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Author Topic: Tucson Freeways  (Read 50300 times)

armadillo speedbump

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Re: Tucson Freeways
« Reply #125 on: February 20, 2023, 02:16:11 AM »

Downtown Link is now open from Broadway to 6th.  But the 6th St grade separation at the railroad tracks is still over a year away from completion.

Opened Friday:

https://twitter.com/Tucson_DTM/status/1626671453667209216

Here's a vid of the new section from a week ago.  LOL at the 30 mph speed limit.

https://twitter.com/Tucson_DTM/status/1624205336767766528

The comments sure support the stereotype of hardcore bike riders being perpetually angry, insufferable, self-centered jerks.
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74/171FAN

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Re: Tucson Freeways
« Reply #126 on: February 20, 2023, 07:01:19 AM »

Is the new section signed as an extended AZ 210?
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kwellada

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Re: Tucson Freeways
« Reply #127 on: February 20, 2023, 01:38:08 PM »

The comments sure support the stereotype of hardcore bike riders being perpetually angry, insufferable, self-centered jerks.

The Portlandia skit exists for a reason  :-D

I am very happy this little bypass is finally open. I need to navigate from north of downtown to the Aviation highway several times a week. Now, rather than taking Euclid/1st ave by the U of A (which is always quite busy), I can finally sneak past all that to get to Stone Ave instead. It might only be saving me 3 or 4 minutes, but it's less hectic right now. And for the bicyclists, I'm gonna still watch out for you even if you're angry!
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ztonyg

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Re: Tucson Freeways
« Reply #128 on: February 20, 2023, 07:37:25 PM »

The comments sure support the stereotype of hardcore bike riders being perpetually angry, insufferable, self-centered jerks.

The Portlandia skit exists for a reason  :-D

I am very happy this little bypass is finally open. I need to navigate from north of downtown to the Aviation highway several times a week. Now, rather than taking Euclid/1st ave by the U of A (which is always quite busy), I can finally sneak past all that to get to Stone Ave instead. It might only be saving me 3 or 4 minutes, but it's less hectic right now. And for the bicyclists, I'm gonna still watch out for you even if you're angry!

My only complaint about this is the pedestrian crossing at the end. I feel that they should've included a pedestrian tunnel or bridge instead.
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Duke87

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Re: Tucson Freeways
« Reply #129 on: February 20, 2023, 08:27:45 PM »

Is the new section signed as an extended AZ 210?

This project was funded by Pima County and managed by the City of Tucson without any involvement from ADOT. So I doubt it - it's not a state highway.
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DRMan

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Re: Tucson Freeways
« Reply #130 on: February 21, 2023, 08:47:13 AM »

I'm not a bicyclist, but I can see why they are concerned. Yes, the road is signed for 30 mph, but the design is more like a main artery, most of which are signed for 45 and see speeds of 50+.

I'm still pretty new around here, and I don't understand what they are trying to accomplish with Downtown Links. If they wanted a city street, they should have designed it as such. If they wanted a connector between AZ 210 to I-10, they should have actually connected the two roads (even the final product will not connect to I-10 but will dump traffic on St. Marys Rd.) and, if necessary, built the bike path elsewhere.

I know new freeways are a no-no in Tucson, but I'd be curious to hear about how we arrived at this design.
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KeithE4Phx

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Re: Tucson Freeways
« Reply #131 on: February 21, 2023, 10:23:00 AM »

I know new freeways are a no-no in Tucson, but I'd be curious to hear about how we arrived at this design.

Here's one major reason:  The proposed I-710 from the mid 1970s.

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DRMan

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Re: Tucson Freeways
« Reply #132 on: February 21, 2023, 10:37:43 AM »

I know new freeways are a no-no in Tucson, but I'd be curious to hear about how we arrived at this design.

Here's one major reason:  The proposed I-710 from the mid 1970s.



Ouch. Where would that interchange have been built?
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machias

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Re: Tucson Freeways
« Reply #133 on: February 21, 2023, 09:34:17 PM »

Is the new section signed as an extended AZ 210?

I think the intersection at Broadway is at Mile 2, so maybe someday it may be signed as AZ 210, but itís all local money right now. At the other end you can definitely tell where ADOT maintenance hands off to the City of Tucson or Pima County (I donít know which). The signs go to crap and the pavement is just a suggestion of blacktop over kitty litter.
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Sonic99

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Re: Tucson Freeways
« Reply #134 on: February 22, 2023, 03:13:26 AM »

I know new freeways are a no-no in Tucson, but I'd be curious to hear about how we arrived at this design.

Here's one major reason:  The proposed I-710 from the mid 1970s.



Ouch. Where would that interchange have been built?

From Arizona Roads...

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DJStephens

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Re: Tucson Freeways
« Reply #135 on: February 22, 2023, 12:06:11 PM »

    Complicated by the presence of the Southern Pacific RR main line.  Most likely that is why the I-10 alignment is shifted so much in the diorama.   Virtually almost nothing on I-10, in this I-710 interchange area, has changed since it's original construction.  Apart from covering the original concrete with asphalt.  All the original elements are still there.  The bridges, the shoulders, the ramps, even the truss gantries and light poles.  The original signage is gone, replaced by less than optimum clearview. There was a pair of bridges built over Alvernon Way, with an unused inner lane, in each direction.  And there was the downtown rehabiliation of I-10 E of I-19, believe in the nineties.
    Yep, Tucson is lacking in freeway mileage.  It should have had more, including the 710 spur to the University and downtown.   In addition a I-610 partial belt could have been done, circa 1970, by preserving ROW along the foothills in the north, along Houghton in the east, and arcing over to 19 in the south.    Would not  have pursued anything to the west or south of 10, north of the 19 interchange.  ADOT did do a fairly decent rebuild of the 10/19 interchange.  They do have a fairly good gridiron in the east, which has "saved" their asses, to a point.   
« Last Edit: February 22, 2023, 12:11:17 PM by DJStephens »
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Roadwarriors79

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Re: Tucson Freeways
« Reply #136 on: March 25, 2023, 09:57:48 PM »

Tucsonans can complain till the end of time, as far as the Downtown Links is concerned. I've driven it a couple times. It could have been so much better.

I was also on Tangerine last week. There's a milepost 34 in both directions in the Oro Valley area. How long have those mileposts been there?
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machias

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Re: Tucson Freeways
« Reply #137 on: March 27, 2023, 01:05:16 AM »

Tucsonans can complain till the end of time, as far as the Downtown Links is concerned. I've driven it a couple times. It could have been so much better.

I was also on Tangerine last week. There's a milepost 34 in both directions in the Oro Valley area. How long have those mileposts been there?

Yeah, I guess Downtown Links will help some but it could have been so much better. And I guess there's been quite a few accidents already at the intersection with Broadway.
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KeithE4Phx

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Re: Tucson Freeways
« Reply #138 on: March 27, 2023, 01:27:02 AM »

I was also on Tangerine last week. There's a milepost 34 in both directions in the Oro Valley area. How long have those mileposts been there?

The part of Tangerine Rd where that milepost is located is unsigned AZ 989.  I believe it's only ADOT-maintained west of AZ 77, over the Big Wash bridge, for about a mile and a half.  I think there's a Milepost 35 posted as well. 

AZ 989/Tangerine Rd was proposed about 20 years ago as part of a system of freeways for the Tucson area.  However, mentioning Tucson and freeways in the same sentence is a major local no-no, other than those that have already been built.
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machias

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Re: Tucson Freeways
« Reply #139 on: April 30, 2023, 07:06:17 PM »

Does anyone know the history around some of the overhead signing practices in the city of Tucson? There's some poorly designed overhead signs at the Golf Links Rd and Alvernon Rd interchange with AZ SR 210/Aviation Highway. At first I thought it was something the city or county did (in regards to abbreviations), but looking back at historical views on Google Street View, it looks like the newish signs using "NB" (for northbound) are just poor copies of what was there before, in what seems to be ADOT button copy.  With the excellent ADOT signing practices throughout the state, I find it hard to believe they would put these signs up back in the day. Anyone know the history?

2017
https://www.google.com/maps/@32.1906748,-110.9073196,3a,75y,233.32h,88.11t/data=!3m7!1e1!3m5!1svi5B8rfhTj0iO0-w7tlxwQ!2e0!5s20170501T000000!7i13312!8i6656

Today
https://www.google.com/maps/@32.1906977,-110.9073305,3a,75y,233.32h,88.11t/data=!3m6!1e1!3m4!1sfO7yHjRGOjDwlF5V3Vg11Q!2e0!7i16384!8i8192

The AZ SR 210 marker has been added in the last year or so. A very small improvement.
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DRMan

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Re: Tucson Freeways
« Reply #140 on: May 01, 2023, 12:27:18 PM »

Does anyone know the history around some of the overhead signing practices in the city of Tucson? There's some poorly designed overhead signs at the Golf Links Rd and Alvernon Rd interchange with AZ SR 210/Aviation Highway. At first I thought it was something the city or county did (in regards to abbreviations), but looking back at historical views on Google Street View, it looks like the newish signs using "NB" (for northbound) are just poor copies of what was there before, in what seems to be ADOT button copy.  With the excellent ADOT signing practices throughout the state, I find it hard to believe they would put these signs up back in the day. Anyone know the history?

2017
https://www.google.com/maps/@32.1906748,-110.9073196,3a,75y,233.32h,88.11t/data=!3m7!1e1!3m5!1svi5B8rfhTj0iO0-w7tlxwQ!2e0!5s20170501T000000!7i13312!8i6656

Today
https://www.google.com/maps/@32.1906977,-110.9073305,3a,75y,233.32h,88.11t/data=!3m6!1e1!3m4!1sfO7yHjRGOjDwlF5V3Vg11Q!2e0!7i16384!8i8192

The AZ SR 210 marker has been added in the last year or so. A very small improvement.

Not sure about the history, but Tanque Verde Rd also has some funky looking signage at the Wrightstown Rd intersection.

https://goo.gl/maps/cf3az8bbkf3gVuiRA

https://goo.gl/maps/wwZQDA9y2gybWKjg7

Again, the old signs looked better (but aging) but they went away in late 2016/early 2017 based on Street View:

https://goo.gl/maps/tpAmFwnVZULg9Fr18

https://goo.gl/maps/r9UM6PY6LvD5xaDB9



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brad2971

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Re: Tucson Freeways
« Reply #141 on: May 02, 2023, 12:06:36 AM »

Is the new section signed as an extended AZ 210?

I think the intersection at Broadway is at Mile 2, so maybe someday it may be signed as AZ 210, but itís all local money right now. At the other end you can definitely tell where ADOT maintenance hands off to the City of Tucson or Pima County (I donít know which). The signs go to crap and the pavement is just a suggestion of blacktop over kitty litter.

Frankly, now that the connection between Downtown Links and SR 210 is finished, ADOT should just offer to give SR 210 to Tucson and put their Tucson freeway chapter into the history books where they belong. Tucson has amply demonstrated that their traffic gets along just fine, thankyouverymuch, without those extra freeways beyond I-10 and I-19.
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SalvadorMFA

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Re: Tucson Freeways
« Reply #142 on: May 03, 2023, 12:25:40 AM »

ADOT added the Kino Parkway TI, the Country Club TI, and the I10/Alvernon/Future SR 210 Interchange to their Tentative Five-Year Program. If the board approves this on June 16th, we should see some improvements in the next 5 years.

https://azdot.gov/planning/transportation-programming/tentative-five-year-program
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707

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Re: Tucson Freeways
« Reply #143 on: May 08, 2023, 03:52:28 PM »

I find it hilarious how Tucson is so anti-freeway, yet most people I've talked to in Tucson have complained and ranted to me how there should be freeways because they hate the traffic. Can't say I pity them, they're bringing it on themselves and made their own bed. It's their own choice. They voted and decided on no freeways.
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jakeroot

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Re: Tucson Freeways
« Reply #144 on: May 09, 2023, 02:45:48 AM »

I would think most issues in Tucson could be fixed through individual intersection modifications, such as an extra lane in places.

My worry with building more freeways in Tucson would be changes to the fabric of the city; changes in property values, changes in zoning, traffic pattern changes, unused capacity in some places and insufficient capacity in others, not to mention immense amounts of land expropriation. It would take a long time to iron everything out, and I'm just not sure it would be worth it.

If I'm honest, I think people in Tucson need to step back and take a look at the bigger picture: taking more than one cycle to get through a light does not mean traffic is bad, or that a freeway is needed. And in fact, I think credit needs to be given to the Tucson DOT for the work they do on the arterial network; few cities in the US have as high of a capacity arterial network as Tucson.

Can a local (I'm not one) actually point to a specific road that should/could be replaced by a freeway?

machias

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Re: Tucson Freeways
« Reply #145 on: May 10, 2023, 12:50:53 AM »

I would think most issues in Tucson could be fixed through individual intersection modifications, such as an extra lane in places.

My worry with building more freeways in Tucson would be changes to the fabric of the city; changes in property values, changes in zoning, traffic pattern changes, unused capacity in some places and insufficient capacity in others, not to mention immense amounts of land expropriation. It would take a long time to iron everything out, and I'm just not sure it would be worth it.

If I'm honest, I think people in Tucson need to step back and take a look at the bigger picture: taking more than one cycle to get through a light does not mean traffic is bad, or that a freeway is needed. And in fact, I think credit needs to be given to the Tucson DOT for the work they do on the arterial network; few cities in the US have as high of a capacity arterial network as Tucson.

Can a local (I'm not one) actually point to a specific road that should/could be replaced by a freeway?

I've lived in Tucson for over two years, and comparatively speaking, traffic is not bad here. There are a few projects that need to be finished, for example there's a gap in the widening of Houghton Rd. along the east side of the city that would fix things in that area a lot. The city maintained portion of SR 210 Aviation Hwy desperately needs repair. Irvington Rd. east of Davis-Monthan AFB needs widening as well. The city and Pima County have both made some interesting design choices in some intersections that you don't really see elsewhere (Valencia and Kolb come to mind), but overall traffic moves well for a city this size.

I've noticed two things that contribute to "bad traffic": protected left turns are at the end of a signal cycle within the city limits, with flashing yellow arrows preceding them. There are many intersections where it's double left turn lanes in each direction and the sight lines for a confident turn with the flashing yellow are not always there. As an almost civil engineer that didn't finish his degree, I'm surprised at some of the choices for flashing yellow double-left turn lanes. And secondly, speed limits in parts of the city that are basically open desert or 3 or 4 lane in each direction arterials are set artificially low. The new stretch of the Houghton Rd arterial south of I-10 is a prime example: the speed limit is posted at 45 MPH. Once you come to the end of the arterial and join the older two lane roadway, the speed limit increases. There are many places where the speed limits seem low or even arbitrary, and this creates the effect of drivers ignoring all speed limits. 
« Last Edit: May 10, 2023, 01:02:48 PM by machias »
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ztonyg

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Re: Tucson Freeways
« Reply #146 on: May 16, 2023, 10:00:51 PM »

I would think most issues in Tucson could be fixed through individual intersection modifications, such as an extra lane in places.

My worry with building more freeways in Tucson would be changes to the fabric of the city; changes in property values, changes in zoning, traffic pattern changes, unused capacity in some places and insufficient capacity in others, not to mention immense amounts of land expropriation. It would take a long time to iron everything out, and I'm just not sure it would be worth it.

If I'm honest, I think people in Tucson need to step back and take a look at the bigger picture: taking more than one cycle to get through a light does not mean traffic is bad, or that a freeway is needed. And in fact, I think credit needs to be given to the Tucson DOT for the work they do on the arterial network; few cities in the US have as high of a capacity arterial network as Tucson.

Can a local (I'm not one) actually point to a specific road that should/could be replaced by a freeway?

I lived in Tucson for 6 years and have lived in Phoenix for 22. Tucson has the best arterial network in the state hands down. Phoenix's arterial network is awful (especially in the city of Phoenix which looks like they hired kindergarten traffic engineers compared to Tucson). The freeway network in Phoenix is such a necessity because the arterial network is/was horrible. There are some exceptions. Hayden Rd in Scottsdale flows like a Tucson arterial (although has far fewer access points). The same with Shea Blvd east of Loop 101 (also in Scottsdale). But most of the major arterials in Scottsdale / Phoenix / Tempe / Mesa / Chandler / Gilbert / Glendale / Peoria / etc. are a maze of streets widening and narrowing at municipal boundaries, traffic signals that aren't really phased / timed / coordinated, and overall traffic doesn't move well on them. 
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DRMan

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Re: Tucson Freeways
« Reply #147 on: May 17, 2023, 09:24:49 AM »

I've been in the Tucson area for almost three years now, and I agree that the arterial network generally works very well. It would be great to have a little more consistency in things like permissive left turns.

I can't imagine how different the community would be with a freeway network. I'd take Tucson over Phoenix any day.
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jdbx

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Re: Tucson Freeways
« Reply #148 on: May 17, 2023, 05:20:02 PM »

I would think most issues in Tucson could be fixed through individual intersection modifications, such as an extra lane in places.

My worry with building more freeways in Tucson would be changes to the fabric of the city; changes in property values, changes in zoning, traffic pattern changes, unused capacity in some places and insufficient capacity in others, not to mention immense amounts of land expropriation. It would take a long time to iron everything out, and I'm just not sure it would be worth it.

If I'm honest, I think people in Tucson need to step back and take a look at the bigger picture: taking more than one cycle to get through a light does not mean traffic is bad, or that a freeway is needed. And in fact, I think credit needs to be given to the Tucson DOT for the work they do on the arterial network; few cities in the US have as high of a capacity arterial network as Tucson.

Can a local (I'm not one) actually point to a specific road that should/could be replaced by a freeway?

I lived in Tucson for 6 years and have lived in Phoenix for 22. Tucson has the best arterial network in the state hands down. Phoenix's arterial network is awful (especially in the city of Phoenix which looks like they hired kindergarten traffic engineers compared to Tucson). The freeway network in Phoenix is such a necessity because the arterial network is/was horrible. There are some exceptions. Hayden Rd in Scottsdale flows like a Tucson arterial (although has far fewer access points). The same with Shea Blvd east of Loop 101 (also in Scottsdale). But most of the major arterials in Scottsdale / Phoenix / Tempe / Mesa / Chandler / Gilbert / Glendale / Peoria / etc. are a maze of streets widening and narrowing at municipal boundaries, traffic signals that aren't really phased / timed / coordinated, and overall traffic doesn't move well on them. 

I lived in Scottsdale in the early 90's, before Loop 101 was anything more than the Price Freeway on the East side of the valley, and the 51 ended at 32nd St just beyond the Dreamy Draw.  I remember well what a nightmare it was to get from anywhere near downtown Phoenix or the West Valley to our place which was near Scottsdale Rd. and Chaparral.  Drives that would take 30-45 minutes in those days can now be accomplished in 15-20.
« Last Edit: May 17, 2023, 07:36:31 PM by jdbx »
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jakeroot

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Re: Tucson Freeways
« Reply #149 on: May 17, 2023, 06:40:47 PM »

I've lived in Tucson for over two years, and comparatively speaking, traffic is not bad here. There are a few projects that need to be finished, for example there's a gap in the widening of Houghton Rd. along the east side of the city that would fix things in that area a lot. The city maintained portion of SR 210 Aviation Hwy desperately needs repair. Irvington Rd. east of Davis-Monthan AFB needs widening as well. The city and Pima County have both made some interesting design choices in some intersections that you don't really see elsewhere (Valencia and Kolb come to mind), but overall traffic moves well for a city this size.

I've noticed two things that contribute to "bad traffic": protected left turns are at the end of a signal cycle within the city limits, with flashing yellow arrows preceding them. There are many intersections where it's double left turn lanes in each direction and the sight lines for a confident turn with the flashing yellow are not always there. As an almost civil engineer that didn't finish his degree, I'm surprised at some of the choices for flashing yellow double-left turn lanes. And secondly, speed limits in parts of the city that are basically open desert or 3 or 4 lane in each direction arterials are set artificially low. The new stretch of the Houghton Rd arterial south of I-10 is a prime example: the speed limit is posted at 45 MPH. Once you come to the end of the arterial and join the older two lane roadway, the speed limit increases. There are many places where the speed limits seem low or even arbitrary, and this creates the effect of drivers ignoring all speed limits.

I would also advocate for finishing the arterial routes that have not been widened, where it's wide on either side of a particular stretch. Needless bottlenecks are, well, needless bottlenecks. The unusual intersections, such as Valencia and Kolb, or Grand and Euclid, definitely deserve some commendation for innovation. Although I have to wonder if the extra amount of ROW required makes it worth it more than just once in a blue moon.

In terms of the signal operations, this is actually where Tucson is known for their creativity. They were one of the first to widely implement double left turns, and remain one of just a handful of cities that implemented permissive phasing even with double left turns. There have been quite a few studies early-on that showed a very small increase in accidents, if any at most intersections, but an impressive increase in capacity. I believe this policy (implemented sometime during the 1980s) is when the city started practicing lagging left turns as well. The city also experimented with a small gore area between the through lanes and double left turn lanes; this changes the left turn design from negative offset to either no offset or positive offset, improving visibility for left turning traffic dramatically. Both of these innovations are what made Tucson's intersections more successful than typical intersections in other cities IMO.

I know Tucson, in the last ten years, has started to change how their signals operate, with time-of-day phasing and flashing yellow arrows rather than 5-section "yield on green" type signals. Switching to lagging left turns EDIT: flashing yellow arrows technically eliminated one of the more annoying aspects of lagging green arrows with shared signal faces, which is that both directions have green arrows simultaneous with one another, regardless if it's necessary. We have this issue in Japan (complete with permissive double turns) where our green arrows are always at the end, and it's not always great for roads with uneven traffic flows. Thing is, I don't know if Tucson actually changed their signals to allow for "offset" green arrow phasing (where the green arrows come on at different times). If they haven't, I could see that being a smart change. I would also like to see wider implementation of left turn waiting boxes, other than just a couple spots along Speedway at the UA Campus.

Edit: massive brain-fart in the last paragraph. WTF... :-D
« Last Edit: May 20, 2023, 08:51:24 PM by jakeroot »
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