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Define Rural Area Roads (Task 1)
Pages 4-21

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From page 4...
... • Social and Physical Context: Driver behavior, settlement patterns, local culture, and physical design influence road safety in any given area. A safety-oriented classification system that accurately represents local conditions -- especially one specifically aimed at behavioral countermeasures -- should consider both cultural and physical characteristics that influence safety risk.
From page 5...
... County Typology Codes U.S. Department of Agriculture ERS Six mutually exclusive categories based on economic dependence and six overlapping categories based on policy-relevant themes.
From page 6...
... The nine categories are: – Counties in metro areas with a population of 1 million or more – Counties in metro areas with a population of 250,000 to 1 million – Counties in metro areas with fewer than 250,000 people – Urban population of 20,000 or more, adjacent to a metro area – Urban population of 20,000 or more, not adjacent to a metro area – Urban population of 2,500 to 19,999, adjacent to a metro area – Urban population of 2,500 to 19,999, not adjacent to a metro area – Completely rural or with an urban population of less than 2,500, adjacent to a metro area – Completely rural or with a population of less than 2,500, not adjacent to a metro area Urban Influence Codes (UIC) The UIC system includes 12 categories that consider population, adjacency to a metropolitan area, and the presence of towns and other population clusters that are too small to be considered urban.
From page 7...
... Economic dependence categories include the following: – Farming-dependent counties – Mining-dependent counties – Manufacturing-dependent counties – Federal or state government-dependent counties – Recreation counties – Nonspecialized counties Policy-relevant categories include the following: – Low education counties – Low employment counties – Persistent poverty counties – Persistent child poverty counties – Population loss counties – Retirement destination counties
From page 8...
... Ranging from high-speed and access-controlled Interstates to relatively lowspeed local roads, the functional classification system defines the role a particular roadway segment plays in serving traffic flows through the network (Figure 1)
From page 9...
... . Systems Arising from Safety Analysis Whereas the functional classification system seeks to preemptively sort roads into categories based on their design and intended operational characteristics, safety analysis selects mitigation strategies by considering crashes and their causes retrospectively.
From page 10...
... The research team therefore recommend that these safety analysis components enter into the roadway classification process. Proposed Classification System The following section describes the proposed rural road safety classification system and presents a method for combining area and road categories into a single system to support subsequent tasks.
From page 11...
... • Rural Towns: Not adjacent to a metropolitan area but have an "urban" population of 2,500-20,000 based on Rural-Urban Continuum Codes and UIC. • Remote: Has a population density of less than seven people per square mile or has an Urban Influence Code that defines the county as a non-metropolitan rural area that does not contain a town of at least 2,500 people.
From page 12...
... . First, they filtered out metropolitan counties exceeding specific population or population density thresholds, then assigned the remaining counties in the following order: tribal, agriculture & extraction, older-age, destination, remote, rural towns, micropolitan, and fringe.
From page 13...
... . They also drew from ICMA's Putting Smart Growth to Work in Rural Communities report and NCHRP Report 582 to develop the destination county category (ICMA, 2020)
From page 14...
... 14 Table 3 summarizes key differences among the proposed rural area categories. On the following page, Figure 4 displays the categories spatially.
From page 15...
... % of Total Population Average Population Density (2017 ACS) % of Total U.S.
From page 16...
... 16 Figure 4.
From page 17...
... .7 • The research literature on road safety analysis, including the HSM, does not use separate road classifications. Rather, it extrapolates incident-level risk posed by human and physical factors to estimate segment-level safety outcomes.
From page 18...
... 49.1% 4.1% All Rural Roads 71.2% 30.3% Source: U.S. Department of Transportation The tables on the following pages provide a detailed overview of the functional classification system for rural roads.
From page 19...
... • Provide service to corridors with trip lengths and travel density greater than those served by rural collectors and local roads, with relatively high travel speeds, and minimum interference to through movement. Lane Width (ft)
From page 20...
... Major Collector Minor Collector Local Description Provide service to any county seat not on an arterial route, to the larger towns not directly served by the higher systems, and to other traffic generators of equivalent intra-county importance such as consolidated schools, shipping points, county parks, important mining and agricultural areas. Link these places with nearby larger towns and cities or with arterial routes.
From page 21...
... The research team believed that distinguishing road functional classifications by area type, using the area classification system outlined in the previous section, would incorporate the key physical road safety factors while also including area-dependent human factors likely related to driver behavior. The research team proposed using a combined rural road safety classification system consisting of eight rural county types and seven rural road types for future research tasks (Table 7)


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