Ayres Knowledge Center Using Bike Boxes to Increase Visibility and Safety | Page 7

DESIGN AND SIGNAGE
Bike boxes typically are installed only where bike lanes
exist. Leading up to the bike box is a marked ingress
area that connects the bike lane to the bike box, leading
bicyclists visually into the bike box. This marked bicycle
approach area typically ranges in length from 25 to 50 feet.
The NACTO Bikeway Design Guide calls for 10- to 16-foot-
deep bike boxes. The Austin report garnered feedback from
the public indicating an 8-foot depth was insufficient for
bikes to maneuver within the box. The width of a bike box
extends across some or all of the vehicular approach lanes.
“Further, public feedback has suggested extending the
bicycle box across multiple lanes to accommodate left-
turning bicy clists,” the Austin report states. “Although the
sites observed in this study did not have high volumes of
left-turning bicyclists, other intersections in the city often
do, so additional research into extending the bicycle box
into the left-turn lane would have merit.”
Bike boxes at North Avenue and 68th Street in Wauwatosa,
designed by Ayres Associates and installed in 2014, do
accommodate all bike movements, including left turns.
Bicyclists are able to position themselves ahead of the
vehicular left-turn lane, in front of the vehicular through
lane, or in the bike lane for either a right turn or a through
movement.
The bicycle symbol is placed in the center of the bike
box area to alert motorists and bicyclists that the area is
reserved for use by bicyclists. Multiple bike symbols could
be placed in the bike box, each showing bicyclists the ideal
spot to wait to command the left-turn, straight-through, or
right-turn lane; such bicycle symbol placement also might
indicate the optimal spot to wait to trip the system that
prompts the traffic signal to cycle to green.
A stop line is placed behind the bike box to indicate
the point behind which vehicles are required to stop
in compliance with a red traffic signal. In some cases
a message such as “Wait Here” is also painted on the
pavement behind the stop bar to reiterate to motorists
where they should queue when the traffic signal is red.
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