Posted on 09/16/2017 1:04:21 PM PDT by Tolerance Sucks Rocks
The Pennsylvania Department of Transportation (PennDOT) has announced the completion of the state's first-ever diverging diamond interchange (DDI), located on Interstate 70, according to Equipment World.
The DDI design eliminates left turns across oncoming traffic, improving vehicle flow and decreasing the chance of accidents.
The agency also chose the DDI configuration because it could use the former interchange's cloverleaf footprint, reducing the impact of construction on the area. PennDOT said it modified the traditional DDI design slightly.
Design is one way transportation agencies are combating gridlock resulting from increased traffic. Other tools in DOT arsenals are the expansion of the highways themselves and variable tolling policies to decrease congestion in high-travel areas.
Earlier this month, Virginia officials broke ground on a $500 million extension of Interstate 395 express lanes along an 8-mile stretch from Alexandria, VA, to the Washington, DC, border. The project is part of a $1.4 billion state program to improve travel between DC and Fredericksburg, VA. Elsewhere in the region, Interstate 270 in Maryland is gearing up for a $230 million overhaul in an effort to ease congestion on the corridor that connects with the Capital Beltway.
Using tolling or other fee-based systems as a strategy to thin rush hour traffic volume has also again become part of the discussion in New York City, as well as other metros where congestion causes lengthy commutes.
Gov. Andrew Cuomo has suggested using congestion pricing to reduce traffic flow through New York City, in this case by charging a premium to drive in and out of Manhattan during peak travel times. He's expected to announce specifics in January as part of his annual State of the State address. Previous plans for congestion pricing in New York City have failed, but Cuomo said the extra money could be used for city infrastructure upgrades, particularly throughout its aging subway system. New York City Mayor Bill de Blasio has said he opposes the idea.
Lee County, FL, has had success with one aspect of congestion pricing, and that is discounts for tolls at slower times as way to reduce traffic during peak periods. In the late 1990s, Lee County began offering 50% toll discounts to drivers who traveled during set periods before and after rush hour. The strategy has reduced traffic during peak travel times by up to 20%, according to the FHA.
The first DD interchange that I drove through was at I-84 and US 91 in Chubbuck, Idaho in July 2014. It surprised the heck out of me because I had no idea that the interchange had been rebuilt that way.
What a mess. For a small town there were a lot of accidents. Years before I moved there they had never had a traffic study and when they did it made it easier for driving but the locals were still in the habit of going thru the red lights. I learned to look both ways before going on a green light.
My impression of Branson has just been nudged even lower than it was to begin with. Wow. And also, yikes.
Why can't they just use a big "roundabout" and build a coliseum in the middle, and have gladiator fights there on weekends? But no, nobody listens to my traffic ideas...
The drivers going thru the red lights are in Spfld. In Branson the speed limit during the summer is usually below 25mph...LOL 3 million people visit every year last I heard.
The Branson tourists often go to Spfld Bass Pro. I love Branson...in the winter! It really is very family friendly and my favorite shop is(was?- I moved in 2010) the Alaska shop at the most eastern end. I don’t like the vegas lights but I didn’t go at night. Good rates for seniors.
Also loving blue grass I enjoyed “steal your dollar city” (silver dollar cityI), the re-enactments all over the place and most of all, the prairie grass. Lived in Spfld for 13 yrs and the best part was that it only took 20 minutes to cross it and then it was farm and country. My brother loved to fish so it’s a great place for the wife to shop and hubby to fish.
Can’t beat a full clover leaf.
I think roundabouts are great but for some reason some folks can’t stand them. I’ve never seen a backup at a roundabout.
Then you've never driven in New Jersey.
I liked the historical aspect of the Springfield area. I was actually exaggerating about Branson a bit. Maybe it is just a bit slow by my standards.
I would have driven to other historical areas such as Hannibal, St. Joseph, etc., if I had had the freedom to drive that far (I did not have that freedom at the time).
I missed the mother (father? parent?) of all Bass shops, but I heard it was great. Again it was beyond my control that I could not get to it. I will try to remember about that Alaska shop if I ever get a chance to go back.
I think if I could go back that I would give the country music halls more of a shot. I like country music so it would be OK. I think there are several things I could have done but it would take a second visit, and I do not know when that will occur.
All the people that I met in the area were all friendly and helpful, which is a big plus in my book.
Erma Gawd. I know the ones in Georgia...they are awful. PLUS they are part of the ridiculous perimeter lay out
My guess is you don’t live there now
Wisconsin:
Even though there is no other traffic, stomp on your brake at the last second and come to a full stop at the yield sign. Ponder the universe, wonder at the engineering miracle of pavement poured in a circle. Wait until some one else enters and then pull part way out. Stop, pause while traffic builds up. Ignore posted speed limit and accelerate all the way up to 5mph. Swerve between all the lanes while trying to remember which way you were going. Slow down and turn on blinker. Exit and drive to the next one with directional still on.
Well, thats the procedure for summer driving anyway. Weve developed an even better one for driving on the improperly plowed icy roundabouts.
They have some of these in Salt Lake City, and they’re not confusing at all. Traffic is well-channelled where lanes cross over and back, and it works very well with no turning across oncoming traffic on any route.
Interesting, while others are looking to design for solutions Cuomo's first thought was to fleece the public.
This is an efficient design. It simplifies the process of the ‘problematic’ left turn, especially for those who want to make a left turn onto the street after exiting the highway: these people will be able make a left turn without even stopping.
Also, anyone who ends up stopped at a redlight while waiting to enter the intersection only stops once. When the light turns green, everyone will make it through the intersection without suffering another red light.
I know of two diverging diamond interchanges here in GA, I use them almost daily. Tremendous improvement.
We had one of these interchanges installed near where I lived in Georgia. For years traffic in that intersection was a nightmare. After they put in the DD you could zip through in no time flat. It’s a stupid sounding idea that works brilliantly.
...
It costs much less to build, takes much less time to build, has higher throughput, and is safer.
I noticed the first one added a wide sidewalk, too, where there was none with the traditional design.
I don’t think I’ll blame that one on the design.
I have a cousin on my dad’s side who is a civil engineer with the NC DOT, we talk a fair amount, he’s my age and almost like a brother. He was talking about these things years ago. They’ve been implemented in NC, I’ve driven through a few of them. I can’t say I thoroughly grasp the benefit as it feels a little convoluted, but apparently it’s less costly and takes up less real estate than a cloverleaf while accomplishing the same goal. That’s my understanding at least.
They built one in my area. The original intersection/bridge crossed an interstate and at rush hour you’d have to wait 4 or 5 light changes to get through.
At the most it takes 2 light changes now.
Can’t beat a full clover leaf.
I think roundabouts are great but for some reason some folks can’t stand them. I’ve never seen a backup at a roundabout.>>> try doing a roundabout on the british wrong side of the raod with an american built car. regular driving was crazy but i just went thru the roundabout backwards. luckily no oncoming traffic in anquilla.
Supposedly getting one of these near me. It makes sense when you watch the videos, but the crossover sections give me the willies - reminds me of the old figure-8 racing that always turned into demolition derby.
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