1.6 Separate bikes at speeds over 20 mph

1.6 Separate bikes at speeds over 20 mph [Hector]

Bike lanes are a useful and necessary alternative to achieve a complete bike network in any city. However, on the wrong conditions, a bike lane can be a cyclist worst nightmare.

This category serves the purpose of systematic safety in speed control and separation. It is known that speed is not controlled by merely posting speed limits on a wide, straight rode. Roads need to be designed in order to obligate the driver to drive in a certain speed. This ensures safety for bikes also. However when cars go over 20 mph, bikes need to be separated from traffic

In the Netherlands, traffic and transportation engineers have found the optimal condition for bike lanes. First they should be on a 1+1 lane, meaning one lane roads on each side of traffic. This ensure that cars aren’t able to pass each other, assuring slower speeds. Another issue with bike lanes is the on street parking. On streets with parking and bike lanes, there is a chance of bikers getting doored. This can be  very dangerous situation since cars are riding in the street next to the bike lane. To answer this problem the dutch have found ways to accommodate on street parking in a way that does not endanger cyclist. The following sites show some of the strategies used by the dutch.

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  • Dorpskade, Watering
    • Same Layout  since 2008




The previous two pictures show how the street was laid out in order to make it safe for cyclist. It is a 1+1 road with a slightly raised bike lane and parking on both sides. It is important to note that this is still considered a bike lane since there are no physical barriers to classify it a s a cycle track. This road is located in a residential area. Therefore parking is critical. In order to keep parking and the bike lane; the dutch found a solution which was to raise the bike lane and the parking together. By doing this cars wont stop in the bike lane like they normally would on a leveled bike lane to make drop off or to pick up someone (Example shown below). Also there is a small elevation from the parking to the sidewalk. It is big enough for people to distinguish the sidewalk and small enough for cars to drive on it as shown in both pictures. This makes the 7.5 foot parking seem larger than it is. As seen on both pictures, bikes have little risk of getting hit by a parked car opening the door and also feel far from ongoing traffic on the left.




This video shows how traffic on the street behaves and how streets free the bike lane is for cyclist.

  • Emmastraat, Pijnacker
    • Same layout since 2010


  • Cars are parked vertically from the street making it safer for cyclist. There is no chance of being doored and the cars shown on the picture can clearly se if cyclist are coming. If a car parks with its rear towards the street there is still space in between the car and the bike lane in order to give the cyclist time to react if a car does not see it while baking up.


The picture above shows a one way residential street with a contraflow raised bike lane. This offers a vertical separation from the road and the bike lane. In order to keep a bike lane and have the needed on street parking, since it is a residential area, the bike lane and the parking was raised. This ensures that cars on ongoing traffic stay on their lane and don’t invade the bike lane. Also if there is an emergency or something obstructing the road, cars can go onto the bike lane and drive around whatever is blocking the street\.



  • Verlengde Groenstraat, Nijmegan
    • Same since layout since 2009


Verlengde Groenstraat is a two way residential road. It is classified as a fietsstraat therefore bikes have priority and vehicles are guests on the road. The road is wide enough that bikers dont worry about getting hit by parked cars opening their doors. Also the parking is raised art the same level as the sidewalk. It is also not a coincidence that the sidewalk and the parking look alike. If there are no cars parked on the street it serves as extra space for sidewalk.


There is also a permeable barrier in the street discouraging traffic from using this road a some type of shortcut. Therefore the cars that pass through this street are only people that live in or a  visiting a house in the street. The map below shows how this residential street could be used as a cut through route but since there is a permeable barrier on the street, the only traffic is cars that are coming and leaving homes.

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  • Spielmaskerstraat, Delfgauw

Before (2009):

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Picture above shows how the street was laid out in 2009. As of today there are bike lanes on both sides.

Current View



The two pictures shown above illustrate both sides of the residential area. Since it is a residential area, parking is very valuable. IN order to mix bike lanes and parking they decided to make the parking angled to the street. This bikes don’t have to worry about getting doored. However one might think that the danger know is greater since you could get run over by a car leaving the parking and not see you. To avoid this conflict they left a 2′-3′ buffer from the end of the bike lane to the parked car. In this scenario cars have a view of the bikes coming. Also if the driver does not pay attention and doesn’t see a incoming bike, the cyclist has time and space to react and maneuver his way to safety.


  • Oostlaan, Pijnacker:
    • same layout  since 2008



Comparing to the United States (Boston):

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The picture above shows Massachusetts Avenue. This is an interesting scenario since there is a bus stop at the start of the street in the right. There is also a bike lane going along the street. Below is a picture of how the dutch deal with bike lanes and bus stops. To minimize conflict points, the dutch pass the bike lane behind the bus stop making it safer for cyclist.

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The picture above in Commonwealth Avenue shows the response to the danger of having a bike lane on a two lane road with parking. Instead of changing the design of the street or raising the bike lane or building  a cycle track, Boston simply moved the lane to the left hand side of the street. Of course this is the cheapest and fastest solution. However it creates another problem. One pro of the bike lane being on the right hand side is being able to move ride to your destination and park your bike in the sidewalk. To do this with the bike lane on the left, one must criss two lanes of ongoing traffic to reach the sidewalk.

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The picture above is unique because a little back on Beacon Street they have made a seperated bike lane but when the street reaches this point it convert to a narrow bike lane. This is a fairly uncomfortable bike lane since there is traffic on the two lanes on your left and a on street parking close to your right. Following systematic safety and Dutch principles this would not be acceptable. on alternative that the dutch would use is raise the bike lane with the parking.

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The picture above shows the ideal conditions to replicate Emmastraat in Pijnacker (re-shown below). This street is Marlborough St. and it is a residential road coming out of Massachusetts Avenue. Like in Emmastraat there could be a contra flow bike lane which is raise with the parking. This way parking is not taken away and also a safe bike lane is added. This would make sense since this is already a residential streets and speeds should be slow. By adding the raised lane, the travel lane becomes narrower, forcing cars to go slower.