D.C. Mun. Regs. tit. 10-A, § 412
412.1 The District's roadway system consists of 1,171 miles of roadway, 241 vehicular and pedestrian bridges, and approximately 7,774 intersections. Approximately 22 percent of these intersections are signalized.
412.2 The roadways in the District are categorized by function, ranging from interstates and other freeways, which carry the largest volumes of motor vehicle traffic, to local streets, which provide the highest level of access to land uses. Map 4.4 shows the existing roadway system based on a Functional Classification System described in Figure 4.3.
412.3 Map 4.4: Roadway System by Functional Classification
412.4 Increases in funding for street maintenance since the mid-1990s have allowed the District to continually improve the condition of its roadway pavement. The District continually monitors and rates the condition of its roadways and bridges.
412.5 Figure 4.3: Existing Roadway System Functional Classification
| Road Type | Description |
|---|---|
| Freeways and Expressways | These roadways, which comprise 54 miles or approximately five percent of the total roadway miles in the District, are controlled access facilities. Access is via interchange ramps and these roadways typically do not provide direct access to adjacent land uses |
| Principal Arterials | These roadways, comprising 92 miles or approximately eight percent of the District's roadway system, typically serve major activity centers and serve longer trip lengths than the roadways types listed below. The freeways and principal arterials the overall roadway system. Freeways and principal arterials typically carry between 40 and 60 percent of the city's total traffic volumes. |
| Minor Arterials | Minor arterials account for 173 miles, approximately 15 percent of the total roadway system. These roadways serve short to medium length trips, with a greater emphasis on mobility than direct access. In a typical network, minor arterials make up 15 to 25 percent of the mileage and carry 15 to 40 percent of total traffic. |
| Collectors | The role of collectors is to move traffic from local streets to the arterials. Collectors will often intersect with arterials at signalized intersections. Local roads will intersect collectors at stop signs. Collectors make up 152 miles, or 13 percent, of the District's roadway system. |
| Local Roads | These roads typically make up the majority of the transportation network as measured by road miles. They carry between 10 and 30 percent of all traffic. The primary role of local roads is to provide access to adjacent land uses, with ideally a very limited role in terms of traffic mobility. Approximately 60 percent, or 682 miles, of the District's roadway system is classified local. |
412.6 Traffic congestion on the District's roadway network occurs primarily on the radial principal arterial roadways. Map 4.5 illustrates motor vehicle traffic volumes on major streets and highways. The flow of motor vehicle traffic is greatly influenced by north-south movements along the I-95 corridor feeding into I-295 and I-395. These highways carry the heaviest daily motor vehicle traffic volumes in the District, with an average of approximately 168,000 daily trips on I-395 and 108,000 on I-295 in 2017. In addition, the limited number of crossings over the Potomac and Anacostia Rivers generates higher volumes of motor vehicle traffic at these gateways than their counterparts in the northern portion of the District.
412.7 Examples of heavy volumes in 2017 from the south include 38,000 daily motor vehicle trips across the Anacostia River on the Pennsylvania Avenue Bridge, 52,000 motor vehicle trips across the Potomac on the Francis Scott Key Bridge, 94,000 motor vehicle trips across the Theodore Roosevelt Bridge, and 241,000 motor vehicle trips across the 14th Street Bridge and I-395 bridge complex, also over the Potomac. These volumes can be contrasted with volumes coming into the
District from the north and northeast, which include 29,000 daily motor vehicle trips on Connecticut Avenue, 21,000 motor vehicle trips on Massachusetts Avenue, 24,000 daily motor vehicle trips on Georgia Avenue, 33,000 daily motor vehicle trips on 16th Street NW, 48,000 daily motor vehicle trips on North Capitol Street, and 132,000 daily motor vehicle trips on New York Avenue.
412.7a
Research shows that urban traffic congestion tends to maintain a self-limiting equilibrium: vehicle traffic volumes increase to fill available capacity until congestion limits further growth. Any time a consumer makes a travel decision based on congestion (“Should I run that errand now? No, I’ll wait until later when traffic will be lighter.”) they contribute to this self-limiting equilibrium. Travel that would not occur if roads were congested but that would occur if roads become less congested is called induced travel demand. Increasing road capacity, or reducing vehicle use by a small group, creates additional road space that is filled with induced demand.
412.8
Map 4.5: Existing District Traffic Volumes, 2017
412.9 As Washington, DC is a densely developed District with a historic built environment, the District does not foresee making significant investments in road widening to accommodate more motor vehicles. Instead, the District will continue to manage existing roadway resources and provide for viable transportation choices throughout Washington, DC.
412.10 As part of moveDC, an analysis of the transportation impacts of anticipated 20-year land use and transportation changes was conducted. The analysis projected that if the recommendations in moveDC are implemented, there will be a 39 percent increase in the total number of transit trips by 2040, a 16 percent increase in the total number of motor vehicle trips, and a 52 percent increase in nonmotorized trips (walk and bike). Motor vehicle congestion will increase on several corridors. The analysis concluded that new TDM measures, bike and pedestrian improvements, and transit improvements will be needed to keep the system functioning adequately.
412.11 Policy T-2.5.1: Creating Multimodal Corridors Transform District arterials into multimodal corridors that incorporate and balance a variety of mode choices, including bus, streetcar, bicycle, pedestrian, and automobiles.
412.12 Policy T-2.5.2: Managing Roadway Capacity Manage the capacity of principal arterials within existing limits rather than increasing roadway capacity to meet induced demand for travel by car (see text box entitled The Concept of Induced Demand). Prioritize improvements based on their multimodal person-carrying capacity. Increase auto capacity on roadways only if needed to improve the safety of all travelers, improve connectivity of the multimodal transportation network, or improve targeted connections to regional roadways.
412.13 Policy T-2.5.3: Road and Bridge Maintenance Maintain the road and bridge system to keep it operating safely and efficiently and to maximize its useful life.
412.14 Policy T-2.5.4: Traffic Management Establish traffic management strategies that prioritize the safety of pedestrian over vehicular traffic; separate local traffic from commuter or through-traffic; and reduce the intrusion of trucks, commuter traffic, and cut-through traffic on residential streets. Prioritize public transit solutions, including bus lanes and signal priority, to reduce commuter traffic.
412.15 Policy T-2.5.5: Natural Landscaping Work with other District and federal agencies to identify, plant, and manage natural landscaping areas along highways, traffic circles, bike paths, and sidewalks.
412.16 Action T-2.5.A: Maintenance Funds Provide sufficient funding sources to maintain and repair the District's system of sidewalks, streets, and alleys, including its street lights and traffic control systems, bridges, street trees, and other streetscape improvements.
Regularly evaluate the need for adjustments to traffic signal timing to prioritize pedestrians, surface transit, and bicyclists.
Continue to update the Functional Classification System on a two-year cycle. The Functional Classification System is a tool developed by the Federal Highway Administration (FHWA) and used by DDOT to help describe and generally assign the vehicular transportation purpose of a street within the street network.
SOURCE: District of Columbia Comprehensive Plan Act of 1984, effective April 10, 1984 (D.C. Law 5-76; 31 DCR 1049 (March 9, 1984)); as amended by District of Columbia Comprehensive Plan Act of 1984 Land Use Element Amendment Act of 1984, effective March 16, 1985 (D.C. Law 5-187; 32 DCR 873 (February 15, 1985)); as amended by District of Columbia Comprehensive Plan Amendments Act of 1989, effective May 23, 1990 (D.C. Law 8-129; 37 DCR 55 (January 5, 1990)); as amended by District of Columbia Comprehensive Plan Amendments Act of 1989 NCPC-Recommended Amendments, and Closing of Public Alleys in Square 669, S.O. 88-452, Act of 1990, effective May 23, 1990 (D.C. Law 8-132; 37 DCR 2213 (April 6, 1990)); as amended by District Government Land Use Temporary Amendment Act of 1994, effective October 1, 1994 (D.C. Law 10-190; 41 DCR 5360 (August 12, 1994)); as amended by Comprehensive Plan Amendments Act of 1994, effective October 6, 1994 (D.C. Law 10-193; 41 DCR 5536 (August 19, 1994)); as amended by District of Columbia Comprehensive Plan Act of 1984 Land Use Amendment Act of 1994, effective March 21, 1995 (D.C. Law 10-235; 42 DCR 30 (January 6, 1995)); as amended by Technical Amendments Act of 1996 effective April 18, 1996 (D.C. Law 11-110; 43 DCR 530 (February 9, 1996)); as amended by Second Technical Amendments Act of 1996 effective April 9, 1997 (D.C. Law 11-255; 44 DCR 1271 (March 7, 1997)); as amended by Comprehensive Plan Amendment Act of 1998, effective April 27, 1999 (D.C. Law 12-275; 46 DCR 1441 (February 19, 1999)); as amended by Technical Amendments Act of 1999, effective April 12, 2000 (D.C. Law 13-91; 47 DCR 520 (January 28, 2000)); as amended by Comprehensive Plan Amendment Act of 2006, effective March 8, 2007 (D.C. Law 16-300; 54 DCR 924 (February 2, 2007)); as amended by Technical Amendments Act of 2008, effective March 25, 2009 (D.C. Law 17-353; 56 DCR 1117 (February 6, 2009)); as amended by Comprehensive Plan Amendment Act of 2010, effective April 8, 2011 (D.C. Law 18-361; 58 DCR 908 (February 4, 2011)); as amended by Comprehensive Plan Amendment Act of 2021, effective August 21, 2021 (D.C. Law 24-20; 68 DCR 006918 (July 16, 2021)).