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Regional Boards => International Highways => Topic started by: cpzilliacus on April 15, 2013, 09:55:39 AM

Title: Cambodia: Development and Its Discontent
Post by: cpzilliacus on April 15, 2013, 09:55:39 AM
N.Y. Times:  Development and Its Discontent (http://latitude.blogs.nytimes.com/2013/04/12/development-and-its-discontent/)

QuotePHNOM PENH – In 2010, the Cambodian government unveiled with great fanfare the country's first traffic overpass. The $6 million project – lit with a futuristic blue neon swoosh – was intended to ease congestion where a major boulevard that runs north-south through Phnom Penh intersects with twin bridges that cross the Bassac River, just to the east. Prime Minister Hun Sen called the Sky Bridge Project a "great achievement"  and proclaimed that it would end traffic problems in the area.

QuoteIt wasn't long before commuters discovered a catch: By making it easier for motorists traveling north-south to keep going straight, the new overpass made it impossible for them to turn left onto the intersecting east-west road. The result is a mess. Now, drivers heading south who want to cross the river must first take a right and drive away for several hundred meters and then make a U-turn and head back. And motorists heading north are forced to turn right, which necessarily takes them onto the bridges – meaning that they are forced to cross the river, turn around and cross the river again. Congestion in the area is worse than ever, and the traffic more dangerous.
Title: Re: Cambodia: Development and Its Discontent
Post by: vdeane on April 15, 2013, 11:19:15 AM
Sounds like people aren't used to the concept of "limited access".  Though if I found the right spot, that interchange is poorly designed.
Title: Re: Cambodia: Development and Its Discontent
Post by: NE2 on April 15, 2013, 12:50:05 PM
This? http://maps.google.com/maps?ll=11.530486,104.930694&spn=0.002397,0.004128&gl=us&t=k&z=19
Looks like a typical third-world interchange - right turn ramps with U-turns to turn left. Mexico is full of them.
Title: Re: Cambodia: Development and Its Discontent
Post by: cpzilliacus on April 15, 2013, 08:46:26 PM
Quote from: vdeane on April 15, 2013, 11:19:15 AM
Sounds like people aren't used to the concept of "limited access".  Though if I found the right spot, that interchange is poorly designed.

Maybe like this (https://maps.google.com/maps?q=north+carlin+springs+road+%26+north+george+mason+drive,+arlington+county,+va&ll=38.874346,-77.116524&spn=0.004669,0.009645&safe=off&hnear=N+Carlin+Springs+Rd+%26+N+George+Mason+Dr,+Arlington,+Virginia+22203&gl=us&t=h&z=17) interchange in Arlington County, Va.?
Title: Re: Cambodia: Development and Its Discontent
Post by: NE2 on April 15, 2013, 09:08:19 PM
Quote from: cpzilliacus on April 15, 2013, 08:46:26 PM
Quote from: vdeane on April 15, 2013, 11:19:15 AM
Sounds like people aren't used to the concept of "limited access".  Though if I found the right spot, that interchange is poorly designed.

Maybe like this (https://maps.google.com/maps?q=north+carlin+springs+road+%26+north+george+mason+drive,+arlington+county,+va&ll=38.874346,-77.116524&spn=0.004669,0.009645&safe=off&hnear=N+Carlin+Springs+Rd+%26+N+George+Mason+Dr,+Arlington,+Virginia+22203&gl=us&t=h&z=17) interchange in Arlington County, Va.?
Not really. That one's missing two movements, both of which can be easily made with Park Drive.
Title: Re: Cambodia: Development and Its Discontent
Post by: kphoger on April 15, 2013, 09:31:13 PM
Quote from: NE2 on April 15, 2013, 12:50:05 PM
This? http://maps.google.com/maps?ll=11.530486,104.930694&spn=0.002397,0.004128&gl=us&t=k&z=19
Looks like a typical third-world interchange - right turn ramps with U-turns to turn left. Mexico is full of them.

But most of the ones I've encountered in México are where there is little left-turning traffic.  The article makes it sound like there is substantial left-turning traffic at the intersection in question; and, looking at the map, it's easy to see why.  I agree that this was not well planned.  A roundabout interchange (bridge over roundabout) might have been better bang for the buck.
Title: Re: Cambodia: Development and Its Discontent
Post by: NE2 on April 15, 2013, 10:35:50 PM
One at a major junction in Tijuana: http://maps.google.com/maps?ll=32.538483,-116.903533&spn=0.008249,0.016512&t=k&z=17
Another one where you U-turn at a roundabout: http://maps.google.com/maps?ll=32.526168,-117.015622&spn=0.004125,0.008256&t=k&z=18
Title: Re: Cambodia: Development and Its Discontent
Post by: kphoger on April 15, 2013, 10:41:28 PM
Quote from: NE2 on April 15, 2013, 10:35:50 PM
One at a major junction in Tijuana: http://maps.google.com/maps?ll=32.538483,-116.903533&spn=0.008249,0.016512&t=k&z=17
Another one where you U-turn at a roundabout: http://maps.google.com/maps?ll=32.526168,-117.015622&spn=0.004125,0.008256&t=k&z=18

Yes, there are a few.  And, in fact, Tijuana specifically came to mind.  But it isn't the norm across the country for high-volume left-turning movements (and I'm not too convinced that the two you show have incredibly high volumes of left-turning traffic at the missing movements).  And I struggle to think of a single one at what could be considered one of the most crowded junctions in the whole city.