Description: Annual average daily truck traffic is the total truck traffic volume divided by 365 days. Truck counting is done throughout the state in a program of continuous truck count sampling. The sampling includes a partial day, 24-hour, 7-day and continuous vehicle classification counts. The partial day and 24-hour counts are usually made on high volume, urban highways. The 7-day counts are made on low volume, rural highways. The counts are usually taken only once in the year. About one-sixth of the locations are counted annually. The resulting counts are adjusted to an estimate of annual average daily truck traffic by compensating for seasonal influence, weekly variation, and other variables that may be present. Annual average daily truck traffic is necessary for presenting a statewide picture of truck flow, evaluating truck trends, planning and designing highways and for other purposes. Truck traffic is classified by number of axles. The two-axle class includes 11/2-ton trucks with dual rear tires and excludes pickups and vans with only four tires. Total vehicle AADT for the same year is taken from the Traffic Volumes on California State Highways booklet also published by the California Department of Transportation.Reference Link: http://www.dot.ca.gov/hq/traffops/saferesr/trafdata/index.htm
Copyright Text: California Department of Transportation
Description: This feature class was updated from our 2012 city boundary GIS data by extracting city boundaries from Tax Area Services Section (TASS) of the California Board of Equalization 2013-2015 data release. The city boundary lines were digitized to match available county parcel base information provided from TASS in the format of CAD DWG layers and/or the Tax Rate Area (TRA) maps in PDF file. TIGER/Line Parcel data and ESRI Basemap imagery were used as reference layers. Additional 3 nautical mile offshore polygons were digitized for the coastal cities located from south of San Francisco to the Mexican border according to TRA maps. We keep the offshore polygons separate from their city boundaries on the lands, and put “3 nautical mile offshore” label in the attribute “Notes” for those polygons. The attributes include 2010 United States Census population and land area information, the city incorporated dates and web links are listed as well. This GIS version of California City boundaries is intended for general reference, planning, and study purposes only and does not represent official property boundary determinations.
Copyright Text: Division of Research, Innovation and System Information (DRISI) of California Department of Transportation (Caltrans); Tax Area Services Section (TASS) of the State of California Board of Equalization.