HW4 Delft Alex Bender

Overview

Before coming to the Netherlands, I studied up on Dutch bicycle infrastructure both independently and through our pre-departure assignments. I was sure that through those brief overviews I had a true grasp of many of the differences between the Dutch and the Americans. I was confident that I understood. Boy was I wrong! Seeing truly is believing, and it sure is a sight to see. There are bicycles everywhere! People treat cycling as a irreplaceable form of transportation, not as a hobby. In our rides, I observed people of all ages riding bicycles. The infrastructure here is conducive to high access and high utilization.

We had the opportunity to experience six different types of biking facilities: Bike lanes, advisory lanes, cycle tracks, bike boulevards, service roads, and bike highways. These six types are able to transport large masses over various distances. They all have certain criteria that make them successful, and they all are designed in a way to maximize safety. In general, successful cycling infrastructure must be coherent, safe, direct, comfortable, and attractive. Below, I will outline the six facility types by detailing examples of each.

Bike lanes

Creating a bike lane involves painting a lane line to designate an area for bikes to ride. The lane is typically on the right side of the road between intersections. Because this can be implemented without a lot of construction, bike lanes can be a cheap bike facility to offer. Some bike lanes can be low stress; ample buffer space is needed to make the rider feel as though they have a defensible space. Some dangers of bike lanes involve the lack of vertical protection between moving cars and bicycles and being “doored” (hit by a parked car’s open door). According to standards manuals bike lanes should be a minimum of four feet wide, yet special boundary conditions (environmental factors on the boundaries of the bike lanes) can cause that to increase or decrease. Bike lanes are typically predictable and simple because everyone recognizes red painted pavement as an area for bicycles.

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Above we see a 7 foot wide bike lane on a 1+1 road (1 lane per direction). The road is a access road with many intersections and driveways; it suits to serve mainly residential and commercial areas. Since the road is 1+1, cars cannot pass each other, and, therefore, they cannot speed if there is another car in front of them. This, along with the wide median, help to make the road simpler and more predictable. Typically, designer want at least a five foot bike lane, but when it is next to a row of parking, the desirable width becomes about seven feet. Ideally, there will be a 14.5 foot reach between the curb and the left side of the bike lane. In the above example in Buitenhofdreef, there is a total reach of just about 14.5 feet, so this is a good example of a bike lane providing riders ample buffer from being “doored”.

While riding on this strip, I felt very safe as I think most riders would. The narrow travel lane and the wide reach ensured a comfortable ride.

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Above is an example of a cycling situation in which I felt the least safe that I have in my time riding in the Netherlands. While riding on Martinus Nijhofflaan, there is a stretch that has a construction wall protruding into the bike lane. This causes the bike lane to be a meager 3 feet during this section. This is below all minimum bike lane widths. Out of curiosity, I tracked back 1 year via google maps to see how temporary this wall was, and I discovered that it has been there for at least a year. This can be a safety risk for cyclists.

Martinus Nijhofflaan is an access road that suits to serve commercial areas and to distribute traffic to local and other access roads. It sports a fairly wide 11.5 foot lane in this section. The width of this lane causes the phenomenon of risk compensation. This means that drivers’ behavior changes to make them drive less carefully, up until a manageable amount of risk. The wide lane causes drivers to think they can take up that whole space which then sandwiches cyclists in a very tight space. In this situation, you would want at least a 5 foot bike lane, in order to compensate the standard 4 feet plus an added foot for a shoulder level wall boundary condition.

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Above on Nassaulaan, another access road serving commercial, residential, and educational areas, we see a 5.8 foot bike lane next to row parking. This is not an ideal reach, but it is sufficient. There is risk of being doored, yet this lane will still enable a rider to avoid that conflict.

In general, bike lanes are going extinct. There isn’t much motivation to build them anymore. Also, it is now frowned upon to have bike lanes on 1 + 1 road with parking, since that fear of being doored always adds some discomfort to a cyclist.

Here we see the bike lane ends when it reaches a narrow school zone. In this area cars must yield to passing bicycles; the change in pavement color, texture, and width sends a message to drivers to slow down. The changes in pavement are self enforcing speed control, which then enables bicycles to mix with cars for this brief stretch.

Overall, I felt safe riding on this road. The parking seemed very low turnover and cars did seem to actually go slowly.

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Similar to Nassaulaan, Julianalaan serves a similar population. Here we see the Dutch “skinny roads, wide nodes” philosophy. Dutch infrastructure favors skinny lanes between intersections and wide intersections to control speed and maximize throughput.

This bike lane is a sufficient width, but it is not ideal. The reach is not quite 14.5 feet, and there exists no 3 foot shoulder level buffer needed for a car door. While riding between the two cars pictured, I did feel some discomfort. A wider reach could have helped to curb this anxiety.

In the right picture, we see a potential conflict zone. This is when bicycles that want to turn left have to cross a 10 foot travel lane to do so. We also see a pocket bike lane—pocketed between a through lane and a right turn lane. The right turn lane pictured is not designed well. Since it does not begin close to the intersection, and the turn angle is not greater than 80 degrees, cars can and do zoom by to make their right turns. This presents an anxiety inducing situation to cyclists when there are two zooming cars on both side of you while in a 5 foot though bike lane.

Advisory lanes

Advisory lanes exist on unlaned roads with an average daily traffic(ADT) of 2000-5000. They are also referred to as suggestion lanes. The dashed lines and sometimes painted stripe details suggested bike lanes, however cars must sometimes cross into them. They use this space when there is opposing traffic. The central zone of an advisory lane can vary widely in width.

These are a great way to give bikers a defensible space, while still giving two way traffic ample passing room. They work well on narrow, low volume local roads when long queues of cars do not form.

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Above we see the local roads Hugo de Grootstraat, Adriaan Pauwstraat, Westplantsoen, and Westplantsoen 212. They all serve a similar purpose of serving this residential area of Delft. The central zones of these advisory lanes are 13 feet, 10.3 feet, 9.2 feet, and 6 feet respectively, which makes it so two passing cars must negotiate with one another and utilize advisory lane space to get by. As you can see, the central zone widths can vary widely(and even be as narrow as 6 feet!).

It is apparent that advisory lanes make for a great retrofit design project along historic, local roads. When volume, speed, and pavement width is low(often on historic, local roads), an advisory lane is a surefire way to safely convey cyclists and motorists alike.

Similar to a bike lane, passing by a row of parked cars can cause discomfort, but advisory lanes tend to be safe and comfortable(my experience was very pleasant). The speeds and volumes are usually very low.

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Finally, we see another, more rural example of an advisory lane in Delfgauw. This road brings cars from a very rural part of the “Green Heart” to the suburbs/outskirts of Delft. With the long and straight rural road becoming a local road, they needed to control speed. This road was retrofitted for speed control by visually making the central zone very narrow(7.8 feet), and adding a tree barrier that causes vehicles to slow down to 30 km/h and maneuver around it. As you can see, this advisory lane solution gives enough space for multiple cars, bikes, and even very wide vehicles such as the truck shown above.

Cycle tracks

Cycle tracks offer a protected bike lane for cyclists. The tracks must be separated from moving car traffic by either some form of vertical separation(greater than 4 inches), or an unpaved area of reasonable length. They can be one way and two way. Generally, 1 two way cycle track takes less space than a pair of one way cycle tracks. Two way cycle tracks can be dangerous at intersections, but this risk is mitigated with raised crossings and protected turns(via a traffic signal).

Cycle tracks can be at street level, sidewalk level, or an intermediate level in between the two. The separation from pedestrians must be more than just a patch of rough pavement because in general pedestrians do not mind walking on that surface. Light posts and other incremental vertical separation do a good job at separating cycle traffic and pedestrian traffic.

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The cheapest way of implementing a cycle track is by adding a two foot painted buffer on the right side of a row of parked cars. Above on Papsouwselaan, they go above and beyond the minimum conditions for a protected cycle track. The 2 way cycle track length on this stretch of road is 10 feet, as noted above. The minimum space needed for a two way cycle track, after sufficient buffer is ensured, is 8 feet. This extra space and buffer help to make cyclists feel very comfortable; I can vouch for this experience, as a user.

Historically, Papsouwselaan was a 2 + 2 road that lacked functional harmony. It carried a lot of through traffic, local/access traffic, buses, and trams. This stretch of road underwent a stark road diet, which helped to enable cyclist by feeling more comfortable (with the extra space) and traffic to be more controlled(making a 1 + 1 road with median and without traffic light). The new design is very space efficient, even making the central zone a shared space for buses and trams.

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On hard to cross roads, people will ride two way anyway, so it makes sense to equip both sides of the road with a two way cycle track, as was done on Voorhofdreef. The two way cycle track gives cyclists more of a path feeling, and the vertical separation from cars(via curbs and trees) helps to protect the cyclist. This cycle track offered a very smooth and safe ride. Another factor that helps to make cyclists feel more comfortable is the fact that they have priority on intersection, as shown above. Vehicles must wait in a yielding bay. The separation from pedestrians also mitigates any feeling of discomfort for a cyclist. The 10 foot wide cycle track provides a very pleasant amount of room.

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Ruys de Beerenbrouckstraat turned out to be such an interesting road to study. This area recently underwent a large road diet that enabled this road to carry through traffic, while not endangering the residents trying to cross. They did this through robust speed control and cutting it down to 1 + 1 with a small roughly paved median.

Ruys de Beerenbrouckstraat also sports a pair of one way cycle tracks on both sides of the road. In general, designers must consider transition at endpoints and the complexity/safety at intersections. As you can see above, safety at intersections was a huge priority. The wide one way cycle track crosses the intersection with priority. Cars entering must ride up onto a crossing table and yield at the “shark’s teeth” yielding symbols. This crossing table grabs the attention of drivers, forces them to enter the bikers’ zone, and sows them down in general.

Cyclists feel safe on this cycle track, largely due to width, safety at intersections, and the vertical protection from moving cars, as detailed above.

Regarding crossing this street as a pedestrian, drivers recognize the red brick to delineate an especially cautious, slow zone. This invokes the third principle of systematic safety: predictability and simplicity.

Bike Boulevards

Bicycle Boulevards, also known as Quietways, offer cyclists a nice through route following calm, local streets. In order to classify as a bike boulevard, the route must have meaningful length and serve through bike traffic without serving through motor traffic. This can often be done with the utilization of permeable barriers(barriers that allow cyclists to pass through, but not cars).

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The above example on the Abtswoude path, shows the attention that cyclists receive here in the Netherlands. A large move-able bridge over a shipping canal was built just to transport cyclists and pedestrians. I fear that this is very rare in the United States. This example follow calm, local streets with robust motor speed control. This makes for an extremely comfortable ride because cyclists are often going just as fast as cars, and traffic volume is typically low. The Abtswoude path serves through bike traffic, but not motor traffic, as shown by the move-able bridge.

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The bicycle boulevard along Buitenwatersloot features a permeable barrier and bus sluice. This enables through line bus and bike traffic but not normal car traffic. This car dead end is enforced by a camera that will take pictures of violators and mail them a fine. This long quietway used to be a historic through traffic road, but the municipality decided to demote it once a large bypass was constructed. This conversion from a historic road proves the prioritization of bicycles. Finally, along parts of the road there is slow, one way car traffic, but the city allows for contraflow bicycle traffic to enable people to cycle in both directions. Often times when a route is convenient, cyclists will do contraflow anyway, so it is logical to permit it by law. As Furth says, “There is no life without contraflow!”

Service Road

Service roads enable cyclists to ride in a very low stress environment parallel to a main, through traffic road. These are successful when the speeds and traffic volume are low. This is a great way to save space because you can utilize already existing local road, implement robust speed control, and disallow motor through traffic through the use of permeable barriers.

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Here on Zuidpoldersingel, there is a vertical bollard that acts as a permeable barrier for bicycle, disallowing car traffic. This maximizes functional harmony by keeping the main road as a through road and keeping the local road as a local road. Cycling along this service road was very comfortable and stress free. Parking was very low turnover and all cars traveled very slowly.

Bike Highway

Bicycle highways offer a stand-alone path used for only cycling traffic. Though it can be expensive, it offers a very fast, direct route for cyclists. The environment is typically low stress because there is zero car traffic stress.

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Above we see a bicycle highways located in Delfgauw. This route offers a very wide, continuous path for cyclists. There are very few conflict areas, so cyclists do not have to worry about much. This route was very low stress and very enjoyable.

As the bike highway approaches an intersection, the infrastructure designers ensured that all conflicting parties were aware of the upcoming conflict zone. According to the first principle of systematic safety(speed control and separation), it is imperative to limit speed in potential areas of conflict. For the cars, speed is limited by an s-curve and a compulsory STOP sign. For cyclists, speed is controlled by two concurrent depressions in the path of the cycle highway. Cyclists have priority at this intersection, but it is important to make sure cars respect that while still ensure cyclists are being aware and not just flying through the conflict zone. Overall, the bike highway was very effective at conveying fast moving cycle traffic while maximizing safety in conflict areas.