For decades the Transportation Planning Board has made the data and information it collects about the region's transportation system available to the public, including road traffic counts and transit ridership numbers. Now, the TPB is making much of that information available online so that local planners and decision-makers, developers, consultants, and anyone else can access it, after obtaining login information from the site administrator.

The TPB launched its online Regional Transportation Data Clearinghouse in November 2012, following several years of providing most of the same data by request on CD-ROM. The new online tool is intended mainly for technical users rather than the general public, although future changes could make it more accessible to lay audiences. Already the tool features a map-based interface that makes it easier to access data for a specific travel corridor, jurisdiction, or part of the region, and allows users to download customized data sets rather than the TPB's full store of data.

Among the key kinds of information currently available on the clearinghouse site are traffic volumes for most major highways and arterial routes in the region and average weekday ridership for Metrorail, Metrobus, and several other local transit services.

Traffic volumes are currently available for more than 6,500 points along the region's road network. The data comes from actual traffic counts that the TPB performs and from permanent count stations maintained by the state departments of transportation in Virginia, Maryland, and the District of Columbia.

The TPB has collected information on traffic volumes since the late-1960s as a way to monitor changes in roadway use in the region, and for calibrating the models it uses to forecast future travel patterns. The TPB's online clearinghouse is the only place where all of the data for the region is brought together and presented in a uniform way.

Similarly, the clearinghouse site brings together information about all of the different transit services in the region, including detailed route information -- like route origin and destination and frequency of service -- as well as average weekday ridership.

Route information is currently available for nearly 1,770 bus and rail routes, and weekday ridership numbers are available for approximately 80% of those routes. That information comes from Smartrip data, on-board rider survey results, and other methods that the transit providers use to track ridership.

Population and job growth forecasts prepared and maintained by the Metropolitan Washington Council of Governments are also available on the clearinghouse site.

Through its periodic "Cooperative Forecasting" process, the Council of Governments works with local jurisdictions to forecast how much population and job growth will happen in the region in coming decades. The forecasts also show where planners expect that growth to occur, and the clearinghouse maps that information to the level of geography used in forecasting future travel patterns.

All of the data on the clearinghouse site is available for download in formats that allow users to build customized maps using geographic information systems software, or GIS. A user guide spells out the steps for finding data for specific jurisdictions, service providers, or highway segments, and for downloading it in the desired format.

Already, numerous TPB member agencies and organizations have requested access to the site, including the District Department of Transportation and Prince William and Loudoun Counties in Virginia. DDOT staff report that the clearinghouse has aided internal research efforts and has resulted in time-savings in obtaining data gathered by other transportation agencies.

A few consultants doing work on behalf of TPB member agencies have also requested access to the site, including one performing a traffic study of Memorial Bridge for the Federal Highway Administration.

As the TPB works to enhance the online clearinghouse, it expects to make new kinds of data available to users. Capital Bikeshare station locations and ridership data and Metrorail station entry and exit information are on the horizon. Other possible additions include the projects that are in the region's long-range transportation plan and updated population information from the U.S. Census Bureau.

The Transportation Planning Board's new online Regional Transportation Data Clearinghouse provides 24-hour access to the TPB's extensive stores of data on traffic volumes, transit ridership, and forecast growth for the Washington region, making it much easier for those who want to use the data to find it, access it, and download it in the format they need.

Related Links

• Regional Transportation Data Clearinghouse:
  gis.mwcog.org/webmaps/rtdc/
  
  NOTE: You must obtain login information from the site administrator. Instructions are provided on the clearinghouse site.