Vertical Elements: Vertical elements in the buffer are recommended. The same vertical separation used on the rest of the bikeway can generally be continued until the intersection.
Traversable Separation: In some cases, it is desirable to provide flush or traversable buffers to allow riders to exit the bike lane ahead of the intersection. If high bicycle volume or speeds are anticipated, or if turning drivers are expected to block the bikeway temporarily, it is desirable to provide people on bikes with points where they can exit the lane ahead of the intersection.
The combination of flexibility and separation from motor vehicles can be provided with a marked buffer with flexible delineator posts or other discontinuous, low-impact elements. To reduce interference with street sweeping or snow clearing operations, short raised elements, such as modular speed bumps, should be placed in line with curbs or higher raised elements, such as vertical delineators.
Curbs: Curbs or other hard elements that end at the crosswalk can prevent turning cars from encroaching on the bikeway before the intersection. If built curbs, medians or other continuous vertical elements are used in the buffer, the recommended minimum bikeway width is 6’.
Raised Bike Lanes: Often separated by a mountable curb but no other buffer, raised lanes can also use dedicated intersection geometry. The bike lane can slope down to the grade of the cross-street, or can remain slightly raised to encourage turning vehicles from the main street to yield.
Buffer Markings: Buffers less than 2’ wide can be marked as a double white line indicating that crossing is prohibited or a wide single white line indicating that crossing is discouraged. If wider than 2’, two pairs of parallel white lines should be marked. Optional color pavement treatments between the white lines contribute to the conspicuity of the buffer, add aesthetic value, and reinforce the walking-friendly nature of the space.
If the buffer is 4’ wide or wider, either color pavement or channelization chevrons should be used. If the bikeway buffer is 6’ or wider at the intersection, see Protected Intersections.
Crossbike / Bike Lane Line Extensions: Broken white lines with dashed green bars should be used across the intersection.
Signals: Using a combination of a leading bike signal phase or interval, and setting back the stop bar for motor vehicles, people on bikes get a head start before cars start turning. A Leading Bike + Pedestrian Interval (LBI) can be provided if a shared through/turn lane is next to the bikeway. If a dedicated right or left turn lane is next to the bikeway, protected-permissive bike signal phasing should be considered.25 Protected signal phases should be considered if turn volumes from the adjacent lane exceed 120 to 150 vph. Protected signal phases should also be considered if conflicting left turn volumes (on two-way streets) across the bikeway exceed 60 to 90 vph, or if these turns cross multiple traffic lanes.
Signs: A modified “Turning Vehicles Yield to Bikes and Pedestrians” sign (R10-15) is recommended at dedicated intersections.27 It is required in jurisdictions where pedestrians and bikes do not automatically have the right of way over turning vehicles. The sign should be mounted in accordance with existing location standards. (This modified sign is experimental under the 2009 MUTCD.)