Dutch Bike Signals

[Chris]

Cyclist tunnels in the Netherlands generally have a 15 ft wide roadway plus a sidewalk, making the entire tunnel 20 - 25 feet wide easily. They are usually also well-lit and have long ramps.

examples;

[realjd]

Americans are afraid of pedestrian and bike tunnels in my experience. People will often call them "rape tunnels". They almost ripped out the new one in Viera, FL near the high school to allow students to cross the busy street because parents thought it would attract kidnappers. Talk about poor risk assessment. They're more worried about their teenagers being kidnapped in the short tunnel right in front of the school than they are about them getting hit by a car crossing the street.

[Chris]

Social safety in tunnels is a major issue in the Netherlands as well. It all begins with the proper design; you need to be able to look through the entire tunnel from the beginning, the tunnel section must not be too long, nor in a long curve (my first one is a bad example), well-lit and also the cladding must be bright. It helps if the police does occasional surveillance as well, I often see motorcycle cops driving through cyclist tunnels at night.

[Duke87]

If a tunnel is too much of a hideout for sketchy characters, how about a bridge instead?

[NE2]

Bridges are known to be home to trolls. (They're also less convenient, since you go up then down; in a tunnel you get the speed boost first. And they need to be higher than a tunnel is low to clear trucks.)

[Zmapper]

One of the small things I noticed when I was looking around the Netherlands with Google Streetview is that if a road goes into a tunnel and there is a cycle path next to it, the cycle path doesn't make such a vertical change. So if the road needs 16' of clearance and the cycle path needs 10', the road goes down 16' feet and the path only makes a vertical change of 10'. Make sense?

[NE2]

I've seen this on some older railroad grade separations in the US - the sidewalk will not go down as much as the road. Here's one in Jacksonville where the sidewalk stays with the road but an old streetcar route in the middle is higher: http://maps.google.com/maps?ll=30.329356,-81.676628&spn=0.00401,0.0103&z=18&layer=c&cbll=30.329455,-81.676608&panoid=dJGttQPFrFM1bW-yajWwNQ&cbp=12,172.48,,0,-5.44

[mightyace]

^^^

Me, too.  Here's one where the sidewalk is higher than the roadway.

US 11 going under Norfolk Southern (ex-PRR) in Norhtumberland, PA
http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=Northumberland,+PA&aq=0&sll=30.329453,-81.676607&sspn=0.002144,0.004823&ie=UTF8&hq=&hnear=Northumberland,+Pennsylvania&ll=40.886005,-76.795635&spn=0.030044,0.077162&z=14&layer=c&cbll=40.886101,-76.795568&panoid=fDgULJLr_9KgDRUSJDpTJg&cbp=12,36.54,,0,-2.2

[Chris]

One of the small things I noticed when I was looking around the Netherlands with Google Streetview is that if a road goes into a tunnel and there is a cycle path next to it, the cycle path doesn't make such a vertical change. So if the road needs 16' of clearance and the cycle path needs 10', the road goes down 16' feet and the path only makes a vertical change of 10'. Make sense?

Yep!


N36-25 by Chriszwolle, on Flickr

[roadfro]

^ That seems kinda odd to me. Ultimately, though, I imagine it helps to maintain the vehicle/bicycle separation. It also means possibly means less earthwork during construction (but also more in retaining walls). Any particular reason why the paths are constructed this way?

[Scott5114]

Also less effort for bicyclists to go up a hill on the way out.

[froggie]

I imagine it's two-part....vehicles (especially small trucks) need more clearance, and as Scott indicated, bicyclists are more sensitive to grade changes.

[Chris]

Yep, the main reason is that cyclists will need less effort to scale the grades in these tunnels. It's more comfortable. There are guidelines in the Netherlands about how long a cyclist ramp may be and what grades it should have. If it's too long, they need to include a flat section before the second climb commences, though you won't find that many of those. Keep in mind there are also numerous young children and senior citizens using a bicycle in the Netherlands, that's why you cannot just design such things for fit adults only.

Here's an example of such a grade broken into two sections:

N302-5 by Chriszwolle, on Flickr

[Dr Frankenstein]

Another example of grade separation between car lanes and bike/ped paths in a tunnel. http://maps.google.ca/?ie=UTF8&ll=45.315068,-73.918483&spn=0.008495,0.016351&z=16&layer=c&cbll=45.315041,-73.918593&panoid=_yOD6lUwsbokUdDgFK7D2A&cbp=12,267.93,,0,16.18