Arterials and their auxiliary facilities in the rural context should be designed for Level of Service B or better in the design year as defined in the . All other contexts should be designed to Level of Service C or better. Level of Service D may be allowable for heavily developed or constrained areas.

See for more information regarding level of service as it relates to facility design.

Arterials in dense developed urban areas may necessitate the use of Level of Service C or D in the design year.

The describes methodology and applications for level-of-service criteria and capacity for automobiles, as well as pedestrians, bicycles, and transit, for urban street facilities. Urban street facilities as defined as having a length of:

It also provides similar guidance for urban street segments, which are shorter than urban street facilities and allow analysis of more specific locations as needed. The theoretical automobile capacity of a through lane on an urban street facility or segment is 1,800 vph; adjustment factors reduce this capacity to account for the effects of certain roadway characteristics. Refer to the methodology should be used to determine the recommended number of through lanes needed for given conditions on a specific facility or segment.

Where arterials in rural areas pass through a rural town context and non-motorized roadway users are present, or likely to be present in the future, the motor-vehicle level of service may be reduced to provide a more balanced level of service for all modes of transportation.