Protecting your Children with Courtesy Streets
by James MacLeod
There are several options an engineer is presented with when designing the width of a roadway. The option that provides the engineer with the narrowest roadway width possible is called a courtesy street or queuing street. These streets are design to be a two way street with parking on one or both sides and where drivers must pull over closer to the curb in order to let opposing drivers pass by. These situations are called “encounters”. Travel lanes are not delineated (no double yellow centerline) when constructing these types of streets allowing vehicles to use the entire driving zone width. Typical driving zone widths range between 12-18 feet, with one lane of traffic being between 6 to 9 feet in width. These streets provide great safety benefits for to all users (pedestrians, bicylists, and motorists) by forcing drivers to slow down when passing one another and through these delays caused by these encounters reduces the number of vehicles that use these streets as cut through areas. Below are two locations in Somerville, Massachusetts that demostrate the concepts of Courtesy Streets.
|Figure 1: Location Map Of Bailey Road and Governor Winthrop Road, Somerville MA|
|Figure 2: Bailey Road Looking Northwest|
The overall width of Bailey Road from curb to curb is roughly 30 feet. This includes two 7 foot parking lanes on both sides of the street with a driving zone of 16 feet. This 16 feet allows vehicles a comfortable route down Bailey Road. However when a vehcile coming from the opposite direction the drivers must pull closer to the parked vehicles to pass one another. Also by utlizing courtesy streets at this location it discourage cut through traffic through this residential area, when vehicles trying to access Interstate 93 get backed up to this area.
|Figure 3: Governor Winthrop Road Looking Southeast|
Another example of a courtsey street can be see one street over from Bailey Road on Governor Winthrop Road . The overall width of Governor Winthrop Road from curb to curb is roughly 26 feet. This includes two 7 foot parking lanes on both sides of the street with a driving zone of 12 feet. This 12 feet allows vehicles a comfortable route down Governor Winthrop Road, however when vehicles pass one another one vehicle must find an area without a parked vehicle in order to have enough space for the other vehicle to pass one another comfotrabley due to the limited space the lower limit of the driving zone width povides for drivers of 12 feet. Through the use of this courtesy street design, pedesitran who utlize the nearby by Grimmons park along this Road are now further protect by the dangers of vehicular traffic, by forcing drivers to slow down when moving along these narrow streets.