DOI: 10.3886/icpsr38585.v2
title: National Neighborhood Data Archive (NaNDA): Primary and Secondary Roads by Census Tract and ZIP Code Tabulation Area, United States, 2010 and 2020
title: Version 2

description: This collection contains measures of primary and secondary roads (highways and main arteries) per United States census tract and per United States ZIP code tabulation area (ZCTA) in 2010 and 2020. These measures may be used as a proxy for heavy traffic, high traffic speeds, and impediments to walking or biking. Variables include: counts of primary, secondary, and all streets per tract and per ZCTA; total length of primary, secondary, and all streets per tract and per ZCTA; ratio of primary and/or secondary road counts to all roads; and ratio of length of primary/secondary roads to all streets.
description: In order to investigate the impact of disamenities (Weiss et al., 2011) on neighborhood walkability, this study describes the number and proportion of primary and secondary roads per census tract and ZIP code tabulation area in the United States.
description: The research team used ArcGIS Desktop and the 2010/2020 TIGER/Line all lines (edges) shapefiles for all U.S. counties to identify edges that represented three types of roads: primary roads (limited-access highways with on- and off-ramps and are typically part of the interstate or state highway system), secondary roads (two or more lanes, intersect directly with other roads, and are generally part of a state or county road system), and all streets. Classification of roads as primary or secondary is based on the MAF/TIGER Feature Class Code (MTFCC), a five-character code used to classify features of the landscape and built environment (U.S. Census Bureau, 2016). The team then assigned roads to census tracts/ZIP code tabulation areas (ZCTA) using the TIGER/Line topological faces shapefile.
To create the final datasets, the team aggregated the total number and length of all streets, primary roads, secondary roads, and both primary/secondary roads per census tract/ZCTA, as well as calculated ratios of total primary and/or secondary roads to all streets and length of primary and/or secondary roads to length of all streets.
description: Datasets: 
DS0: Study-Level Files
DS1: Primary and Secondary Roads by Census Tract 2010 Data
DS2: Primary and Secondary Roads by ZIP Code Tabulation Area 2010 Data
DS3: Primary and Secondary Roads by Census Tract 2020 Data
DS4: Primary and Secondary Roads by ZIP Code Tabulation Area 2020 Data
description: Census tracts and ZIP code tabulation areas in the United States, excluding U.S. island territories. Smallest Geographic Unit: census tract and ZIP code tabulation area
description: The data and documentation for National Neighborhood Data Archive (NaNDA): Primary and Secondary Roads by Census Tract, United States, 2010 and National Neighborhood Data Archive (NaNDA): Primary and Secondary Roads by ZIP Code Tabulation Area, United States, 2010 were originally deposited in openICPSR.A ZIP code to ZCTA crosswalk must be used to combine this dataset with ZIP code geocoded data. A crosswalk and sample code for merging the crosswalk with National Neighborhood Data Archive (NaNDA) datasets are available in the ICPSR Linkage Library.Data users interested in walkability and neighborhood disamenities (such as pollution and traffic) might find useful data in these other NaNDA datasets:

Polluting Sites by Census Tract, United States, 2000-2018
Polluting Sites by ZIP Code Tabulation Area, United States, 2000-2018
Street Connectivity by Census Tract, United States, 2010
Street Connectivity by ZIP Code Tabulation Area, United States, 2010
Traffic Volume by Census Tract, United States, 1963-2019
Traffic Volume by ZIP Code Tabulation Area, United States, 1963-2019
Data users interested in other resources that contribute to walkability, such as parks, public transit, and retail and other destinations, may find the following additional NaNDA datasets to be of use:

Arts, Entertainment, and Recreation Organizations by Census Tract, United States, 2003-2017
Arts, Entertainment, and Recreation Organizations by ZIP Code Tabulation Area, United States, 2003-2017
Eating and Drinking Places by Census Tract, United States, 2003-2017
Eating and Drinking Places by ZIP Code Tabulation Area, United States, 2003-2017
Retail Establishments by Census Tract, United States, 2003-2017
Retail Establishments by ZIP Code Tabulation Area, United States, 2003-2017
Parks by Census Tract, United States, 2018
Parks by ZIP Code Tabulation Area, United States, 2018
Public Transit Stops by Census Tract, United States, 2016-2018
Public Transit Stops by ZIP Code Tabulation Area, United States, 2016-2018
For additional information see the National Neighborhood Data Archive (NaNDA).