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Baronjutter
Dec 31, 2007

"Tiny Trains"

Yeah, people not familiar with driving downtown where I live can get pretty confused or even panic and feel trapped because there's some pretty long stretches of no left turns and one way streets that finally end at an advance (protected left).

It's also really common to have no left turn signs along with times. So like "no left turns 4-6 mon-friday" or whatever. The honking you will hear when someone ignores this rule is instant and deafening.

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Varance
Oct 28, 2004

Ladies, hide your footwear!
Nap Ghost
Because looping around with right turns is such a hard concept...

--------

As part of a new skyscraper project (36 stories, new tallest building in Tampa :toot:), the City of Tampa is going to switch Cass St and Tyler St from their current one-way configuration to bi-directional traffic (Cass as the through street, Tyler dead-ending at the new skyscraper/Performing Arts Center). Only one problem...



The short-term solution is to maintain Cass and Tyler as one-way between Morgan and Jefferson, as to not break the funky intersection. Orange Ave needs to be disrupted as little as possible, as that's one of two main arterials leading to/from I-275 and I-4.

Varance fucked around with this message at 16:11 on Oct 17, 2013

Baronjutter
Dec 31, 2007

"Tiny Trains"

Specially when you're downtown with a grid of tiny blocks. Miss your turn? Better panic and block traffic for a whole cycle.

Why do people do this? I don't understand the psychology of a driver who missed their turn or are in the wrong lane and instead of just going with it, keeping calm and keeping traffic moving and just looping around, they'll STOP or suddenly try to make some ridiculously dangerous/illegal turn or maneuver that ends up not really saving them much time and fucks/stresses out everyone around them. It's not like being on a highway where missing your off-ramp can mean a 20 min drive to get back.

Missed your left? Just take the next one. Missed the driveway of the business? Just loop around. No left turn? loop around. Keep moving and loop!

NihilismNow
Aug 31, 2003

Baronjutter posted:

Why do people do this? I don't understand the psychology of a driver who missed their turn or are in the wrong lane and instead of just going with it, keeping calm and keeping traffic moving and just looping around, they'll STOP or suddenly try to make some ridiculously dangerous/illegal turn or maneuver that ends up not really saving them much time and fucks/stresses out everyone around them. It's not like being on a highway where missing your off-ramp can mean a 20 min drive to get back.

Missed your left? Just take the next one. Missed the driveway of the business? Just loop around. No left turn? loop around. Keep moving and loop!

It is really simple, they don't give a gently caress about anyone else. I want THIS left turn, NOW. Not in 5 minutes NOW. It doesn't matter if i block 50 cars from moving on this cycle, i want this turn.
It is the same with people stuck in the left lane going 10mph below the speed limit. There is no malice there, they just don't give enough of a gently caress about other people to be inconvenienced by moving 5 meters to the right. I have my car set on cruise control and i guess i am going to have to move to the left again in a few miles so why not stay in the left lane and dedicate spare brain cycles to whatsapp.

No my commute wasn't frustrating at all today, why do you ask?

Edit: I really need to rig up some dashboard cam to get shots of people tailgating each other at ~5 meters and 100kph in the left lane while the right lane is completely clear for hundred of meters or more.

NihilismNow fucked around with this message at 16:24 on Oct 17, 2013

Terminal Entropy
Dec 26, 2012

Varance posted:

Because looping around with right turns is such a hard concept...

That's a concept that didn't seem to exist when I visited the Bay area: no left turn cycles meant people darting out to make the left as soon as the light turned green to beat the through traffic, all this bookend with the hills of San Francisco and claustrophobic streets.

smackfu
Jun 7, 2004

Our problem with the GPS was that the big streets with traffic lights are correctly signed as "no left turn". But the smaller streets in between which don't have lights are not signed that way. Probably because you just can't turn left under most practical circumstances.

So while you should just turn right to make a left, the GPS keeps telling you to turn left on the small streets. Hard to make sense of if you aren't familiar with the area.

Baronjutter
Dec 31, 2007

"Tiny Trains"

So between where I live and downtown where 2 major 3 lane one-way streets with parking generally on both sides. Instead of taking out any of the parking, they removed a whole lane to put in a bike lane. These were already wide lanes with quite the gaps between the travel lanes and the parking, so bikes had ample space to ride quite comfortably. Now there's HUGE bike lanes separated from the travel lanes by a good 3' wide white painted buffer zone.

The problem is that these one-way streets have a few weird intersections and other one-ways that feed into them, so the bike lanes have to confusingly cross or split up in a few spots. And drivers are totally ignoring them and still driving as if it was a 3 lane road. It's a mix of heavy traffic and people not giving a gently caress, NO bikes using the bike lanes, and the lanes them selves being fairly confusing and not marked clearly enough. There's a really bad spot where the 3 lanes used to split up, 2 lanes flowing into a 4 lane bi-directional street, and 1 lane flowing into a 3 lane bi-directional street almost like a little off-ramp. Everyone was very used to this. Now it's just 2 car lanes and a bike lane, but everyone keeps driving in the bike lane thinking they need to be all the way over to the right to go where they need to go. The whole thing is on a hill and then a sharp turn so tons of drivers are driving in the bike lane, cresting the hill and turning the corner only to realize their super wide bike lane they were driving in is now a super narrow bike lane and they have to quickly merge to the left.

So far I've seen 2 people hit the curb or drive up onto the sidewalk and daily I see cars stopped at the end of the bike lane sitting there confused with their blinker on.

Before the car-lane width bike lane ends it sort of bubbles out a little, I guess for bikes to stop to cross the right most lane to go north instead of east. That's where everyone is hitting the curb, stopping, or merging in a panic and almost hitting the car to their left.


I don't know how they should have implemented the bike lanes. I think there needs to be a physical separation, a curb or some k-barriers or something. When you just toss some white lines on what has always been a travel lane people just ignore it. The problem is they can't put a barrier because there's still parking along some of the road. Useless parking in front of apartments and condos that all have off-street parking.


This is what the intersection looked like pre-bike lane. Now the right-most lane is a huuuuge bike lane that suddenly stops and narrows down to about 3' wide and people can not figure it out at all. Also anyone turning right on Stanley just drives in the bike lane and turns right like it's their own private little lane.

Baronjutter fucked around with this message at 17:31 on Oct 17, 2013

Kaal
May 22, 2002

through thousands of posts in D&D over a decade, I now believe I know what I'm talking about. if I post forcefully and confidently, I can convince others that is true. no one sees through my facade.

Baronjutter posted:

I don't know how they should have implemented the bike lanes. I think there needs to be a physical separation, a curb or some k-barriers or something. When you just toss some white lines on what has always been a travel lane people just ignore it. The problem is they can't put a barrier because there's still parking along some of the road. Useless parking in front of apartments and condos that all have off-street parking.

It sounds like a perfect opportunity for exchanging the street parking with the bike lane, and then separating the lanes. That way cars can access their parking spots, and establish a protected zone for bicyclists. Here's a picture of New York's approach to the same issue of converting a three-lane speedway to a slower two-lane with bicycling facilities:

http://www.streetsblog.org/2011/01/20/with-the-facts-in-dot-plans-more-improvements-for-prospect-park-west/

Kaal fucked around with this message at 17:50 on Oct 17, 2013

Jethro
Jun 1, 2000

I was raised on the dairy, Bitch!

Baronjutter posted:

So between where I live and downtown where 2 major 3 lane one-way streets with parking generally on both sides. Instead of taking out any of the parking, they removed a whole lane to put in a bike lane. These were already wide lanes with quite the gaps between the travel lanes and the parking, so bikes had ample space to ride quite comfortably. Now there's HUGE bike lanes separated from the travel lanes by a good 3' wide white painted buffer zone.

The problem is that these one-way streets have a few weird intersections and other one-ways that feed into them, so the bike lanes have to confusingly cross or split up in a few spots. And drivers are totally ignoring them and still driving as if it was a 3 lane road. It's a mix of heavy traffic and people not giving a gently caress, NO bikes using the bike lanes, and the lanes them selves being fairly confusing and not marked clearly enough. There's a really bad spot where the 3 lanes used to split up, 2 lanes flowing into a 4 lane bi-directional street, and 1 lane flowing into a 3 lane bi-directional street almost like a little off-ramp. Everyone was very used to this. Now it's just 2 car lanes and a bike lane, but everyone keeps driving in the bike lane thinking they need to be all the way over to the right to go where they need to go. The whole thing is on a hill and then a sharp turn so tons of drivers are driving in the bike lane, cresting the hill and turning the corner only to realize their super wide bike lane they were driving in is now a super narrow bike lane and they have to quickly merge to the left.

So far I've seen 2 people hit the curb or drive up onto the sidewalk and daily I see cars stopped at the end of the bike lane sitting there confused with their blinker on.

Before the car-lane width bike lane ends it sort of bubbles out a little, I guess for bikes to stop to cross the right most lane to go north instead of east. That's where everyone is hitting the curb, stopping, or merging in a panic and almost hitting the car to their left.


I don't know how they should have implemented the bike lanes. I think there needs to be a physical separation, a curb or some k-barriers or something. When you just toss some white lines on what has always been a travel lane people just ignore it. The problem is they can't put a barrier because there's still parking along some of the road. Useless parking in front of apartments and condos that all have off-street parking.


This is what the intersection looked like pre-bike lane. Now the right-most lane is a huuuuge bike lane that suddenly stops and narrows down to about 3' wide and people can not figure it out at all. Also anyone turning right on Stanley just drives in the bike lane and turns right like it's their own private little lane.
Is the pavement for the bike lanes painted green? If not, adding that should help. Also, having a period of increased enforcement by police would probably help folks figure out the change pretty quick.

E: also, what Kaal said.

Nintendo Kid
Aug 4, 2011

by Smythe

Kaal posted:

It sounds like a perfect opportunity for exchanging the street parking with the bike lane, and then separating the lanes. That way cars can access their parking spots, and establish a protected zone for bicyclists. Here's a picture of New York's approach:



Best part of it is that when you park your car, you're usually well out of any puddles and have more room to open your door without worrying about hitting people passing by or stuff on the curbside.

Baronjutter
Dec 31, 2007

"Tiny Trains"

I think the fact that street parking varies so much block to block makes that idea not work out so well.

Oh they've also taken MONTHS to just paint these lanes. Maybe the bike lanes will be painted one day. They handled the whole thing really badly. For almost a month there were just no lines on the road at all. Then little temporary dots. Then other dots showing where the bike lane will be. Then some line work, but not all. The thing's just been very very slowly forming over a ridiculously long time so who the gently caress knows.

Byers2142
May 5, 2011

Imagine I said something deep here...

NihilismNow posted:

... going 10mph below the speed limit...

... 100kph in the left lane...

That's an interesting commute you must have in the mornings...

Hedera Helix
Sep 2, 2011

The laws of the fiesta mean nothing!

Baronjutter posted:

So between where I live and downtown where 2 major 3 lane one-way streets with parking generally on both sides. Instead of taking out any of the parking, they removed a whole lane to put in a bike lane. These were already wide lanes with quite the gaps between the travel lanes and the parking, so bikes had ample space to ride quite comfortably. Now there's HUGE bike lanes separated from the travel lanes by a good 3' wide white painted buffer zone.

Do the bike lanes go in either direction, or are they one-way like the street is?

Baronjutter
Dec 31, 2007

"Tiny Trains"

Hedera Helix posted:

Do the bike lanes go in either direction, or are they one-way like the street is?

It's all one-way just like the streets

Lead out in cuffs
Sep 18, 2012

"That's right. We've evolved."

"I can see that. Cool mutations."




NihilismNow posted:

so why not stay in the left lane and dedicate spare brain cycles to whatsapp.

Because texting while driving is like drunk-driving levels of dangerous, and also illegal in most US states (and other countries)?

Lead out in cuffs
Sep 18, 2012

"That's right. We've evolved."

"I can see that. Cool mutations."




Kaal posted:

It sounds like a perfect opportunity for exchanging the street parking with the bike lane, and then separating the lanes. That way cars can access their parking spots, and establish a protected zone for bicyclists. Here's a picture of New York's approach to the same issue of converting a three-lane speedway to a slower two-lane with bicycling facilities:

http://www.streetsblog.org/2011/01/20/with-the-facts-in-dot-plans-more-improvements-for-prospect-park-west/



They just finished the first one of these in Vancouver, on Union Street between Main and Gore. It's really rather nice, although some drivers haven't quite adapted to it becoming a one-way yet (I saw at least one driving in the bike lane on the side of the road without parking).

It was much needed, though. That section of road saw 3,000+ cyclists per day, and about as many motorists. Apparently rush hour was a complete shitshow. I'll see if I can take a photo when I pass through there today or tomorrow.

Kaal
May 22, 2002

through thousands of posts in D&D over a decade, I now believe I know what I'm talking about. if I post forcefully and confidently, I can convince others that is true. no one sees through my facade.

Lead out in cuffs posted:

It was much needed, though. That section of road saw 3,000+ cyclists per day, and about as many motorists. Apparently rush hour was a complete shitshow. I'll see if I can take a photo when I pass through there today or tomorrow.

One of the cool things about this style of bike facility is that it actually increases the throughput of the road. It slows down vehicular speeds, but it is more than made up for with increased bicycle traffic and reduced vehicular congestion.

mamosodiumku
Apr 1, 2012

?
When you design a turn, do you usually try to keep it so it has a constant radius? Are there situations that may warrant changing how tight a turn is mid turn?

Lead out in cuffs
Sep 18, 2012

"That's right. We've evolved."

"I can see that. Cool mutations."




Kaal posted:

One of the cool things about this style of bike facility is that it actually increases the throughput of the road. It slows down vehicular speeds, but it is more than made up for with increased bicycle traffic and reduced vehicular congestion.

Yeah, it's removed one traffic lane (and made the road one way), but keeps it in the direction that most people go (to the viaduct onramp on the other side of Main Street). They did some pretty good stuff in this project overall: if you note the intersection of Union and Main on the map below, that's a weird 5-way with the onramp, and was one of the highest cycling accident locations in the city. They've now closed off Union to car traffic on the west side of Main, with a bike-passable traffic island in the middle of the intersection to reinforce that. They've also changed the light phasing to a 3 phase cycle that allows left turning traffic from Main to the viaduct to pass at the same time as cycle traffic from Union to Union.

E: If anyone's interested, the planning and background documents are all online here. The main plan PDF (10MB or so) is here.

The block of Union Street in question (also note the nasty intersection at Main):



Union Street before:



Union Street now, with bike lanes behind the parking:





As I said, though, a lot of motorists are still getting confused by the change to one way, and end up driving in that overly wide bike lane on the south side of the road.

E: Apparently, according to the plan, that's meant to be a shared lane. I guess the few cars I've seen on it weren't going that fast, and can afford to wait behind a cyclist for one block, especially given the 30 km/h speed limit.



This all raises another interesting question for Cichlidae: viaducts. That map shows the beginning of the Dunsmuir and Georgia viaducts into downtown. Here's the Google map link: http://goo.gl/maps/uqUBZ

As far as I can tell, they're somewhat redundant, since Pacific and Expo Boulevards directly underneath them actually have more capacity. Historically, I'm told they were built as the first step in driving freeways through the downtown core, a project which was killed by popular protests in the 60s and 70s. Right now, the City is looking into removing them over the next decade, citing extremely high maintenance costs, the eyesore factor (that part of downtown feels like something out of Judge Dredd to have to walk through), and the fact that they are occupying several blocks of what is now prime downtown real estate.

What are your feelings on this?

Lead out in cuffs fucked around with this message at 22:39 on Oct 19, 2013

Devor
Nov 30, 2004
Lurking more.

mamosodiumku posted:

When you design a turn, do you usually try to keep it so it has a constant radius? Are there situations that may warrant changing how tight a turn is mid turn?

There's several ways you can do horizontal curves:

Tangent - Curve - Tangent: This is the typical way that we do curves in Maryland. It's easy to lay out during design, keeps it simple during construction.

Spirals: Some jurisdictions use spirals - North Carolina, for instance. These are kind of like variable-radius curves that help you transition smoothly into and out of the curve. The idea is that this recognizes that drivers turn the wheel non-instantaneously, so it better matches the car's real path. It's also more pleasing to the eye.

Compound Curves: Sometimes due to the surrounding features or topography, it's desirable to use compound curves. A compound curve is when you have two curves going in the same direction back to back. AASHTO says that the ratio of the radii not exceed 1.5:1 - so you could have 600' radius into 900' radius.

Reversing Curves: These are somewhat unusual, because roadway curves are superelevated (think the banking at a circular racetrack), and when you have reversing curves it can be difficult to make this work correctly. You would typically have a short section of tangent between the reversing curves in order to allow for the superelevation transition.

Broken Back Curve: This is what you DON'T do. You never want to have two curves in the same direction separate by a tangent. This is because it violates driver expectiations, and causes crashes. Similarly, you wouldn't use compound curves going lowradius-higherradius-lowradius, even if it met the 1.5:1, because of the same problem - confuses drivers, causes crashes.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

mamosodiumku posted:

When you design a turn, do you usually try to keep it so it has a constant radius? Are there situations that may warrant changing how tight a turn is mid turn?

Devor did a great job of explaining it. From what I've designed, I typically do simple constant radii on low-speed urban roads, and spirals on freeways. Broken-back curves are really horrible; there's one on Route 9 where it goes over a bridge, a hundred feet of tangent in the middle of two huge curves. Even when I know it's coming, I still hit the rumble strips half the time.

Lead out in cuffs posted:

This all raises another interesting question for Cichlidae: viaducts. That map shows the beginning of the Dunsmuir and Georgia viaducts into downtown. Here's the Google map link: http://goo.gl/maps/uqUBZ

As far as I can tell, they're somewhat redundant, since Pacific and Expo Boulevards directly underneath them actually have more capacity. Historically, I'm told they were built as the first step in driving freeways through the downtown core, a project which was killed by popular protests in the 60s and 70s. Right now, the City is looking into removing them over the next decade, citing extremely high maintenance costs, the eyesore factor (that part of downtown feels like something out of Judge Dredd to have to walk through), and the fact that they are occupying several blocks of what is now prime downtown real estate.

What are your feelings on this?

I'd much rather have tunnels than viaducts, though they do have their place... and this isn't it. With that right of way and the (presumably) low volumes, you'd be better off with a boulevard or depressed freeway. Every bridge needs to be replaced at some point, and replacing viaducts while maintaining traffic is next to impossible.

Varance
Oct 28, 2004

Ladies, hide your footwear!
Nap Ghost

Cichlidae posted:

Every bridge needs to be replaced at some point, and replacing viaducts while maintaining traffic is next to impossible.
Seconding this. The downtown viaducts of the Selmon Crosstown Expressway in Tampa were just expanded from 2 to 3 lanes with new entrance/exit ramps and up-to-date safety features. Through the entire process, one half of each viaduct deck was completely torn up and rebuilt from scratch, while the other half remained open as a one lane 45MPH highway with no median or shoulder. The only way we pulled this off without having apocalyptic traffic jams is by having a third, reversible viaduct with LOS A capacity bypassing the construction zone, covering the traffic loads.

Old Viaduct:



New Viaduct:



"Suicide Ride":

Varance fucked around with this message at 01:55 on Oct 20, 2013

Cocoa Crispies
Jul 20, 2001

Vehicular Manslaughter!

Pillbug

Varance posted:

Seconding this. The downtown viaducts of the Selmon Crosstown Expressway in Tampa were just expanded from 2 to 3 lanes with new entrance/exit ramps and up-to-date safety features. Through the entire process, one half of each viaduct deck was completely torn up and rebuilt from scratch, while the other half remained open as a one lane 45MPH highway with no median or shoulder. The only way we pulled this off without having apocalyptic traffic jams is by having a third, reversible viaduct with LOS A capacity bypassing the construction zone, covering the traffic loads.

I took the top-level lane into town at about 10am last Friday, and it was amazing: no traffic, wide-open lanes, and I really really really wanted to take it at three-digit speeds.

It's kind of crazy how enormous it is though.

Arcturas
Mar 30, 2011

Cichlidae, what are the freeway overpass intersections where you drive on the wrong side of the street called? I remember a lot of discussion about them a few years ago in this thread, and while we've put a few in here in Salt Lake City, I hadn't driven on them before this weekend.

They work pretty well as long as you pay attention to the signs/lights/road, but they make me nervous about terrible drivers.

Continuous flow intersections?

What makes them work so well?

babyeatingpsychopath
Oct 28, 2000
Forum Veteran


Arcturas posted:

Cichlidae, what are the freeway overpass intersections where you drive on the wrong side of the street called? I remember a lot of discussion about them a few years ago in this thread, and while we've put a few in here in Salt Lake City, I hadn't driven on them before this weekend.

They work pretty well as long as you pay attention to the signs/lights/road, but they make me nervous about terrible drivers.

Diverging diamond.

Anytime I see a nifty interchange on a map, I go to this page and it straightens me out.

PittTheElder
Feb 13, 2012

:geno: Yes, it's like a lava lamp.

babyeatingpsychopath posted:

Anytime I see a nifty interchange on a map, I go to this page and it straightens me out.

That windmill. :godwinning:

Baronjutter
Dec 31, 2007

"Tiny Trains"

I didn't see that cool peanut shaped interchange on that list that Cichlidae learned me about a while ago and I thought was pretty cool/simple. It was like a long peanut-shaped circle over top of a highway. I guess it's a more compact version of a circle type.

Koesj
Aug 3, 2003

PittTheElder posted:

That windmill. :godwinning:

It's a funny looking design, but not that great compared to something like a turbine. A lot of German cloverleafs in the Rhein-Ruhr got (re)built with one or two windmill connectors to prevent weaving and speeds are still way lower than optimal on those ramps.

Last week we finally ditched the last remaining left-turning ramp of what was the only windmill interchange in the Netherlands here (Gmaps is out of date). Those tight curves just weren't cutting it anymore on the freeway interchange part, and the city-bound spur isn't as important volume-wise.

(1997, looking SE)


(late summer 2013, looking NW)

Varance
Oct 28, 2004

Ladies, hide your footwear!
Nap Ghost

Cocoa Crispies posted:

I took the top-level lane into town at about 10am last Friday, and it was amazing: no traffic, wide-open lanes, and I really really really wanted to take it at three-digit speeds.

It's kind of crazy how enormous it is though.
People regularly go triple-digits up there, as there's no law enforcement presence on the viaduct. I was up there this afternoon in a paratransit cutaway van, clipping along at 65-70MPH, getting passed by others going 15-20 MPH faster the entire way.

Baronjutter
Dec 31, 2007

"Tiny Trains"

http://video.wired.com/watch/bridge-replacement-in-18-hours-or-less
url says it all

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

Baronjutter posted:

I didn't see that cool peanut shaped interchange on that list that Cichlidae learned me about a while ago and I thought was pretty cool/simple. It was like a long peanut-shaped circle over top of a highway. I guess it's a more compact version of a circle type.

Dogbone interchange :)

Koesj posted:

It's a funny looking design, but not that great compared to something like a turbine. A lot of German cloverleafs in the Rhein-Ruhr got (re)built with one or two windmill connectors to prevent weaving and speeds are still way lower than optimal on those ramps.

Last week we finally ditched the last remaining left-turning ramp of what was the only windmill interchange in the Netherlands here (Gmaps is out of date). Those tight curves just weren't cutting it anymore on the freeway interchange part, and the city-bound spur isn't as important volume-wise.

(1997, looking SE)


(late summer 2013, looking NW)


That must've been a hell of a project to maintain traffic on. And speaking of which,


NYSDOT is doing that right now on I-84 just west of the state line. Weekend closures of the freeway to replace an entire structure - one weekend per half. I worked with SPMTs in Rhode Island, and those things are just plain amazing. Utah's been using so many of them that their accelerated construction costs are on par with traditional bridges.

Grundulum
Feb 28, 2006

Koesj posted:

It's a funny looking design, but not that great compared to something like a turbine. A lot of German cloverleafs in the Rhein-Ruhr got (re)built with one or two windmill connectors to prevent weaving and speeds are still way lower than optimal on those ramps.

Last week we finally ditched the last remaining left-turning ramp of what was the only windmill interchange in the Netherlands here (Gmaps is out of date). Those tight curves just weren't cutting it anymore on the freeway interchange part, and the city-bound spur isn't as important volume-wise.

(1997, looking SE)


(late summer 2013, looking NW)


I still see left-turning ramps in that lower picture. :confused: Besides the fact that it's now much harder to follow the various paths through the interchange, what's different/better?

Jaguars!
Jul 31, 2012


Grundulum posted:

I still see left-turning ramps in that lower picture. :confused: Besides the fact that it's now much harder to follow the various paths through the interchange, what's different/better?

Still under construction. If I've go this right, when the white concrete bridges are complete, the 'windmill' ramp & bridge running across the lower part of the picture will be removed.

Volmarias
Dec 31, 2002

EMAIL... THE INTERNET... SEARCH ENGINES...

Am I the only one that mentally made "OM NOM NOM" sounds watching the earthworks equipment chew up the old bridge?

smackfu
Jun 7, 2004

Seems like one negative of that bridge replacement is that the underpass is still closed for weeks while they build the new bridge .

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD
So, I've got a big ethical/moral dilemma with one of my projects. First, some background.

This concerns unsignalized left turn treatments. If you have enough cars turning left into a side street or driveway, you should put in a left turn lane. That decision is mostly made with the Harmelink charts, based on a bunch of (not very realistic) assumptions someone made in the 1960s. Much like the signal warrants, they're treated as commandments, even though they have little to back them.

I'm part of a committee to review a recent research report that analyzes left turn treatments on a benefit/cost basis. Essentially, it looks at the crash and delay reductions you'll get from a left turn lane vs. the cost of installing it. My job is to make a recommendation as to where we should go from here.

As you might expect, the old Harmelink charts are nowhere near what the B/C data would show. From a B/C standpoint, you should essentially have a left turn lane anywhere you can expect more than a couple left turns per hour; that is, at every non-residential driveway and every side street. This is due to the immense cost of traffic accidents: a single fatal accident results in a cost of over $8 million. A left turn lane reduces accidents by about half, so even at a relatively minor volume, putting in that lane saves a LOT of money. The delay savings are minimal when compared to safety and can effectively be discounted. At some of the locations where we're not putting left turn lanes in now, they'd probably save ten times their installation cost in accidents.

And that brings the dilemma: we don't have money to install left turn lanes. Sure, it amounts to robbing the citizens, but we can't raise gas taxes by a single cent. This isn't a problem specific to my committee (we frequently turn down jobs with high B/C ratios), but I am directly responsible for this case, and I want to do the right thing. Isn't it worth paying another :10bux: a year if you save the life of a family member, friend, or acquaintance?

For me, that's a pretty straightforward answer, but once you look at the implications, things get very tricky. When we have a traffic generator, anything from a little antique shop up to a Wal*Mart, its driveway will now require a left turn lane. The business must pay for this improvement, as they're the one causing the problem. For anything smaller than a big box store, it wouldn't have met the Harmelink warrants for a left turn lane, but it would definitely need one based on B/C. What do we do?
- If we continue our policy and accept the new warrants, then we'll hurt business, because dropping a million bucks on road improvements is a non-starter for a small company.
- If the state pays for improvements instead, we're not being fair to the businesses that already paid, we're using public money for private gain, and we would have to freeze all development since we don't have money for left turn lanes.
- If we stick with Harmelink warrants, we are knowingly acting against the public interest. As much as I'd love to put a sign up in the Walgreens parking lot saying 'this store will cost the citizens $200,000 per year because they were too cheap to drop $500,000 on a turn lane', I'm pretty sure that'd be considered vandalism.

That third option is probably what's going to happen, and honestly, I think it's the worst of the three. At least the other two save lives. Help me folks, what do I do?

Edit: If we're only building left turn lanes at a B/C of 10+, by the way, we're effectively saying that a life in Connecticut is worth a tenth what a life anywhere else is.

Silver Falcon
Dec 5, 2005

Two, three, four, five, six, seven, eight and barbecue your own drumsticks!

Would there be any way to get private businesses to kick in part of the cost of installing a left turn lane? I mean, even people not going to the business would benefit from having the turn lane, since it would mean they wouldn't have to wait behind some schmuck turning left on the one-lane road. (Super annoying!) Obviously the business benefits from it suddenly being easier to turn into.

Oh, and if there's more than one business using the driveway (like, a shopping center or something), then you could have a bunch of businesses kicking in for the cost!

Don't know if such a thing is even possible! Just a thought.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

Silver Falcon posted:

Would there be any way to get private businesses to kick in part of the cost of installing a left turn lane? I mean, even people not going to the business would benefit from having the turn lane, since it would mean they wouldn't have to wait behind some schmuck turning left on the one-lane road. (Super annoying!) Obviously the business benefits from it suddenly being easier to turn into.

Oh, and if there's more than one business using the driveway (like, a shopping center or something), then you could have a bunch of businesses kicking in for the cost!

Don't know if such a thing is even possible! Just a thought.

We don't have the money to even help out with the cost. We'd need to raise taxes to get any more.

As for businesses all cooperating, it can happen in very rare cases, but usually they just all blame each other and say, "my traffic taken alone doesn't warrant improvements, so why should I have to do anything?"

Baronjutter
Dec 31, 2007

"Tiny Trains"

Raise taxes, civilization costs money.

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Kaal
May 22, 2002

through thousands of posts in D&D over a decade, I now believe I know what I'm talking about. if I post forcefully and confidently, I can convince others that is true. no one sees through my facade.

Baronjutter posted:

Raise taxes, civilization costs money.

Pretty much this. Also, this problem is pretty much part and parcel with the problems of sprawl - so establish commercial districts and urban growth boundaries and halt annexations. Alternatively, start testifying at manslaughter trials that the business' refusal to install necessary traffic improvements constitutes partial negligence.

Kaal fucked around with this message at 23:51 on Oct 22, 2013

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