Types of Bicycle Infrastructure

Bike Path

A bike path is a paved pathway separated from motorized vehicular traffic by an open space or barrier and either within the highway rights-of-way or within an independent alignment. Bike paths may be used by bicyclists, skaters, wheelchair users, joggers, and other non-motorized users. In the case that there is no pedestrian facility adjacent a bike path, the bike path may also serve pedestrians. Caltrans refers to this facility as a Class I Bikeway which “Provides a completely separated right of way for the exclusive use of bicycles and pedestrians with crossflow of motorists minimized.”

Cycle Track (or Protected Bikeway)

A cycle track, or protected bikeway, is an exclusive facility for bicycles that has the protection features of a separate path, but is located on a street.

Buffered Bike Lane

A buffered bike lane is a bike lane paired with a painted buffer, which directs people driving cars to travel away from the bike lane and provides room for people riding bicycles to pass another person on a bicycle without entering the adjacent motor vehicle travel lane.

Bike Lane

A bike lane is a striped lane for one-way bicycle travel on a street or highway. Caltrans refers to this facility as a Class II bikeway.

Sharrowed Route

A sharrowed route is a roadway where people riding bicycles and driving cars share the same space with no striped bike lane. Although sharrowed routes are usually demarcated by “sharrows,” or a bicycle and painted arrows on the roadway, in conjunction with the “Bikes May Use Full Lane” sign, any roadway where bicycles are not prohibited by law (i.e. interstate highways or freeways) is a shared roadway. Sharrows are the most practical solution to close gaps between existing bikeways on streets that cannot easily accommodate bike lanes.

Neighborhood Enhanced Street

The Neighborhood Enhanced Street is a roadway that provides comfortable and safe localized travel for slower-moving modes such as walking, bicycling, or other slow speed motorized means of travel. Enhancements can take shape in the form of a variety of traffic calming features depending on local context need or may not be required if street meets targeted speeds and volumes.

Neighborhood Enhanced Street

Signage

Signage is used to direct people on bicycles along preferred routes, to reach nearby destinations, or to provide some sort of warning. Signs are a cost effective, yet highly visible, and therefore are an important part of any complete bicycle network. The application of signage itself does not radically alter the physical characteristics of a street, but signs are subject to standards set forth by the California Manual on Uniform Traffic Control Devices (CA MUTCD), which regulates everything from sign shape and color to size and positioning. Determining the placement and extent of signage application requires network analysis, engineering, and design work, but gathering community input is also important for wayfinding projects.

Wayfinding Signs

Wayfinding signs help people walking and bicycling get to their desired destinations. The City utilizes wayfinding signs that display both destinations and distances, allowing people to optimize their route selection. Wayfinding signs also offer reassurance to people walking and bicycling that they are going in the right direction. Signs are strategically placed at key locations both leading to and along corridors with bicycle infrastructure. Ideal locations for wayfinding sign placement include bicycle network intersections and other key decision points.

A citywide bicycle wayfinding project, funded by Metro, is anticipated to begin installation in 2017.

Bicycle Box

Bicycle boxes are a treatment applied at signalized intersections, typically in conjunction with restricted right turns for motor vehicles. This treatment resets the automobile limit line, requiring people driving to stop at a red light a few feet before the crosswalk. This allows people on bicycles to position themselves in the front of the queue and be first to move through the intersection when the light turns green. Bicycle boxes are typically 14 feet wide to provide people on bicycles enough space for proper positioning. On two-lane roadways, bicycle boxes can also help facilitate left turn movements for people bicycling by making it easier to position themselves appropriately and ensuring they are visible when signaling a left turn.

The primary benefit of a bicycle box is that it provides a designated space for people bicycling when stopped at an intersection. This reduces conflict between bicycles and automobiles because it makes clear where people on bicycles should stop during a red light while also increasing the visibility of people on bicycles, who can often be visually obscured at intersections. Without bicycle boxes, it can be unclear where people on bicycles should be, especially for those unfamiliar with bicycling.

Stay tuned for a pilot installation of bicycle boxes in the City of Los Angeles.

Loop Detectors

The majority of signalized intersections in Los Angeles are controlled and monitored by a centralized control center called ATSAC (Automated Traffic Surveillance and Control). ATSAC provides real-time monitoring and adjustment of signal timing via over 20,000 loop detectors across the city.

Loop detectors are coils of wire set into the pavement which, after they are electromagnetically triggered by metal, alert traffic signals to change in the direction one is traveling. At certain intersections in Los Angeles, the only way to get a green light is to properly position a vehicle, car or bicycle, upon a loop detector. This is performed effortlessly in an automobile due to the vehicle’s size. However, due to the small size of a bicycle, loop detectors cannot detect the presence of the vehicle without correct placement on specific sections of the loop.  Unfortunately, this is not well-known among the wide range of people who use bikes.

One way to address this issue on bicycle-friendly streets is to place bicycle stencils on the portion of the loop detector where bicyclists should be positioned in order to be detected at a signal. These “bicycle-friendly loop detectors” communicate the ideal positioning for bicyclists sitting at red lights.

Changing Lights with Loops

Notably, it is not the weight of the bicycle that triggers the loop detector, it is the metal in the bicycle interacting with the electricity running through the loop detector. This means that carbon-fiber bicycles with carbon wheels may not have enough metal to set off loop detectors.

There are a variety of different loop detectors, and some are easier for people riding bicycles to use than others. There are “Circular Loops”, “Square Loops”, “Q Loops”, and “D Loops.” See the diagram below to find the optimal placement for each type of loop.

As of 2007, California state law (with the passage of AB 1581) requires all new loop detectors to be sensitive enough to detect bicycles. Bicycle detection at intersections is also now part of the CA MUTCD (Manual on Uniform Traffic Control Devices) , contained in Part 4 (pages 67-68 & 88-90) and Part 9 (pages 32 & 44).

The City of Los Angeles currently uses circular loop detectors, the one in the top left of the graphic.  The best place to put your bicycle at an intersection is directly over the right or left edge of the loop.  Because circular loops are the least effective at picking up bicycles, the LADOT Traffic Signal Design Guidelines also call for a diagonal strip to be put through all loop detectors adjacent to the “limit line” (the edge of the intersection) in order to better detect bicycles.

The City of Los Angeles also has loop detectors specifically built for bicycles. These are typically installed on bike lanes and resemble a smaller version of the “Square Loop” shown above.

Report Bad or Faulty Loops

If you come across any nonfunctioning loop detectors, please report them to LADOT and we will fix or adjust them as necessary. The length of time between signal changes once a loop detector is activated can greatly vary by intersection, so please be extra certain the loop in question is not functioning before reporting it. The proper place to report a non-functioning loop detector is with your LADOT District Office.

Diverters

When drivers treat Neighborhood Streets as a bypass to nearby busy arterial streets, they create dangerous road conditions and an unpleasant living experience for local residents. A traffic diverter’s purpose is to direct non-local vehicle traffic away from Neighborhood Streets using vertical deflection. The treatment deflects and discourages cut-through car traffic, but preserves an attractive route for people using non-motorized modes of transportation like walking, bicycling, or skateboarding.

When successfully implemented, local residents benefit from the safety, noise, and other quality of life factors that result from the elimination of cut-through traffic.  Those attempting to bypass busy arterial streets are no longer enticed to take this “shortcut.”  Traffic Diverters use street design to put car traffic back where it belongs while providing a calm, safe, and enjoyable neighborhood environment for people on bicycles, walking, children, and pets.

Diagonal Diverters

Diagonal diverters are meant for the intersection of two local streets. Since local streets are not designed for nor have the capacity for through traffic, a diverter will encourage non-local drivers to avoid these streets. Typically, a diagonal diverter will have a wide-paved center which blocks through-traffic with a flexible or removable bollard or curbing.  This street design element can be designed to allow emergency vehicles to pass through when necessary.

Raised Median/Crossing Island

While a diagonal diverter is only appropriate for smaller residential streets, installing raised medians or crossing islands can improve a Neighborhood Street where it meets with a larger arterial street.

As shown in the photo above, a raised median/crossing island allows through traffic for bicycles along a Neighborhood Street while directing drivers onto an arterial street more appropriate for heavy car traffic. While a diagonal diverter redirects traffic in all directions, a raised median only redirects traffic from the Neighborhood Street.

Raised medians and crossing islands also make the crossing of larger arterial streets much easier and safer for people bicycling and walking. By providing a protected space between directions of traffic, people walking and bicycling can cross a street one direction of traffic at a time by safely pausing in a protected median space.