Talk:Diverging diamond interchange

message: Either the date for the Missouri interchange or Google street view is wrong.
http://maps.google.com/maps?q=I-44+and+Route+13,+springfield,+missouri&hl=en&ll=37.214199,-93.311477&spn=0.011381,0.065103&sll=37.0625,-95.677068&sspn=52.240038,133.330078&t=h&hnear=Missouri+13+%26+Interstate+44+Business,+Springfield,+Greene,+Missouri+65802&z=15&layer=c&cbll=37.214186,-93.311469&panoid=wVWxeYT3eBU5UYYYkqLJmQ&cbp=11,262.47,,0,-3.32 
says August 2009. It doesn't show the new imagry from the Wikipedia page.  — Preceding unsigned comment added by 66.190.88.135 (talk) 02:07, 21 March 2012 (UTC)
replies: text: The link provided is at the intersection of Business Route I-44, not the intersection at the actual Interstate noted in the article.--75.31.191.6 (talk) 13:19, 4 September 2012 (UTC)
thread_title: Dates wrong?

message: I removed the Kansas City link as its shows only a diamond interchange.  I do not believe this is helpful to the article and the information provided in the main text is, in my opinion, adequate for providing the proposed location.  Just let me know if you disagree. --Thisisbossi 10:28, 28 August 2006 (UTC)
thread_title: Untitled

message: The interchange at * is not a diverging diamond, rather it is a stack modified with left-hand exits, similar to one in Rochester.  As a result, I have removed this erroneous entry. Snickerdo 02:49, 30 August 2006 (UTC)
replies: text: I had added it because the movements are the same, though it is completely grade-separated rather than signalised.  I feel it belongs, but I'll let it go unless anyone else feels the same. --Thisisbossi 10:31, 30 August 2006 (UTC)
replies: text: It is certainly a unique interchange, but kind of goes against the idea of a diverging diamond because all directions are free-flow.  A note about this interchange would certainly be a worthwhile addition to the stack article, however. Snickerdo 22:23, 30 August 2006 (UTC)
replies: text: I am not sure I could call that a stack though.  It really doesnt have the lanes stacking on top of each other.  Rather it is low lying and offers the advantage of not having a lot of height but able to squeze into it rather easily.  In Grand Rapids, MI we have a similar one and it is in the middle of the downtown.  Our downtown at the time had very few tall buildings so they used this design to keep it lower.  Personally I think if we metion it I would put it in the cloverleaf interchange since it has 8 ramps.  --Mihsfbstadium 23:41, 25 January 2007 (UTC)
replies: text:  But then, using your definition of what they are, stack interchanges are merely a subset of the more generic 4-way [semi] directional interchange.  e.g. I-64 & I-270 in St. Louis never exceeds 3-levels; I-94/I-90 & I-290 in Chicago is only 2-levels and is more characteristic of a pinwheel.  Topology shows that all these interchanges function in the same way. --Millbrooky 06:07, 15 April 2007 (UTC)

text: Or another idea for what these interchanges should be called: "Weaving Stack Interchange".  They do seem to form a basket weave of sorts. --Millbrooky 06:07, 15 April 2007 (UTC)
thread_title:  Baltimore Link at Bottom of Page 

message: GalootRob recently added a mention that a Gilbert Chlewicki "first introduced" this concept.  While the paper appears to give the impression that this is correct, I must nonetheless wonder how the Versailles interchange was constructed prior to 2003 if this configuration hadn't been invented yet?  Would it be more correct to say "first introduced into the United States", perhaps?  ...But even moreso, it may be more accurate only to say that he was first to present a paper on it within the United States, as surely Americans would have been aware of a new interchange configuration in use over in Versailles.  We share all sorts of info when it comes to feats of transport engineering. --Thisisbossi 23:12, 17 January 2007 (UTC)
replies: text: OK, after checking with the author I have a bit more understanding.  Yes, Versailles came first; but he's the first one who really got to thinking about potential applications in America.  I've modified the history a bit to hopefully better reflect this.  --Thisisbossi 05:18, 24 January 2007 (UTC)

text: Thanks! I am not sure which of the three came first and second... I'll add them in and tweak the article accordingly.  This is a fine example of how much more communication transportation engineers need both domestic and abroad! I may have to throw these two interchanges onto my sight-seeing list for next year... --Bossi (talk • gallery • contrib) 22:49, 29 January 2008 (UTC)
thread_title:  History 

message: Text under Advantages states, "It reduces the number of lanes for overcrossing or bridges..." What's an "overcrossing" and how exactly would it differ from a bridge?  Or is that just redundant? --Wlindley (talk) 01:14, 16 January 2008 (UTC)
thread_title:  Overcrossings? 

message: Construction has started on the new DDI at I-270 and Dorsett Road in St. Louis County.
70.133.171.247 (talk) 19:02, 29 November 2009 (UTC)
thread_title:  Updates 

message: There are - imho - illustrative animations on youtube, e.g. you tube com/watch?v=VOVcf0xoA0g Maybe someone who's allowed to might want to add it? 95.115.97.201 (talk) 21:55, 7 May 2010 (UTC)
thread_title:  Animation on Youtube 

message: The "Use in North America" section is bordering on example farm territory. Perhaps this could be broken out to a list of diverging diamond interchanges article?  It's the least readable portion of this article, which probably explains why the proposed DDI in Rochester was listed twice.  —Mrwojo (talk) 04:25, 20 June 2010 (UTC)
replies: text: Adjusted content accordingly. --Chaswmsday (talk) 16:37, 11 September 2012 (UTC)

text: Yes, that's one. --NE2 05:12, 20 November 2014 (UTC)
thread_title:  Use in North America 

message: In Grand Rapids, the interchange between I-196 and US-131 resembles a diverging diamond interchange, in that US-131 crosses over itself twice. Unlike a diverging diamond, however, this crossover uses overpasses instead of traffic lights, and the interchange has eight completely separate ramps instead of four Y-shaped ramps. All of the left-turning ramps exit on the left and merge on the left. Should this interchange be mentioned in the article? Here's the interchange on Google Maps: https://maps.google.com/?ll=42.973224,-85.676794&spn=0.013659,0.036135&t=m&z=15 —Tanner Swett (talk) 04:35, 25 April 2013 (UTC)
replies: text: In a way, its seems most similar to what is called in Wikipedia a "diverging windmill" interchange: the former configuration at the northeast I-95/I-695 interchange near Baltimore, MD (, ). -- Except that US 131 doesn't crossover. One of the roadgeek sites calls the old Maryland example a "twister". IMO, the Grand Rapids interchange is probably best characterized as a hybrid, as it's most likely too rare to be given a formal name. If it merits specific mention, it should probably be made under interchange (road) with the rest of the "freeway" to "freeway" hybrids. --Chaswmsday (talk) 17:43, 4 May 2013 (UTC)
replies: text: All right, it seems to me like the type of interchange in Grand Rapids is probably neither common enough nor unique enough to be worth a mention. Thanks for your comments. —Tanner Swett (talk) 02:16, 7 May 2013 (UTC)
thread_title:  The interchange between I-196 and US-131 in Grand Rapids, Michigan 

message: I was thinking, rather than lists attempting to be prose, would it not be best to convert the sections listing usages in North America to tables? We may even want to split it off into its own article as the number of DDIs in North America continues to grow. Perhaps something like this:
Missouri (example table)
City       	Intersection 	Date opened	Notes
Springfield	at           	           	First diverging diamond interchange in the United States
Kansas City	at Botts Road	           	Construction included a new bridge for the interchange
I'd love to hear some feedback on this. This could definitely improve the layout of the article, but I'm sure there's some amount of controversy to be had. Jon (aka Blurred203) holler 03:32, 1 December 2013 (UTC)
replies: text: I'd love to take work on this project to a subpage for completion, by the way, since mixing tables with prose for the same type content could certainly be jarring to users. Again, any and all feedback will be much appreciated. Jon (aka Blurred203) holler 03:57, 1 December 2013 (UTC)
replies: text: Do we need a comprehensive list? Why can't a non-exhaustive list of examples be just as educational to readers on what a diverging diamond is. We don't have a list of all of the diamond interchanges, all of the cloverleaves or all of the SPUIs, so such a list here is overkill. Imzadi 1979 →  20:46, 1 December 2013 (UTC)
replies: text: This is true...thanks for your input. As the use of DDIs in North America is still relatively new, and there are not that many, I would suggest we keep the list, or perhaps split it off into a "List of..." article. As the use of DDIs becomes normalized, I'd be fine with disposing of the list...but as of now, I almost feel it should be kept for the more adventurous readers. The table would also be much less exhaustive than reading prose on each DDI. Jon (aka Blurred203) holler 23:31, 1 December 2013 (UTC)

text: Also, I do agree that the "future" list is overkill, especially for stalled projects. At the very minimum, those probably need to be cut, regardless of what happens with the present DDIs. Jon (aka Blurred203) holler 23:35, 1 December 2013 (UTC)
replies: text: I don't think an exhaustive list is needed, neither as a "List of" split from this article nor as an embedded list here. Michigan left does not contain a full list of them, even though they're still pretty rare outside of Michigan where they are pretty common in the southern part of the state. Imzadi 1979 →  00:05, 2 December 2013 (UTC)
replies: text: I still don't see how it's exhaustive. There really aren't that many...the prose just makes it look that way. If we're going to keep the "listing" (if you will), the prose needs to go, in my opinion. Jon (aka Blurred203) holler 03:08, 2 December 2013 (UTC)
replies: text: Exhaustive = attempts to list every example. This article is trying to have an exhaustive list, which, when, there were only a few cases, was appropriate. Anyway, I agree that this should be cut down a lot. "Uses in North America" should be "Use in North America" and list the notable examples. I'd include the first DDI in Missouri and limit the prose to a discussion of how the concept spread to other states and provinces. I would limit this discussion to the first examples in other jurisdictions, or any that are notable for other reasons. The entire future section should be gutted, unless there are examples notable for some reason. By notable, I'm not employing the Wikipedia definition of coverage in third-party secondary sources, but rather the idea that there is something special that sets them apart, makes them worthy of noting. Imzadi 1979 →  03:43, 2 December 2013 (UTC)
replies: text: Apologies for the late response, been busy with school. It might be best to dispose of the future use section altogether, and switch the "Use in North America" section down to known special usages, not only in North America but also abroad. Jon (aka Blurred203) holler 05:30, 11 December 2013 (UTC)
thread_title:  Converting North American sections to tables 

message: The first ones were built in France. This is covered in the History section. A number have recently been built in North America. Unless more have been built outside of North America, I'd like to hear why the tag is warranted. --Triskele Jim 02:14, 15 December 2013 (UTC)
replies: text: It seems disproportional. There is one mention of the one in France then a huge list of US examples. --AdmrBoltz 02:23, 15 December 2013 (UTC)
replies: text: If diverging diamonds are being used elsewhere and are not included, then the globalize tag is valid. If all the examples except the few in France are on the US, is it really disproportionate? The list is getting a bit long, but I think they are still uncommon enough that the examples are usefull. --Triskele Jim 03:13, 15 December 2013 (UTC)
replies: text: The number is still growing. Important to know, France has built minimum 3 pcs in the 1970ies. The better design came up 2009 in the US. It is also important where and how the technic is beeing known and built. Many don't see the benefits and the better performance. --Hans Haase (talk) 01:20, 16 December 2013 (UTC)
thread_title:  Globalize tag 

message: Per the two above sections, I feel it is necessary to get some community-wide input on what to do (if anything) with the two sections in the article regarding the uses of DDIs. Should one or both sections be kept and improved, should one or both sections be reduced, or should one or both sections be removed completely? —203 22:20, 16 December 2013 (UTC)
thread_title:  RfC: Regarding the North American sections 

message: Since there are two issues at hand here, I've created 6 "bold-able" options to keep the discussion easy to follow.
* Option 1: Take no action; leave both sections as-is.
* Option 2: Keep all content in both sections and improve the global coverage.
* Option 3: Keep (and improve global coverage in) the current Uses section as-is, and reduce the Future section to verifiably notable uses.
* Option 4: Reduce both sections to verifiably notable uses.
* Option 5: Reduce the current Uses section to verifiably notable uses, and remove the Future section entirely.
* Option 6: Entirely remove both sections.
* Option 7: Create a Section "History" and ans sepratated article e.g. "list of DDIs" --Hans Haase (talk) 14:05, 18 December 2013 (UTC)
thread_title: Extra information

message: * Option 5 —203 22:20, 16 December 2013 (UTC)
thread_title: Survey

message: * Option 5 - Per the discussion two sections up, the Future uses section seems to contribute very little to the article and is a breeding ground for WP:CRYSTAL violations. In addition, many of the current uses outlined in the article are not especially notable. Therefore, the current Uses section should be reduced to unique construction processes, first occurrences, and other notable interchanges; the Future uses section should be removed entirely. —203 22:20, 16 December 2013 (UTC)
thread_title: Discussion

message: The only sources for this are primary (DcmiInterchange.com, patents, and an article written by the "inventor") and an article that ends up referencing Wikipedia. Barring any mention in other sources as a feasible alternative, it looks like self-promotion. --NE2 05:05, 19 November 2014 (UTC)
replies: text: @NE2: The DMCI ist a Patentes interchange with no known built sample in use. For this reaseon it has no own article. As a variant of the DDI with many similarities and some improvements it became section of the DDI's aricle. I don't know who who expanded it. On the other hand, we are collecting locations SPUIs and removed locations of the more rarely present DDIs from the article. So what is the encyclopedic value of those changes exept of poor infomation content and wasted time of readers an editors? --Hans Haase (talk) 14:24, 19 November 2014 (UTC)
replies: text: I have no opinion about listing, and that's not what this section is about. --NE2 14:49, 19 November 2014 (UTC)
replies: text: I support to keep the information about the DCMI in the article. Btw. the box below colapses the talk also. --Hans Haase (talk) 17:14, 19 November 2014 (UTC)
replies: text: Without any reasons for keeping it, your "support to keep" is meaningless. --NE2 00:35, 20 November 2014 (UTC)
replies: text: Patents are documents and as a variant of or similar to the DDI it is worth to be mentioned, but not focussed on. It also helps understanding the article. The fact the patent exists only with no practical use was the reason to integrate it into the article. I guess we should stop the libricide here. --Hans Haase (talk) 02:15, 20 November 2014 (UTC)
replies: text: By calling me a book burner, you've lost any claim to rationality here. --NE2 03:21, 20 November 2014 (UTC)

text: Sumary: We keep a minimalized note about in the article. @NE2: Always see it form the view of readers who have no idea from the stuff they read here and they should be informed what this is. – Done. --Hans Haase (talk) 17:05, 20 November 2014 (UTC)
replies: text: Reverted. Why should readers be informed about a fringe invention with no real-world examples? --NE2 21:46, 20 November 2014 (UTC)
replies: text: Let take a closer look on the topic to get a good article: The 1st thought to get a DDI in freeflowing traffic is to replace the 2 intersections by overpasses. This solution causes weaving. The patent confirms a possible solution to eliminate the weaving. In the US weaving is declared as a problem of interchanges. It may affect cloverleaf interchanges without single lane distributor carriage ways. Arround the DDI is not that much finished reserach as about other road junctions. Now back from OR to SOURCES: The patent shows a existing concept for such variant. NICE to know. --Hans Haase (talk) 00:13, 21 November 2014 (UTC)
replies: text: What you are doing is classic original research. Please stop. --NE2 00:22, 21 November 2014 (UTC)
replies: text: No, it is exactly not. It is to differ between OR and sourced information. By bringing relevant and sourced information to the article, the reader is enabled to get this or another view on that he/she is reading. It is not to to bring a point of view. It is giving existing information only. Is it wrong? No. Does it not apply? No. What would be a reason to keep it of of the article? One reason to hide such information would be working in a business providing obsolete solutions being replaced by such. Now let's review prices for the reader of including or excluding it. When reading both sections: the created thought is is on the discussion only. It has been created by reading the article, falling under OR. The sourced information is in the article only. It is no OR. It lets the reader decide, to rate it. Another question the reader may ask himself: Why has the patent no practical use? Analyzing the sketch: how large a DMCI most be built to handle what speed of traffic safe, regarding jamming traffic behind overpasses and underpasses? After reading about the DCMI you better understand what a DDI is. The accusation of OR in the article is not true. Read twice! The article provides sourced information only. --Hans Haase (talk) 07:19, 21 November 2014 (UTC)
replies: text: OK, now it's just word salad that can be used to justify any fact being included in any article. --NE2 07:49, 21 November 2014 (UTC)
replies: text: Stop wiping and whipping, we are talking about the article. The talks sections above show why the DCMI is a section of this article. What are reasons to keep it out? --Hans Haase (talk) 14:20, 21 November 2014 (UTC)

text: It is not to rate about why but that it has no practical use. Junctions are the major bottleneck of roads. They are subject of civil engineering. I support a diversity of knowledge including there is and design with no practical use only. Even in the US variants of stack interchanges saving contruction costs and bringing performance with less documentation about. Many of these have been built, existing still today, due efficiency. In this point wikipedia is far away from the real world, practical use and existing research. --Hans Haase (talk) 12:03, 22 November 2014 (UTC)
thread_title: Moving DCMI to talk

message: * May be more costly than a standard diamond or diverging diamond.
Support removal—No real world example exists and we shouldn't just list hypothetical interchanges until one is being or has been built.  --WashuOtaku (talk) 02:12, 22 November 2014 (UTC)
replies: text: It is not to rate about why but that it has no practical use. Junctions are the major bottleneck of roads. They are subject of civil engineering. I support a diversity of knowledge including there is and design with no practical use only. Even in the US variants of stack interchanges saving contruction costs and bringing performance with less documentation about. Many of these have been built, existing still today, due efficiency. In this point wikipedia is far away from the real world, practical use and existing research. --Hans Haase (talk) 12:03, 22 November 2014 (UTC)
thread_title:  DCMI disadvantages 

message: A so-called  was removed from this article per the discussion in Talk section "RfC: Regarding the North American sections". While I don't disagree with the removal of an exhaustive list of examples, I feel that the removal of that content could have been handled in a more collegial manner. As we're all likely aware, much content on WP is unfortunately out-of-sync. It would be helpful to explicitly provide the last version(s) of this article containing the full example list, to allow editors to more easily make sure cited prose about individual diverging diamond interchanges exists in the appropriate road articles. It's also quite conceivable that readers, upon finding this article, might wish to find examples of DDIs. The "What links here" tool, while quite imperfect in the overabundance of links it returns, and probably not well known or used by casual readers, could allow at least some readers to find a list of examples. Thus...
The most complete list of DDIs (existing and planned) can be found at this version of the article.
More up-to-date information about the first DDI in Virginia can be found here.
More up-to-date information about the first DDI in Maryland can be found here.
We should also check that the appropriate road articles found, among other content, here, contain sourced information about individual DDIs. --Chaswmsday (talk) 16:35, 10 January 2015 (UTC)
replies: text: The reason for removing the list from the article was due planned interchanges, only. Today these interchanges were built. A chronological information can not be linked from other articles. What road or state has the most DDIs is not covered, too. The included template "Streets and roadways" also affects the list of links to the article caused by missing filters. --Hans Haase (有问题吗) 00:50, 13 January 2015 (UTC)

text: All Coordinates displayed in map material requires to list the coords in the article or separate articles linked to the article or category. By using existing templates, the only solution I see, is to hide or show a text section of use inside the article. The :template:Collapse top would fulfill all dicussed requirements. It keeps the visible text small, but if interested, readers can show detailled information of use. --Hans Haase (有问题吗) 12:22, 13 January 2015 (UTC)
thread_title:  Removal of {{tl|Example farm}} (re: RfC: Regarding the North American sections) 

message: In a sequence of edits currently ending here I tried with limited success to convey the idea that using a DDI with a cross-road that has bike lanes is disadvantageous.
Perhaps my troubles are rooted in the 'globalize/North America' template in place for this article.
Please take a look at a classical, urban intersection in Denmark. The blue line indicating a bike lane has a parallel one like it for the opposite direction of traffic. A larger intersection would have blue lines for all four traffic directions, forming a blue square. Fifty years of experience with bike lanes in Denmark have shown that it is exactly in the crossing areas colored blue here that vehicle/bike collisions occur (often fatally), whereas such collisions are rare outside those areas. So for a crossing road that has bike lanes, a DDI intersection that incurs four bike crossings instead of two for a traditional high-way crossing is a disadvantage. I am aware that I did not clearly communicate this in my edit summaries and that this is not explicitly supported by the source cited regarding pedestrians, and that the Danish interest in and experience with bike lanes is not universal.
But I consider the four versus two necessary bike crossings self-evident, with the necessary crossing of the on-ramp lane looking for example like this (with separate lights and lanes for pedestrians and bicyclists).
My attempt to introduce this bicycle aspect is motivated by a recent article in Ingeniøren, Now you will have to drive on the left side of the road (in Danish), about a planned change of a high-way crossing to use a DDI outside of Odense, Denmark. Incidentally, there the crossing road does not have bike lanes. If someone thinks this can be included in the article, then feel free to help out. Then perhaps one day that 'globalize/North America' template can be removed. Have a nice day. Lklundin (talk) 14:50, 14 April 2015 (UTC)
replies: text: Your "necessary crossing of the on-ramp lane" is not in fact necessary. This is another way of handling a bike lane at an onramp. --NE2 15:32, 14 April 2015 (UTC)

text: @Thebesteditorofeditors69420 I can confirm that this is not true. 2600:1700:9E21:6310:F995:230F:D55D:E8 (talk) 06:07, 27 June 2023 (UTC)
thread_title:  Disadvantages: Bike lanes 

message: *
Imzadi 1979 →  10:16, 12 January 2016 (UTC)
replies: text: Yes, it shows signal sequences, pedastrian walkways, safety and lots of experience on existing interchanges. --Hans Haase (有问题吗) 22:30, 13 January 2016 (UTC)
thread_title:  Possible resource 

message: At Interstate 95 at A1A in Nassau County. Work starts next week. Complete date set for 2020. JenniferRSong (talk) 00:59, 12 January 2017 (UTC)
thread_title:  Coming soon to Florida 

message: They built a new DDI in Calgary with a pretty nice fly-through video demonstration. See more at their website http://www.calgary.ca/Transportation/TI/Pages/Road-projects/Macleod-Trail-162-Avenue-S-Interchange.aspx 
Not sure if the Usage:Operational section includes this one for Canada, didn't want to change it in case it was.
184.69.38.246 (talk) 13:49, 14 August 2017 (UTC)
thread_title:  Calgary, Alberta 

message: Instead of the pictures of the Springfield DDI, I think we could take up less space and communicate the experience of driving through this type of interchange more effectively with a video. It does not necessarily have to be of the Springfield one, though; any DDI will do.
Dashcam footage taken while driving through it in various configurations would be best, although a regular old camcorder would do. It could be complemented by drone footage so we could get an idea of the overall traffic flow (preferably at rush hour). Daniel Case (talk) 00:06, 7 December 2017 (UTC)
replies: text: I can do this - either with dashcam footage, or with an overhead time-lapse of one of the DDIs in or near Springfield, MO. I’ll check in to the airspace restrictions and find one that’s suitable for filming during heavy traffic. LyndsySimon (talk) 22:11, 30 October 2020 (UTC)
replies: text: Done! LyndsySimon (talk) 01:24, 13 February 2021 (UTC)
thread_title:  Video idea 

message: any examples on maps or youtube from real life?  — Preceding unsigned comment added by Johnny Bin (talk • contribs) 15:32, 13 May 2020 (UTC)
thread_title:   double crossover merging interchange (DCMI) example ? 

message: Why is highway bus stops being appropriately sited outside the interchange listed as a disadvantage? If anything this just seems like good common sense, rather than an actual disadvantage or negative attribute. Pf1127 (talk) 06:15, 19 August 2020 (UTC)
thread_title:  Bus stops: Disadvantage?