4 shows the relations between traffic flow density and average momentary speed on arterial streets with free traffic flow at different regulation speed, as well as with different numbers of lanes in different time periods.
When analysing the data acquired on average momentary speeds it was concluded that the actual speeds on arterial streets rarely exceeded the design speeds for arterial streets.
The results of this study serve as the basis for determination of design regulation speed in urban areas on arterial streets with free traffic flow.
This study recommended using high pressure sodium lights (HPS) on collector and arterial streets and low pressure sodium lights (LPS) on residential streets.
After more discussion and presentations by city department staff members, the existing policy of using LPS lighting on residential streets and HPS lighting on collector and arterial streets was reaffirmed.
With nearly 50 miles of arterial streets already illuminated with HPS, it would be extremely difficult to start using LPS without now converting those streets already illuminated with HPS.
* On arterial streets, more LPS poles would be needed since the pole spacing is typically closer with LPS than with HPS.