular sections of a street network and before they select design criteria (design speed, speed limit,

113 roadway geometry, etc.). Modal hierarchy, regardless of movement and place, follows this order: pedestrians, cyclists, public transport users, special service vehicles, and other motor traffic. The manual outlines a process for master planning and the development of context sensitive local design codes. It proposes a fluid functional classification scheme that incorporates place and clearly defines modal priorities. It includes case studies and best practices to implement. A weakness is that its application is at the discretion of local authorities. Vermont Vermont first adopted flexible design standards in 1996 (Keuper, 2002). After the passage of ISTEA in 1991, the Vermont Agency of Transportation (VTrans) undertook an extensive planning process to develop new design standards that better fit the requirements of the federal legislation and the planning goals in the state’s Long Range Transportation Plan — Vermont State Design Standards (1995). With these new standards, VTrans sought to balance economic development with preservation of community character and the natural environment (VTrans, 1997). Standards are likely to be revised in coming years with recommendations to augment and revise the FCS (Smart Growth America, 2015). More information can be found at http://vtransengineering. vermont.gov/sites/aot_program_development/files/documents/publications/VermontStateDesign Standards.pdf. The Vermont standards supplement FCS designations with their proprietary contexts: historic/archaeological sites, natural resources, recreation resources, scenic roadways, and villages and cities. They contain design guidance specific to Vermont (roadway and lane widths, turning radii, landscaping and streetscape elements) and describe conditions for their use. They emphasize flexibility as a key element of the project design process and place responsibility on project managers and designers to determine local context before selecting design controls. They do not specify modal priorities or hierarchies, however. Washington DOT Washington State DOT (WSDOT) is currently developing an alternative classification system to encourage more flexible and context sensitive design solutions. The WSDOT system was inspired by the New Jersey/Pennsylvania DOT Smart Transportation Guidebook. WSDOT, however, modified the land uses categories so they better fit land use patterns found in Washington. Though not complete, the system’s framework has been defined. Context is defined by both a land use category and a subcategory. Land use category is defined as either residential or commercial, while the sub-category uses three density classifications — Rural, Suburban, and Urban.

114 Descriptive characteristics of each land use context category and subcategory division will be developed to appropriately classify roadway segments. Of particular note with the WSDOT alternative is that the goal is to explicitly state defined output for each classification. As such, target operating speed and the accommodated modes will be identified for each transportation category and land use context category/subcategory in the system. This approach enables clear communications about the desired transportation/street performance outcomes without being overbearingly prescriptive regarding the design elements needed to achieve those outcomes. UKY/NN SYSTEM-INDEPENDENT MULTIMODAL CLASSIFICATION ALTERNATIVE The alternative approach developed by the project team envisions that classifications will be developed for each user group or mode — not each roadway. As such, separate classifications may be developed for vehicle thoroughfares, pedestrian activity centers, bicycle routes, transit facilities, etc. The final designation could be selected by layering independent networks together (Figure 39). The designer would then develop the roadway by following these priorities. Defining functional classification and deriving design alternatives for each user function separately will allow for the establishment of a straightforward classification system. Providing separate classifications for each user will also establish priorities for individual corridors, which can then be addressed through design. This classification strategy will assist the designer in distributing design resources when availability is limited. Figure 39 Selection of composite functional classification

115 A combination of this and other strategies could also be used. For example, pedestrian activity could be defined based on adjacent land use, while existing (or proposed) networks could define bicycle, transit, and freight. This concept would function similarly to the overlays used in the Chicago system. One advantage of this system is that parallel routes could prioritize different modes to accommodate users independently. For instance, one parallel route may have narrower lanes, slower design speeds, reduced capacity, and on-street bike lanes, while the other parallel route may use higher capacity thresholds to accommodate higher auto throughput. EVALUATION OF ALTERNATIVE CLASSIFICATION SYSTEMS The next step in this research was to critically evaluate the classification systems described in this chapter to identify which system components hold promise for developing an alternative scheme. The emphasis was on evaluating alternative schemes via context definitions, function definitions (per modal user group), inputs and methods, and impacts on project design. This allowed for a final recommended practice that incorporates the best practices of all systems in a holistic and cohesive manner. To complete this task, a workshop was scheduled with the Working Advisory Group (WAG). Solicitation of the WAG members was through personal contacts, in agencies that have demonstrated activity in the area of FCS. A varied geographical representation was also desired. The participants included the Director of Planning for Kentucky Transportation Cabinet, the Director of CSS for MNDOT, the Director of Design for WSDOT, and the Director for the MPO Ohio–Kentucky–Indiana. The goal of the workshop was to gain perspective from professionals and users of the FCS on existing alternative schemes and what components/elements should be considered for inclusion in a new classification system. The workshop objectives were to: 1) identify and prioritize objectives for an alternative classification system, 2) review current alternative systems, and 3) determine which of the current alternatives most closely align with the identified objectives. The workshop included project team presentations of the NCHRP project objective and work outline, literature review, and preliminary results from the user survey. Objectives for an Alternative Classification System To evaluate alternative classification systems, it is imperative to develop a set of criteria that would be conducive to a systematic evaluation. A set of objectives that an alternative classification system should meet was established. As noted above, the review of alternative systems focused on outlining context definition, the ability to consider and accommodate modal priorities, and

116 impacts of classification on design. These were the initial objectives of the system, and at the workshop the project team presented a preliminary framework of key objectives for additional refinement and evaluation. A facilitated discussion established the primary and subsidiary objectives. After discussion the preferred set of objectives was identified and rank ordered by consensus as follows: Primary • Improved context definition — the group recommended these elementary factors be considered for context definition: density, land use and activity, and access level. • Ability for multi-modal prioritization — the modes to be considered include vehicles, pedestrians, bicycles, and transit. Secondary • Ability to consider system level needs — this refers to the ability of the classification system to communicate the importance of the roadway within the overall transportation system or transportation network. • Ease of use — this concept considers data availability requirements to pursue classification, ability to be straightforward and widely understood, and capability for systematic application. • Ability to differentiate rural and urban applications — this encompasses the requirement that different design elements be used or considered for urban and rural areas, respectively. • Ability to Directly Relate to the FHWA FCS — the existing system should be maintained independently from the proposed system, but it should also be possible go back and forth between systems. The last three secondary objectives emerged during discussion and reflect specific agency needs. For example, having the ability to relate the alternative system to the FCS is a result of the exiting funding structure for a project. Any new scheme should make allowances for these interactions. Current Alternative Systems Evaluation The group was instructed to score each alternative system using a five-point scale (1 = does not meet objective, 5 = exceeds the objective) bearing in mind the primary and subsidiary objectives.

117 After the meeting additional systems were identified and reviewed, and these were presented in the previous sections. The alternatives presented and discussed included: 1. California; 2. Oregon; 3. Massachusetts; 4. Pennsylvania/New Jersey; 5. NACTO; 6. Charlotte; 7. AustRoads; 8. ARTISTS; 9. Design Domains (a project team composite); 10. UKY/NN System; 11. Washington State; 12. Abu Dhabi; and 13. Minnesota. Workshop participants presented the alternatives. During the presentations the systems’ context treatment, design implications, and their various elements were identified. A discussion of the merits and components of each alternative followed each presentation and the WAG members then scored the alternative from 1 (does not meet objective) to 5 (fully meets objective). Scores were tabulated to assess how well the alternative schemes meet each objective (Table 34).

118 Table 34 Scoring of alternative classification systems Alternative Classification System Composite Total Context Definition Modal Priorities Ease of Use Relate to FCS Rural/ Urban Project/ System Pennsylvania/ New Jersey 4.38 3.38 4.31 3.75 2.25 3.25 21.31 Washington State 4.33 3.67 2.33 2.50 3.67 2.67 19.17 AustRoads 3.25 3.06 2.56 3.25 3.31 2.75 18.19 UKY/NN System 2.75 4.38 2.75 2.75 3.00 2.50 18.13 Massachusetts 3.38 2.38 3.25 3.75 3.25 1.75 17.75 California 4.00 3.25 1.69 3.00 3.50 2.13 17.56 Abu Dhabi 4.25 4.88 3.50 1.75 1.00 1.75 17.13 Oregon 4.00 2.00 3.50 3.00 2.50 2.00 17.00 NACTO 3.81 3.81 3.75 1.25 1.25 2.00 15.88 Design Domains 4.00 3.06 2.25 1.00 3.25 2.00 15.56 Charlotte 3.44 3.75 3.50 0.75 1.75 2.00 15.19 ARTISTS 3.50 2.13 2.75 1.88 1.88 2.25 14.38 Minnesota* 4.00 4.00 4.00 4.00 5.00 5.00 26.00 * The Minnesota system was only ranked by one WAG member and is not included in the partial comparisons Table 34 indicates that there is a variety of systems that meet the objectives set forth. The objective of context definition is met best through the Pennsylvania/New Jersey system (first) and Washington State (second). The objective of modal prioritization is best achieved in the Abu Dhabi system and the UKY/NN System. For the secondary objectives, the Pennsylvania/New Jersey system meets the ease of use, ability to crosswalk, and project/system objectives; the Massachusetts system meets the ability to relate directly to FCS and California and Washington State systems meet the rural/urban applications. The highest scoring alternative was the Pennsylvania/New Jersey system. However, it fell short of meeting one primary objective (Modal Prioritization) and one secondary objective (Rural/Urban Applications). The alternative with the second highest overall score was the Washington system. Based on the scoring a best composite alternative would include: • Context Definition — Pennsylvania/New Jersey. • Modal Prioritization — Abu Dhabi and UKY/NN System. • Ease of Use — Pennsylvania/New Jersey.

119 • Direct Relation to FCS — Pennsylvania/New Jersey and Massachusetts. • Rural/Urban Applications — California and Washington State. • Project/System Context — Pennsylvania/New Jersey and AustRoads. Selected Issues and Concerns Voiced During Group Discussion The advisory group meeting was agenda-guided and facilitated, but it was open-ended enough to let members to voice their expert opinions in an unstructured format. Major comments related to the FCS and alternative classification systems were noted. They are summarized below. • More texture is needed so the system can adequately the describe transportation and land use relationship. • Functional class is used in urban areas to determine/qualify for funding. • Land use should be considered in terms of activity and movement to define context. • All roads cannot serve all purposes – right-of-way is too constrained. • State highways become main streets in some rural areas. • Traffic projections do not always consider future densities – land use plans may help. • Sometimes project-level and system-level needs compete with one another. • We deal with simple and complex things; do not be afraid to be complex (if needed). • Should we consider multimodal integration rather than prioritization? • We need to consider generational/cultural change relating to transportation needs. • Functional class does not capture driver expectations or driver perception. • (City) Public works directors dislike functional class and consider it inapplicable to cities. • Functional class is set a decade or more before project (design) is initiated. • We need written descriptions and graphics (pictures/photos) to convey functional class. • We lack modal priorities and ways to determine them. • What is the business case for changing the FCS? – cost savings, safety performance. • There is probably not one existing alternative that meets all needs. • We need more in-depth urban settings and modal consideration in a new system. • Urban spoke/wheel vs. grid system would react differently to the same FCS. • Existing labels carry traditional definitions – fresh names would be would be better. • How can we accommodate transitions and transition areas? • Tables need description and visuals to avoid being taken out of context.

120 Concluding comments from the advisory group members focused on the need for an alternative classification system, what it must achieve and how it might work. The consensus was that none of the alternatives reviewed would suffice in their entirety. Advisory group members agreed that systems which treated the context of the urban and suburban areas more fully were preferable. They also expressed concern that the rural classification needed expansion. The need to include some attention to a hierarchy of modal systems was expressed and specifically the need for modal prioritization in urban areas. A special need to address transitional areas between classification categories was expressed. Generally, it was agreed upon that a hybrid system was called for, and that the typologies needed to be clearly evident and new terminologies possibly adopted. Discussion concluded with a focus on design implications. The need for design guidance using target speeds as well as a table of general design values was discussed. However, members strongly indicated that a thought process of design was most desirable and that a highly prescriptive table would be counterproductive. EVALUATION SUMMARY The various alternatives presented and discussed are summarized in Table 35.

121 Table 35 Summary of alternative classification systems Cl as sif ica tio n Sy st em Ro ad F un ct io n Co nt ex t D ef in iti on Mo da l C on sid er at io ns De sig n El em en ts Ob jec tiv es CD MP EU RF S/ P RU AR TI ST S Fo ur ca teg or ies di vid ed in ar ter ial an d n on - ar ter ial an d i n ro ad s/w ay s a nd st re ets Fiv e c ate go rie s b as ed on ro ad loc ati on (N ati on al, C ity , D ist ric t, Ne igh bo rh oo d, Lo ca l) Us er -b as ed hi er ar ch y o f mo de s c on sid er ing ro ad tra ns po rta tio n f un cti on No de sig n re co mm en da tio ns       Au st Ro ad s Ve ry sim ila r t o U S FC S of ar ter ial , c oll ec tor , loc al sy ste m Si x c ate go rie s b as ed o n l an d us e ( Mo st ru ra l & na tur al; R ur al, ru ra l re se rve ; S ub ur ba n; Ge ne ra l ur ba n; Ur ba n c en ter ; a nd U rb an co re ) Re co gn itio n o f m od es De sig n D om ain to co ns ide r a ll e lem en ts an d fin d a pp ro pr iat e f it f or ro ad de ma nd s       Ch ar lo tte Fiv e c ate go rie s f or ur ba n s tre ets (P ar kw ay s; Bo ule va rd s; Av en ue s; Lo ca l s tre ets ; a nd M ain str ee ts) Si x c ate go rie s b as ed o n l an d us e an d u rb an fo rm (A cti vit y ce nte rs; T ra ns it s tat ion ar ea s; Gr ow th co rri do rs; N on - re sid en tia l u se s; Re sid en tia l; Re sid en tia l L ow -D en sit y Em ph as is on ho w str ee ts se rve us er s a nd m od es wi th de sig n g uid eli ne s f or ea ch m od e De sig n v alu es fo r e ac h co nte xt ca teg or y w ith dis tin cti on be tw ee n p rio rity ele me nts an d e lem en ts to be co ns ide re d; lis ts of ina pp ro pr iat e e lem en ts ar e p ro vid ed       Ch ica go Si x c ate go rie s f or ur ba n s tre ets (T ho ro ug hfa re ; Co nn ec tor ; M ain st re et; Ne igh bo rh oo d s tre et; Se rvi ce w ay ; a nd Pe de str ian w ay ) Se ve n c ate go rie s b as ed on la nd us e a nd ur ba n f or m (R es ide nti al; Mi xe d- us e; Co mm er cia l c en ter ; Do wn tow n; Ins titu tio na l o r Ca mp us ; In du str ial ; a nd P ar ks ) Mo da l h ier ar ch y i s co ns ide re d b as ed on mo da l c or rid or an d de sig n d ec isi on s a re ba se d o n d es ign de cis ion tre es w he re ch oic es ar e ma de ba se d o n m od al pr ior itie s De sig n e lem en ts tie d t o the cl as sif ica tio n s ch em e an d b as ed on th e d es ign de cis ion tr ee s t ha t d efi ne typ ica l c ro ss se cti on s       IT E - CN U Se ve n c ate go rie s (F re ew ay /E xp re ss wa y/ Pa rkw ay ; R ur al hig hw ay ; B ou lev ar d; Av en ue ; S tre et; R ur al ro ad ; a nd A lle y/R ea r lan e) Se ve n z on e c ate go rie s b as ed on ch ar ac ter , b uil di n g e lem en ts, fro nta ge ty pe an d p ub lic sp ac e (N atu ra l; R ur al; S ub ur ba n; Ge ne ra l u rb an ; U rb an ce nte r ; Ur ba n c or e; an d A ss ign ed dis tric t) Re co gn itio n o f m od es ; n o ex pli cit ac co mm od ati on De sig n e lem en ts ar e co ns ide rin g o pe ra tin g sp ee ds , n um be r o f la ne s an d m od al co ns ide ra tio ns       No tes : CD : C on tex t d efi nit ion ; M P: M od al pr ior itie s; EU : E as e o f u se ; R F: R ela tio n t o F CS ; R U: R ur al/ ur ba n co ve ra ge  Me ets ob jec tiv e;  P ar tia lly m ee ts ob jec tiv e;  Do es no t m ee t o bje cti ve )

122 Table 35 (continued) Summary of alternative classification systems No tes : CD : C on tex t d efi nit ion ; M P: M od al pr ior itie s; EU : E as e o f u se ; R F: R ela tio n t o F CS ; R U: R ur al/ ur ba n co ve ra ge  Me ets ob jec tiv e;  P ar tia lly m ee ts ob jec tiv e;  Do es no t m ee t o bje cti ve Cl as sif ica tio n Sy st em Ro ad F un ct io n Co nt ex t D ef in iti on Mo da l C on sid er at io ns De sig n El em en ts Ob jec tiv es CD MP EU RF S/ P RU Ma ss ac hu se tts Tr ad itio na l cla ss ific ati on sy ste m of ar ter ial , c oll ec tor , loc al Ni ne co nte xt lev els ba se d o n l an d us e a nd ur ba n f or m (U rb an Ce ntr al Bu sin es s D ist ric t; Ur ba n re sid en tia l; U rb an pa rk; S ub ur ba n hig h d en sit y; Su bu rb an vil lag e/t ow n c en ter ; S ub ur ba n l ow de ns ity ; R ur al de ve lop ed ; R ur al vil lag e; an d N atu ra l) Mo da l c ho ice s a re co ns ide re d f or ea ch co nte xt an d ac co mm od ati on of ro ad wa y u se rs is co ns ide re d No t li nk ed to ro ad wa y typ e a nd de sig ne rs ne ed to co ns ide r t he cla ss ific ati on a s a sta rtin g p oin t; e mp ha sis on se lec tin g d es ign sp ee d c on sid er ing co nte xt       Mi nn es ot a Ei gh t c ate go rie s co rre lat ed to FC S (F re ew ay ; Ex pr es sw ay ; L ow - vo lum e h igh wa y; Ru ra l h igh wa y; Su bu rb an ar ter ial ; Ur ba n a rte ria l; Co lle cto r-c on ne cto r; an d L oc al str ee t- ro ad ) 11 co nte xt ar ea s b as ed on la nd us e a nd ur ba n f or m (L ar ge ur ba n do wn tow n; Ur ba n c om me rci al co rri do r; Ur ba n r es ide nti al ar ea ; Ind us tria l a re a; Su bu rb an to wn ce nte r; Su bu rb an co mm er cia l co rri do r; Su bu rb an re sid en tia l; Sm all do wn to wn or M ain st re et; Ru ra l tr an sit ion ar ea ; A gr icu ltu ra l or R ur al; an d N atu ra l o r Re cre ati on al) Mo da l c ho ice s a re co ns ide re d f or ea ch ro ad wa y s eg me nt alo ng a sli de r s ca le to de ter mi ne the ir i mp or tan ce A lis t o f k ey cr os s s ec tio n ele me nts to be co ns ide re d a lon g w ith a ra ng e o f v alu es to be us ed is pr ov ide d b ut no t tie d t o c las sif ica tio n; se lec tio n o f d es ire d op er ati ng sp ee d c en tra l to ch oic es       NA CT O US DG Ci ty sp ec ific 13 co nte xt lev els ra ng ing fr om do wn tow n t o n eig hb or ho od str ee ts ba se d o n u rb an fo rm Mo da l c ho ice s a re in clu de d in de sig n e lem en ts De sig n r ec om me nd ed va lue s n ot tie d t o s tre et fun cti on or co nte xt       Or eg on FC S of ar ter ial , co lle cto r, loc al Si x c on tex t c ate go rie s b as ed on lan d u se (S pe cia l tr an sp or tat ion ar ea s; Ur ba n b us ine ss ar ea s; Co mm er cia l c en ter s; Do wn to wn ; De ve lop ed ; a nd U rb an fr ing e / su bu rb an ) Co ns ide ra tio ns of m od es ar e a n a sp ec t o f e ac h de sig n c on tex t Ta ble s w ith de sig n va lue s ( ra ng es ) b as ed on co nte xt de fin itio ns       Pe nn sy lva ni a & Ne w Je rs ey Fiv e c ate go rie s ov er lap pin g F CS (R eg ion al ar ter ial ; Co mm un ity ar ter ial ; Co mm un ity co lle cto r; Ne igh bo rh oo d co lle cto r; an d L oc al St re et / R oa d) Se ve n c ate go rie s b as ed on la nd us e a nd ur ba n d en sit y ( Ur ba n co re ; T ow n c en ter ; T ow n/ Vi lla ge ne igh bo rh oo d; Su bu rb an ce nte r; Su bu rb an co rri do r; Su bu rb an Ne igh bo rh oo d; an d R ur al) No sp ec ific m od al co ns ide ra tio ns bu t pr es en ce of m od es is co ns ide re d i n a ge ne ric ma nn er by ro ad wa y fun cti on Ta ble s w ith de sig n va lue s ( ra ng es ) b as ed on co nte xt de fin itio ns      

123 As Table 35 indicates, several systems achieve the objectives identified by the project team and WAG, though in different ways. These differences raise the following discussion points. Multimodal Priorities Several systems meet the objective of balancing multimodal priorities. Some systems, such as both the Pennsylvania and New Jersey DOTs Smart Transportation Guidebook accommodate modes such as pedestrians and bicycles based on the context definition of a road. This can then be balanced with the system-level function of the roadway. Other systems explicitly state a commitment to multimodal priorities, such as Abu Dhabi’s, which places pedestrian priority at the top and vehicle traffic at the bottom. Still others address multimodal needs independently, such as the Chicago and the UKY/NN systems, which designate modal needs street by street according to system needs, or the ITE-CNU system, which discerns modal needs through the community visioning process and CSS design approach. It is clear that a method of establishing modal priorities is necessary to counter the mono-modality of the FCS. Context Definition All elements expand on the existing urban/rural dichotomy to refine further the land use context definition. While some states have chosen merely to define an additional third class of suburban, others expand this practice by including up to 13 different land use contexts. The key to the success of the existing system has been in its simplicity, even though that simplicity still causes confusion regarding the context and function definition of the roadway. Therefore, care must be taken in establishing another system to balance simplicity with the wide range of land uses that are present in the built and natural environment. One must consider not only the various contexts, but also the implied design parameters that may exist completely outside of the normal range of design flexibility. As the review of literature and state practices revealed, a minimum set of contexts for design may be considered as: 1. Rural; 2. Rural Main Street; 3. Suburban; 4. Urban; and 5. Urban Core.

124 Ease of Use Of all the objectives, ease of use was only met by one alternative, the Pennsylvania/New Jersey system. While the total number of new context definitions is significant (7) it was not identified by the WAG as overly burdensome. In addition, the primary driver of its ease of use is its heavy reliance on pictures to relate context and land use/built form environment. While WAG members from various states saw some elements that did not match their landscape, there was a consensus that each picture was successful in defining their specified elements. It will be imperative to provide this level of clarity graphically and descriptively for whichever choice is made. Direct Relation to FHWA Functional Classification System While this was the WAG’s lowest-rated objective, it also had the most split and consternation in determining the way forward. The consensus was that providing a direct link to the roadway classifications of arterial, collector, and local street function either by maintaining the existing nomenclature or by providing a direct relationship between the new and old system would facilitate the implementation and acceptance of the system. However, other members argued that maintaining this relationship would also provide a justification for engineers and planners wanting to preserve the status quo design philosophy associated with the FCS. Thus, when considering implementation, the desired timeframe for adoption should be considered in light of the amount of support that can be garnered from FHWA, AASHTO, and others in affirming this direct link to the existing nomenclature.

Next: Chapter 5. Proposed Functional Classification System »
Developing an Expanded Functional Classification System for More Flexibility in Geometric Design Get This Book
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TRB's National Cooperative Highway Research Program (NCHRP) Web-Only Document 230: Developing an Expanded Functional Classification System for More Flexibility in Geometric Design, which documents the methodology of NCHRP Research Report 855: An Expanded Functional Classification System for Highways and Streets builds upon preliminary engineering of a design project, including developing the purpose and need.

In particular, NCHRP Web-Only Document 230 provides additional contexts beyond urban and rural, facilitates accommodation of modes other than personal vehicles and adds overlays for transit and freight.

Two case studies illustrating an application of the expanded system to actual projects are included.

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