New Green light go system coming to Pennsylvania roads

[Fntp]

There's a new type of system that will help move along traffic at busy intersections. This is something that was used in some intersections in the Pittsburgh area but is now going state wide. Here's an article about what it is

http://www.publicopiniononline.com/local/ci_26680582/penndot-has-10-milllion-local-traffic-signals

[NE2]

It's not a "new type of system", just signal coordination.

[jeffandnicole]

And signal coordination only works when the lights are close enough together.  If the lights are more than a mile apart, there's too many opportunites for people to enter/exit the roadway, slow down, speed up, etc, that it makes it difficult to coordinate lights not only on that street, but the other intersecting streets.

If there's a detour that'll put a lot more traffic on certain roads, that may help these lights move that traffic - although it'll be interesting to see how that truly works.  Since the municipality has to apply for the grant, there's only a hundred or so lights that can be accepted into the system, and there's thousands of traffic lights in some areas, it appears that at best this is going to be a very broken system of green-light-go coordination.

[Brandon]

And signal coordination only works when the lights are close enough together.  If the lights are more than a mile apart, there's too many opportunites for people to enter/exit the roadway, slow down, speed up, etc, that it makes it difficult to coordinate lights not only on that street, but the other intersecting streets.

If there's a detour that'll put a lot more traffic on certain roads, that may help these lights move that traffic - although it'll be interesting to see how that truly works.  Since the municipality has to apply for the grant, there's only a hundred or so lights that can be accepted into the system, and there's thousands of traffic lights in some areas, it appears that at best this is going to be a very broken system of green-light-go coordination.

Not necessarily.  It can be done for miles on end.

It could be done anywhere, even on a "jersey freeway".

[NE2]

Jersey freeways don't have lights.

[hotdogPi]

Jersey freeways don't have lights.

There is a traffic light for a U-turn on US 1 in Massachusetts, north of Boston. This section is a Jersey freeway from Saugus (full freeway) to the Danvers/Topsfield border (standard 2-lane road).

https://maps.google.com/maps?ll=42.528772,-70.993153&spn=0.001593,0.001709&t=h&z=19

This is probably the only exception.

[NE2]

"Jersey freeway" is a roadgeek neologism for a road that has unrestricted property access but is otherwise a freeway. A traffic light (other than at a drawbridge) introduces a gap in a freeway; therefore it does the same to a Jersey freeway. Of course you can Hump it up and make it mean just what you choose it to mean.

[froggie]

If the lights are more than a mile apart, there's too many opportunites for people to enter/exit the roadway, slow down, speed up, etc, that it makes it difficult to coordinate lights not only on that street, but the other intersecting streets.

A "green wave" can still be implemented on roads with longer spacing between signals.  With at-grade expressways, an advantage is that you don't have the constant exiting/entering from driveways and private business access points.  Going back to Pennsylvania, something like this would REALLY be useful on the US 222 Trexlertown bypass.

[Flyer78]

The system has been up and running for at least a year in the King of Prussia area (US 202) and more recently in Plymouth Meeting (Germantown Pike). So far, some days seem better than others. It definitely was a change to people that creep and anticipate the light, especially for turns and whether or not it was an advanced or delayed clearance.

It has made the most difference in KoP at the Gulph and Henderson road lights, allowing for longer protected left phases at each intersection.

[Fntp]

I Think that this is great because it will defiantly ease up traffic especially where I
I've at traffic gets crazy even though we already have the system running here in cranberry Pa it's going to be in more intersections that qualify for it. I'm not sure if this is used in other states because it did say that it was a state of the art type thing but maybe it is.