Intersection Markings:

Example of bicycle lane treatment at a right turn only lane.

Illustration from Manual on Uniform Traffic Control Devices

http://www.pedbikeimages.org/ - Shawn Turner
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http://www.pedbikeimages.org/  -  Steven Faust
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Some 50 to 70 percent of bicycle-motor vehicle crashes occur at intersections or other junctions such as driveways. Intersection markings are one method of helping bicyclists negotiate these problem areas. The AASHTO Guide for the Development of Bicycle Facilities discusses recommended placement of bike lane striping for various kinds of intersections.3 The guide also covers special situations where there are high numbers of right-turning motor vehicles and where auxiliary right-turn lanes are needed. Bike pockets may be used to direct bicyclists to the best placement in the intersection. Bike pockets placed next to a roadway centerline may also be used to make it easier for bicyclists to negotiate an offset intersection.

Sometimes dashed lines are used to indicate the proper path for the bicycle in a complex intersection. Colored pavement may also be used for this purpose, as well as to indicate the weaving area for bicycles and motor vehicles when right-turning motor vehicles cross the path of bicycles in a bike lane. The intent is to increase awareness and safe behaviors by both cyclists and motorists and yielding behaviors by motorists.

Other kinds of markings are available for use at intersections. Bike box is the term that has gained popularity in the United States for a European treatment usually known as the advanced stop bar. The box is a right-angle extension to a bike lane at the head of the intersection (see drawing). The box allows bicyclists to get to the head of the traffic queue on a red traffic signal indication and then proceed first when the traffic signal changes to green. Such a movement is beneficial to bicyclists and eliminates conflicts when, for example, there are many right-turning motor vehicles next to a right-side bike lane. Being in the box, and thus at the front of the traffic queue, also tends to make bicyclists more visible to motorists. Recessed stop lines operate similarly. These treatments should only be considered where there are a considerable number of daily bicycle commuters. Multi-lane streets with high traffic volume should be carefully evaluated to be sure the treatment would be safe. (See case study #26.)

Another example is a combination bicycle lane-right-turn lane at an intersection. There are many intersections where using a minimum-width bike lane is not possible due to limited right-of-way. The use of a shared, narrow right-turn lane in combination with a bike lane in a limited right-of-way situation is a novel approach. This treatment could be applied in initial intersection design, when retrofitting a bike lane to an existing right-of-way, and when adding an auxiliary right-turn lane. This innovative application is used in Eugene, OR, to allow straight-through bicyclists to share a narrow right-turn lane with motorists. At the intersection proper, the total right-turn lane width is 3.6 m (12 ft), which includes a bike lane (pocket) of 1.5 m (5 ft) and a 2.1 m (7 ft) space to the right of the bike pocket. Depending on the size of the motor vehicle, the bicycle could be positioned in front of, beside or behind the motor vehicle in this combination lane. (See case study #21.)

The city of Portland, OR, has used special markings to direct bicycles around a street car transit stop in the vicinity of a bike lane (see case study #13) and to provide bicycle access through an offset intersection (see case study #23).

Purpose

    Intersection markings cognizant of nonmotorized traffic create on-street travel facilities and separated space for bicyclists. They also serve to increase awareness and safe behaviors by both cyclists and motorists.

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Considerations

    • Where intersection markings are to be considered, the road or street should be evaluated to determine what markings are appropriate.
    • Provide adequate width if space is created for cyclists.
    • Provide appropriate signs.
    • Use marking and sign configurations that encourage the weaving of bicycles and motor vehicles where there are adequate gaps in traffic, usually in advance of the intersection proper.
    • Signalized intersections should be designed to detect bicycles.
    • Consider right-turn-on-red restrictions to reduce conflicts.

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Estimated Cost

Costs will vary due to the type of paint used and the size of the symbol, as well as whether the symbol is added at the same time as other road treatments.

Infrastructure
Description
Median
Average
Min. Low
Max. High
Cost Unit
# of Sources (Observations)
Pavement Marking Symbol
Pedestrian Crossing
$310
$360
$240
$1,240
Each
4(6)
Pavement Marking Symbol
Shared Lane/Bicycle Marking
$160
$180
$22
$600
Each
15(39)
Pavement Marking Symbol
School Crossing
$520
$470
$100
$1,150
Each
4(18)

Painting a bicycle box will cost approximately $11.50 per square foot. Striping combines a number of related costs, such as: contraflow lanes, broken/solid white or yellow stripe, bicycle lanes, and bikeway centerlines. It also combines the wide assortment of widths and materials used for striping.

Infrastructure
Description
Median
Average
Min. Low
Max. High
Cost Unit
# of Sources (Observations)
Pavement Marking
Advance Stop/Yield Line
$380
$320
$77
$570
Each
3(5)
Pavement Marking
Advance Stop/Yield Line
$10
$10
$4.46
$100
Square Foot
1(4)
Pavement Marking
Island Marking
$1.49
$1.94
$0.41
$11
Square Foot
1(4)
Pavement Marking
Painted Curb/Sidewalk
$1.21
$3.40
$0.44
$12
Square Foot
4(5)
Pavement Marking
Painted Curb/Sidewalk
$2.57
$3.06
$1.05
$10
Linear Foot
2(5)

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Case Studies

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