Annualized count data for the TPB modeled region. Data are collected from state DOTs and processed by TPB staff.Layers IncludedAnnualized Traffic Volumes Historic AADT by Count Station This database contains the Annual Average Daily Traffic (AADT) estimates reported at permanent and short term counting stations in the TPB modeled region. Please note: Interstates in Virginia are typically represented by two stations (one in each direction) while Interstates in the other states are represented by one station. Therefore, the AADT estimates displayed for the stations on Virginia Intestates will be around half of the total for the directional roadway. The AADT estimates for recent years in this file are based on counts taken at the actual count station locations that are indicated by the station points. The AADT estimates for earlier years are based on volumes reported along roadway segments that the station points currently represent. Specific data sources for each state are listed below:District of ColumbiaAADT estimates since 2006 are based on counts taken at the station locations in the file for purpose of Federal HPMS reporting.AADT estimates prior to 2006 are based on Traffic Volume maps produced by DDOT (Formerly DC DPW).MarylandAADT estimates since 2000 are based on counts taken at the station locations in the file and reported by MD SHA.AADT estimates prior to 2000 are based on volumes reported by MD SHA in the Highway Location Reference documents and matched to links in the COG/TPB highway network. The volumes are shown at the count locations that currently represent those network links.VirginiaAADT estimates since 1997 are based on counts taken at the station locations in the file and reported by VDOT.AADT estimates prior to 1997 are based on volumes reported by VDOT in the Average Daily Traffic Volumes documents and matched to links in the COG/TPB highway network. The volumes are shown at the count locations that currently represent those network links.West VirginiaAADT estimates since 1999 are based on counts taken at the station locations in the file and reported by WV DOT.Traffic Counts by Network LinkThis layer was created by assigning the state DOT traffic counting station locations to their corresponding COG/TPB network links. Facility names and route numbers were added to the network. AAWDT Average Annual Weekday Daily Traffic (2010 - 2021) and Count Type (2010 - 2021) are included as well as Count Year (last year the link was counted). Count Type denotes the source of the count. Please note: for bi-directional roads, the AADT and AAWDT values for each location were divided in two and assigned to both network links that represent the Anode-Bnode direction and the Bnode-Anode direction. Therefore, in most cases the AADT/AAWDT values associated with an individual link in this network will be half of the AADT/AAWDT values reported at the associated individual count station point. Traffic Counts by External StationThis layer was created by placing points where major facilities cross the TPB Modeled Area boundary. In some cases, the external station represents more than one facility. The facility field indicates which road or roads the station represents. AADT and AAWDT estimates at external stations are provided for 2007 through 2023. Each external station is assigned to a state DOT traffic counting station(s). An effort was made to assign stations or combinations of stations that would come closest to measuring the traffic volume on each facility as it enters/exits the region. In some cases, these volumes are measured just inside the modeled area; in other cases, the volumes are measured just outside the modeled area. The external stations around the Baltimore Beltway are exceptions to this rule. These stations all measure the traffic just south of the Baltimore Beltway in order lessen the influence of traffic specific to Baltimore. AADT Average Annual Daily Traffic (1986 – 2023) and AAWDT Average Annual Weekday Daily Traffic (2007 – 2023) are included. Count Type denotes when the location was last counted. West Virginia does not report AAWDT, so the AADT values were increased by 5% to arrive at AAWDT estimates in West Virginia.

Average daily traffic count data collected by each district for USDOT FHWA funding or roadways and infrastructure within West Virginia that is segmented by pre-defined mileage points from Federal Highway Administration (FHWA) onto the WVDOT road network. As with the AADT traffic counts, the data is collected in the field by traffic counters (Permanent, Special, or Short Term) by the districts in sent to the Traffic Analysis Section for further analysis and validation. The data is then evented onto the state highway network to create each roadway segment. Information contained in this data set includes station number, route number, route common name (if applicable), federal functional classification, RouteID, Route segment measurement, nearest city, year measured, number of trucks, collection apparatus type, and traffic count. Data is current as of July 1, 2020 and updated annually.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Primary roads are generally divided, limited-access highways within the interstate highway system or under State management, and are distinguished by the presence of interchanges. These highways are accessible by ramps and may include some toll highways. The MAF/TIGER Feature Classification Code (MTFCC) is S1100 for primary roads. Secondary roads are main arteries, usually in the U.S. Highway, State Highway, and/or County Highway system. These roads have one or more lanes of traffic in each direction, may or may not bedivided, and usually have at-grade intersections with many other roads and driveways. They usually have both a local name and a route number. The MAF/TIGER Feature Classification Code (MTFCC) is S1200 for secondary roads.