A Deeper Look into Advisory Bicycle Lanes

I’ve discussed advisory bike lanes in previous posts, but let’s come back and take another look at what they are trying to achieve and how.

Advisory bike lanes are used when there is too much traffic to mix bikes and cars comfortably in the travel lane, but not enough space to allow for both bidirectional travel lanes and bike lanes or cycle tracks. This is a standard Dutch treatment used only on roadways that do not have centerlines in both urban and rural settings for roads with an average daily traffic between 2000-5000 vehicles.

Advisory bike lanes are marked with a dashed white line that suggests that motor vehicles may enter the bicycle lane when they encounter an oncoming vehicle from the opposite direction. Motorists normally ride in the center of the travel lane, except when another motorist approaches and they shift slightly to the right after yielding to any bicycle traffic traveling the same direction. Advisory bike lanes are sometimes painted red, which reinforces that bicycles have priority in the space and that motorists must yield to bikes when entering that space. Sometimes they include bike symbols painted in the advisory lanes, but not always.

In the U.S. where advisory bike lanes are still considered experimental treatments, the common response or “solution” is to do nothing, or at the very least add sharrows (i.e., share the road arrows) or “share the road” signs. This is obviously not much of a solution because it encourages the mixing of motor vehicle and bike traffic on a street that is too busy for that to constitute a comfortable, safe bicycling facility.

Urban Setting

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Cars passing on Maasstraat, Amsterdam

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Maasstraat, Amsterdam

Maasstraat | Amsterdam (Urban Commerical)

Maasstraat is a somewhat busy commercial corridor (30km/h or 18 mph) within in the Rivierenbuurt district. Three- to four-story, mixed use residential buildings with bottom floor retail line the corridor. You can find speciality stores, restaurants, cafés, clothing stores, and small- to medium-size grocery stores. At the midpoint of Maasstraat, these residential buildings are setback further from the street to create a square, the Maasplein.

Red colored brick pavers and raised crosswalks are used to indicate to motorized traffic that people walking or biking have priority in the space. People of all ages and abilities were using these advisory bike lanes to either visit shops on Maasstraat or travel through neighborhood on their way elsewhere.

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School zone along Westplantsoen, Delft

Westplantsoen | Delft (Urban Residential)

Westplantsoen is a low-traffic street (30km/h or 18 mph) located within a residential neighborhood adjacent to Wilhelminapark. The street is lined on both sides with three-story residential buildings, street trees, bike parking, and ample on-street parking. A school zone calls for additional traffic calming including raised crosswalks, additional signage, and speed limit reductions. School children and their parents are able to comfortably navigate the street comfortably using these advisory lanes and crosswalks. The advisory lanes are painted red and include bicycle symbols to deliniate a space for bikes.

Rural Setting

The Dutch commonly use advisory bike lanes on minor rural roads with no centerlines and speed limits of 60 km/h (37 mph).

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Bicyclist POV as a car passes along Zuideindseweg, Delfgauw

Zuideindseweg | Delfgauw

Zuideindseweg is a very narrow, rural road built on top of a dike. This low-traffic street (60km/h or 37 mph) provides a north-south connection between Delfgauw and Oude Leede. A small canal and expanses of agricultural land provide a picturesque view for those passing through. On average, it is about 4.5m in width (14-15 ft). Because it is built upon a dike, there is no room to widen it. Still, the Dutch allow for two-way travel for bikes and cars through the use of advisory lanes. In the U.S., this roadway width would only be sufficient for one-way travel lane (10ft) and a standard bike lane (4ft) without a buffer. This facility is comfortable to ride on as a bicyclist because cars occasionally pass, but it is not often that two oncoming motorists must navigate into the bicyclists’ lane while a bicyclist is there. While these advisory lanes are not painted red, it is still understood that bicyclists have priority to this space.

Potential U.S. Applications

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View looking south at NE 7th Ave and NE Graham St roundabout (Source: Google Street View)

NE 7th Ave, North of Broadway to N Going St | Portland, Oregon

NE 7th Ave north of Broadway is a residential street that is spotted with several small businesses and is anchored by Irving Park. Local residents have already petitioned the City of Portland to convert this into a neighborhood greenway (i.e., bike boulevard) and reduce the speed limit to 20 mph. The street already has some traffic calming elements including speed humps and small roundabouts at intersections with minor residential streets. Because support exists to implement further traffic calming, advisory bike lanes would be a good alternative for this low- to moderate-volume urban residential street.

NE 7th Ave is 35 ft wide curb-to-curb, which would leave room for 7 ft on-street parking on both sides, a 13 ft shared travel lane, and 4 ft advisory bike lanes. The existing roundabouts would continue to create pinch points along the route where cars must yield to bicyclists traveling the same direction in order to navigate the roundabout. Bicyclists already use 7th as a north-south connection, although it does not carry a designation within the city’s bike network. There is not enough room to accommodate standard bike lanes with the existing two travel lanes and there is just enough traffic that it is sometimes uncomfortable to share the roadway. This would be a low-cost treatment that would not sacrifice the existing sidewalks or on-street parking.

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Dekum St is designated as a shared roadway on the NE Portland Bike/Walk Map

NE Dekum St from MLK to 17th | Portland, Oregon

From Martin Luther King Boulevard to NE 17th Ave, NE Dekum Street is categorized as a shared roadway with moderate traffic in Portland’s bike network and has a 30 mph speed limit. The segment is primarily residential, but also includes a small business district adjacent to Woodlawn Park and is a couple of blocks from Woodlawn School (PK-8).  The segment is served by the #8 and #75 buses and is crossed by Durham Ave. neighborhood greenway.

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NE Dekum St looking east towards the small business corridor (Source: Google Street View)

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NE Dekum St looking west towards the small business corridor and five-way intersection (Source: Google Street View)

This small urban commerical corridor would be ideal for advisory lanes with an average daily traffic (ADT) of about 2,600 vehicles/day. Because it serves a small commerical district and a nearby PK-8 school, it is important to make it both comfortable, accessible, and safety for cyclists of all abilities to reach. The moderate traffic volume currently makes sharing the roadway uncomfortable and a weak link in the bike network. Advisory bike lanes would give space and priority to bikes that is needed along this segment.

A five-way intersection (NE Dekum St./NE Durham Ave./NE Oneonta St.) creates a point of conflict along the segment where dashed bike lanes (no symbols or paint) lead bicyclists through the intersection. In this case, advisory lanes with red paint and bike symbols would make it more clear who should be here and who has priority through the intersection. Increasing this clarity would likely increase the comfort and safety for all users.

 

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