PennDOT District 6 announced it will reactivate the ramp meters at 14 on-ramps to I-476/Mid-County Expressway. The signals will come back online in phases from south to north beginning with the MacDade Boulevard, Baltimore Pike, and US 1 interchanges which operated from from 1999 to 2001 and from 2004 to 2008.
I-476 Ramp Meters to be Operational in Delaware and Montgomery Counties Starting in February and March to Enhance Travel and Safety (http://www.dot.state.pa.us/Penndot/Districts/District6/D6Media.nsf/cd20de0d8cd84b3785256d66005b622b/fed9a6ef9bebce42852576b80073d120?OpenDocument)
I didn't know that they weren't currently operating. I assumed that they were as I've been through there generally outside of rush hour (going to and from Philadelphia airport).
I can't say I'm too pleased with ramp meters. The flow on the mainline road usually improves by around 10%, but the waiting times at the ramps can be excessive, I have seen situations where traffic must wait 20 - 30 minutes to enter the freeway. That is totally unacceptable. Another problem is ramp meters can gridlock the surface streets around an interchange.
The side-effects of ramp meters are often so bad that they shouldn't implement them in some cases. The main problem is that the freeway has a lack of capacity, not the traffic entering the freeway. Another side effect is that people may use other interchanges, or surface streets to reach their destination, often on roads not designed for heavy traffic.
It's a matter of priority. If the priority is for the more important route (i.e. the freeway) and for fewer accidents, then ramp meters work and work well.
Quote from: mightyace on January 28, 2010, 06:34:59 PM
I didn't know that they weren't currently operating. I assumed that they were as I've been through there generally outside of rush hour (going to and from Philadelphia airport).
Same. Last time I was there (I live literally 1/2 mile away from I-476 exit 3) they appeared to be operating.
How does making people have to floor the accelerator because they're getting on a freeway from a full stop improve traffic flow? They would be better served by encouraging people to keep out of the right hand lane except when getting on or off or lengthening the acceleration lanes to make it easier to merge in.
They have Ramp meters on US 22 in the Lehigh Valley but they don't use them anymore.
Quote from: Nexis4Jersey on January 29, 2010, 07:29:20 PM
They have Ramp meters on US 22 in the Lehigh Valley but they don't use them anymore.
Does that highway still have ramps where you have to stop then floor it to try and get on, ramp meters or not?
(Just asking, I haven't been on all but the western few miles in 10 or more years.)
QuoteHow does making people have to floor the accelerator because they're getting on a freeway from a full stop improve traffic flow?
Let me ask this in response...which is better for traffic flow on the mainline: having one vehicle coming down the on-ramp at a time, or having the whole platoon coming down and attempting to merge at once?
QuoteThey would be better served by encouraging people to keep out of the right hand lane except when getting on or off or lengthening the acceleration lanes to make it easier to merge in.
Lengthening acceleration lanes I can agree with. Trying to change people's behavior when it isn't explicitly illegal (and trying to require people to move over would be a legal nightmare, IMO) is pretty much a non-starter, nevermind that you're artificially limiting your mainline capacity with such an attempt.
There's a spot on NY 590 south where a whole platoon comes down and attempts to merge at once, and while it doesn't flow at rush hour, that's probably due more to the narrowing of the road at I-490 than the platoon (and rush hour traffic isn't supposed to flow anyways - you don't design your roads for rush hour, at least we don't in NY). It flows pretty well the rest of the time, probably because people move over to let them on.
Remind me to never get onto I-476 from a ramp in the future. I don't think I could accelerate to highway speed in time to catch a gap in traffic to merge in when starting from a stop.
Quote from: deanej on January 30, 2010, 02:19:18 PM
Remind me to never get onto I-476 from a ramp in the future. I don't think I could accelerate to highway speed in time to catch a gap in traffic to merge in when starting from a stop.
That's just keeping alive an old freeway skill in the Northeast and Midwest. The used to be (and maybe still are) a lot of substandard, short freeway on in places like Pennsylvania. But, it's still not fun. But, it is a good excuse to have a car with a beefy V6 or V8. :sombrero:
Quote from: mightyace on January 29, 2010, 07:57:45 PM
Quote from: Nexis4Jersey on January 29, 2010, 07:29:20 PM
They have Ramp meters on US 22 in the Lehigh Valley but they don't use them anymore.
Does that highway still have ramps where you have to stop then floor it to try and get on, ramp meters or not?
(Just asking, I haven't been on all but the western few miles in 10 or more years.)
Oh it sure does. PA has more than enough of those to go around, and most northeastern states have at least a few.
QuoteHow does making people have to floor the accelerator because they're getting on a freeway from a full stop improve traffic flow?
It sounds to me that they're only using the meters during certain hours when traffic is so bad that even without the meters you'd probably be near a complete stop anyway because of the queue to get onto the highway.
Quote from: deanej on January 30, 2010, 02:19:18 PM
Remind me to never get onto I-476 from a ramp in the future. I don't think I could accelerate to highway speed in time to catch a gap in traffic to merge in when starting from a stop.
Once again, and I'm just guessing, since that isn't my side of the state, that the times when they're in use, "highway speed" probably isn't very fast due to congestion.
...complete geographic fail for me. I saw "I-x76" and "Blue Route" and thought all this was happening in Pittsburgh. Apparently I don't know the difference between I-376 and I-476. :ded:
Quote from: Scott5114 on February 01, 2010, 08:59:37 PM...complete geographic fail for me. I saw "I-x76" and "Blue Route" and thought all this was happening in Pittsburgh. Apparently I don't know the difference between I-376 and I-476. :ded:
There was talk back in the 80s and 90s about installing ramp meters on I-376.
PennDOT Moves Back I-476 Ramp Meter Reactivation in Delaware County to Feb. 16 Due to Impending Snowstorm (http://www.dot.state.pa.us/Penndot/Districts/District6/D6Media.nsf/cd20de0d8cd84b3785256d66005b622b/947eb1e94dbd74de852576c40071d394?OpenDocument)
Reacquired with my some of my missing maps, I found and had Brent scan the original I-476 Ramp Meter brochure I picked up in the early 1990s.
(//www.aaroads.com/forum_images/northeast/PADOT_ramp_meter_brochure.jpg) (//www.aaroads.com/forum_images/northeast/PADOT_ramp_meter_brochure.pdf)
Click on image for the PDF of the full brochure.
Jeff, you may use this for pahighways.com if you would like.
I also have two other similar brochures, one given out after the Blue Route section of Interstate 476 opened with ramp diagrams, and another for U.S. 202 reconstruction (when they modernized the section leading into the junction with I-76 and US 422). Additionally I have some Delaware County maps that show different interchange configurations for Interstate 476, and a tri-level stack interchange proposed with who knows what.
Where was the proposed tri-level stack located?
Thanks Alex. I'd appreciate if you could scan in that Blue Route brochure you mention with the ramp diagrams.
Your welcome Jeff, I will get the I-476 brochure scanned in for you tomorrow.
The tri-level stack on the 1976 Delaware County map was positioned just northeast of where the Reed Road under pass of I-476 is located: http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=upper+darby,+pa&sll=36.527295,-95.712891&sspn=33.391695,86.220703&ie=UTF8&hq=&hnear=Upper+Darby,+Delaware,+Pennsylvania&ll=39.953948,-75.336556&spn=0.00783,0.029225&t=h&z=16
Ramps from I-476 aim southward parallel to Darby Creek. I also found a 1959 Metropolitan Planning type map in the collection with the Upper Darby Expressway. The line for it continues north from where I-695 would turn east toward Philly. It does not represent the tri-level stack in this 1976 map however.
Quote from: AARoads on February 13, 2010, 01:05:00 AM
Your welcome Jeff, I will get the I-476 brochure scanned in for you tomorrow.
The tri-level stack on the 1976 Delaware County map was positioned just northeast of where the Reed Road under pass of I-476 is located: http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=upper+darby,+pa&sll=36.527295,-95.712891&sspn=33.391695,86.220703&ie=UTF8&hq=&hnear=Upper+Darby,+Delaware,+Pennsylvania&ll=39.953948,-75.336556&spn=0.00783,0.029225&t=h&z=16
Ramps from I-476 aim southward parallel to Darby Creek. I also found a 1959 Metropolitan Planning type map in the collection with the Upper Darby Expressway. The line for it continues north from where I-695 would turn east toward Philly. It does not represent the tri-level stack in this 1976 map however.
I don't know about a stack, but I know of a T-style interchange, proposed at the location you pointed out on the google map, connecting with the formentioned Upper Darby Expressway. That interchange stayed on local maps (for then proposed Blue Route) through the late 70s.
PennDOT Moves Back I-476 Ramp Meter Reactivation in Delaware County to Feb. 23 Due to Snow (http://www.dot.state.pa.us/Penndot/Districts/District6/D6Media.nsf/cd20de0d8cd84b3785256d66005b622b/f51df68b5540a978852576cc005d66e5?OpenDocument)
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.interstate-guide.com%2Fimages476%2Fi-476_exit_guide_cover.jpg&hash=9c50fea7f07765b2a90f6670e166666fdc9353ba) (http://www.interstate-guide.com/images476/i-476_exit_guide.pdf)
Click the image above to view a scan of the original Interstate 476 exit brochure published by PennDOT.
Blue Route Ramp Meters Back in Operation (http://www.delcotimes.com/articles/2010/02/25/news/doc4b85f94088dd3251921405.txt)
Ramp Meters Confusing? Just Read Signs (http://www.delcotimes.com/articles/2010/02/28/news/doc4b89f40f0a30c036729338.txt)
Quote from: PAHighways on February 28, 2010, 03:26:45 PM
Ramp Meters Confusing? Just Read Signs (http://www.delcotimes.com/articles/2010/02/28/news/doc4b89f40f0a30c036729338.txt)
We got similar ramp meters in the Phoenix area where they alternate the green for each lane, but in California, both lanes get the green at the same time (a dumb way of doing it), so you get two motorists jockeying to get ahead of each other before the ramp narrows to one lane on its final approach to the freeway. :pan:
well, California does have a drag-racing tradition! :-D
PennDOT to Activate I-476 Ramp Meters at Route 1, Route 3 and Route 30 Interchanges in Delaware County on March 23 (http://www.dot.state.pa.us/Penndot/Districts/District6/D6Media.nsf/cd20de0d8cd84b3785256d66005b622b/7acf5f5be6dbd67b852576e900531296?OpenDocument)