I think you'll find this article interesting:
http://gizmodo.com/how-a-former-video-game-designer-created-the-best-inter-1707758013
Something tells me this topic could bring out some strong opinions :-D
Isn't this already a thing in Europe?
Edit: I remember watching the video in the article, but I feel like I've seen it somewhere else too.
Part of the difference is that in the US, in many areas, cycling is seen merely as a recreational function. I think this may be the case in the UK as well. On continental Europe, the flatness of the terrain of some of the countries, and density of the cities and towns afford cycling as a credible means of getting around (combined with higher gasoline and parking prices).
But if you only view cycling as a recreation pursuit, then there isn't much impetus to allot time and money to design and build facilities more for getting people around, versus "nature trails" or "recreation trails". Ironically, you'll often see cyclists drive their bikes to and from the trailhead.
Couple observations:
1) Unless they get a dedicated phase, left turning bicyclists will need to potentially wait for the light twice, since they effectively have to cross the intersection twice. This is slower, albeit perhaps safer, than the bicyclist getting in the the left lane and turning like any other vehicle.
2) Unless turns for motor vehicles are phased separately the possibility of right hook-esque collisions remains, although the improved sight lines makes them less likely.
The video proposes doing both of these things in order to avoid such problems, so it seems like the guy has his bases covered. Whether such phasing is practical in a real world situation is another matter entirely. If we assume this intersection is to have protected lefts, it would have a full FIVE phases - one for bikes and peds, one for through and right turns on each street, one for left turns on each street. That can get pretty cumbersome as everyone's slice of the pie shrinks an more of it is lost to clearance intervals. Seems to me this would be far more practical if one or both of the intersecting streets are one way (for motor vehicles, at least - there can still be a contraflow bike lane).
Yuck.
Vancouver remodeled the Burrard/Cornwall intersection last year, just southwest of downtown. Part of the plan for Cornwall was to install a protected bike lane that would continue over the Burrard Bridge.
Here's the intersection with its new protected bike crossings. The bike crossings have their own signals, and movements to Cornwall (the street to the left) is restricted to green-only (no turn on red).
Also, the bus from the left is sitting in the crosswalk. The white line in front of it is the eastern transverse line for the crosswalk.
(https://c2.staticflickr.com/6/5573/14937657987_bef9a989f2_o.jpg)
Image from Kathleen Corey (https://www.flickr.com/photos/95010596@N06/) or Flickr.
There are other protected crossings across the city. Here are a couple more examples:
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fstatic1.squarespace.com%2Fstatic%2F505c9118e4b08da3b4045056%2Ft%2F53e2c8fee4b0d805f787e30f%2F1407371551123%2F%3Fformat%3D750w&hash=fd584737e0a070da81fe1fe51263400ffead9fbc)
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fstatic1.squarespace.com%2Fstatic%2F505c9118e4b08da3b4045056%2Ft%2F53e2c5a9e4b071fc79eb3893%2F1407370666929%2F9bikecouver.png%3Fformat%3D500w&hash=6866e384570eba02fa1f55a896883bef94f20344)
Last two photos from Aaron Dixon (http://thestarfish.ca/home/2014/8/bikecouver-a-photo-essay) of Bikecouver.
It'll be interesting to see what Salt Lake City's experience will be. I also know that Davis, CA is looking at building at least one intersection like this as well.
Quote from: jakeroot on October 15, 2015, 11:10:05 PM
There are other protected crossings across the city. Here are a couple more examples:
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fstatic1.squarespace.com%2Fstatic%2F505c9118e4b08da3b4045056%2Ft%2F53e2c8fee4b0d805f787e30f%2F1407371551123%2F%3Fformat%3D750w&hash=fd584737e0a070da81fe1fe51263400ffead9fbc)
Looks like the bicyclist is past the stop line here, and encroached into the right lane of the roadway.
Quote from: jeffandnicole on October 16, 2015, 11:38:16 AM
Quote from: jakeroot on October 15, 2015, 11:10:05 PM
There are other protected crossings across the city. Here are a couple more examples:
http://static1.squarespace.com/static/505c9118e4b08da3b4045056/t/53e2c8fee4b0d805f787e30f/1407371551123/?format=750w
Looks like the bicyclist is past the stop line here, and encroached into the right lane of the roadway.
Yes that would seem to be the case. Maybe he's making a right turn?
Then again, cyclists in Vancouver are no better than any other city. Same amount of red light jumpers.