6.1.3 Design Speed
The design speed for collectors can vary greatly between the five contexts.
The design speed should reflect the anticipated target speed during non-peak hours.
However, the design speed should not exceed the limits of prudent construction, ROW, and socioeconomic costs. Minimum design speeds for collectors are shown in
.See
for additional guidance on selecting the appropriate design speed.
When determining applicable radii and superelevation for design speeds see Table 4-3 for a summary of superelevation methodologies to be used.
6.1.3.1 Rural
Design speeds for rural collectors may be reduced to 40 mph or higher in rolling terrain and 50 mph or higher in level terrain for facilities with an ADT < 2,000 VPD. See
for guidance on different types of terrain.
6.1.3.2 Rural Town
Design speeds for collectors in the rural town context may vary from 30 to 45 mph.
6.1.3.3 Suburban
Design speeds for collectors in the suburban context range from 35 to 60 mph and will typically act as a transition segment between rural and urban or rural town sections of roadway.
6.1.3.4 Urban and Urban Core
The design speed for urban collectors should range from 30 to 45 mph. The design speed for urban core collectors should range from 25 to 30 mph.