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Any Ideas for Tackling Wilmington, NC's Worsening Traffic?

Started by architect77, November 08, 2021, 03:50:47 PM

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architect77

Even during the Winter months, Wilmington's traffic is bad, and it moves slower on the main throughfares than in Atlanta.

All of the road enthusiasts here ought to be able to offer meaningful and realistic proposals for Wilmington's present and future mobility.

It's going to require some outside-the-box thinking.

All I know is that now you spend a lot of daily minutes to go anywhere. The main roads are packed and the major intersections take 5 minutes to get through.

Could Jersey jughandles be added to remove the left-turn phases?

Could we dig trenches for left turns to go under intersections?

Is there room for some sort of parallel roads to be added for express purposes?

Can a diverging diamond concept be applied to a regular intersection and not just at freeway junctions?

I don't think freeways will help since the traffic is mostly local in nature, but something needs to be done now. I find myself loathing driving when I'm there, and that's in the off season.





fillup420

I was in Wilmington/Hampstead recently and I concur, the traffic there is dreadful.

No matter what else is done to mitigate it, less traffic lights must be a part of it. The drive into Wilmington on US 17 south is just light after light after light. Its terrible, traffic backs up through lights even at 1pm. It also doesnt help that the average driver aggression level is way higher than what Im used to.

froggie

A big complicating factor is the style of development that is allowed (especially in the South in my experience) with multiple private driveway/access points along the arterial road and an acute lack of frontage roads.  It's been very well documented that as the number of access points per mile increases, both crashes and congestion increase.  There is no reasonable way to fix this, and if NC's experience with the Map Act fiasco is any indication, reserving the right-of-way for such would be both costly and litigious.

Quote from: architect77Can a diverging diamond concept be applied to a regular intersection and not just at freeway junctions?

A similar concept to what you're thinking that exists (but is still new) is the Continuous Flow Intersection (also called the Displaced Left Turn).  In this scenario, left turns come off the mainline BEFORE the intersection, then at the cross road, left turning traffic turns left at the same time as the green for through traffic.  The only existing example I could find in your area is at GA 400/53 in Dawson County.

RoadPelican

There is one intersection in Charlotte with displaced left turns.  State Route 16 and Mt. Holly-Huntersville Road.

SkyPesos

Quote from: froggie on November 08, 2021, 04:20:18 PM
A big complicating factor is the style of development that is allowed (especially in the South in my experience) with multiple private driveway/access points along the arterial road and an acute lack of frontage roads.  It's been very well documented that as the number of access points per mile increases, both crashes and congestion increase.
Pretty much why I dislike (most) stroads.

RoadPelican

Better planning for future growth:

1) I-40 should have been extended all the way to Carolina Beach.

2) The US 17 freeway coming from Brunswick County should have been extended along (Dawson/Wooster Street, Oleander Drive, and Military Cutoff Road)

These two freeways would give Wilmington a good cross town freeway base that is SORELY lacking in the city today.

There are a few bright spots in the future though:

Military Cutoff Extension is due to be complete in 2023.  Should help traffic in Porter's Neck/Ogden area (Market Street)

Other projects funded in 2020-2029 STIP

MLK Parkway (traffic lights to be replaced with interchanges) (Kerr Avenue, North College Road and Market Street)

Eastwood Road and Military Cutoff Road (traffic light converted to Interchange)

Independence Blvd extension from Randall Parkway to MLK Parkway (includes interchange with Market Street)

College Road (upgrade arterial to freeway) Gordon Road to New Centre Drive

College Road & Carolina Beach Road (traffic light converted to interchange)

US 421 & 3rd Street (near Isabel Holmes Bridge) upgrade to interchange

TWO BIG NEEDS NOT FUNDED in STIP:

A replacement or new bridge for the Cape Fear River into Downtown Wilmington.

The intersection of College Road and Oleander Drive keeps getting pushed back in the STIP schedule.  This BADLY needs an interchange but it's going to be  VERY expensive with all the buildings in the area.



RoadPelican

Quote from: froggie on November 08, 2021, 04:20:18 PM
A big complicating factor is the style of development that is allowed (especially in the South in my experience) with multiple private driveway/access points along the arterial road and an acute lack of frontage roads.  It's been very well documented that as the number of access points per mile increases, both crashes and congestion increase.  There is no reasonable way to fix this, and if NC's experience with the Map Act fiasco is any indication, reserving the right-of-way for such would be both costly and litigious.

This is a big reason why Wilmington (and Greenville) is at the top or near the top for highest accident rate in the state year after year.  Too many roads with a center turn lane instead of a median to restrict left turns and too many driveways in a tiny area.  Although they are building a median along Market Street now, but Carolina Beach Road from Independence Blvd to downtown as well as College Road from Wilshire Blvd to Shipyard Blvd and some of Oleander Drive are dangerous to drive because too many think they can turn left across multiple lanes of traffic.

Tom958

Quote from: RoadPelican on November 08, 2021, 06:55:05 PM
There are a few bright spots in the future though:

Eight new interchanges replacing intersections on many of the area's congested arterials, almost all of which are lined with commercial development. I don't know of any place in the US where that's been done before. OK, there are a good many arterial interchanges in NC, but most are along purpose-built expressways/parkways like Wendover Boulevard in Greensboro and Capital Boulevard and Wade Avenue in Raleigh. I'd argue that what you're talking about here is new and untried. It'll be interesting to see how it pans out.

There's only one such interchange in Wilmington now, and it was clearly built in the fifties, long before the roads it serves were lined with development. Perhaps it still captures the imaginations of Wilmingtonians.

https://ncdot.maps.arcgis.com/home/webmap/viewer.html?webmap=cb02f4f828974670ad01bb83be91b18c

Tom958

I'm fascinated enough by this to make my own map. The red lines are the Independence Boulevard and Military Cutoff Road extensions, and the green line is the freeway conversion of College Road. The blue diamonds are the proposed interchange sites. The blue arrows point south along College Road and Carolina Beach Road; there's to be another interchange where they intersect. From my readings, I've learned that most or all will be SPUIs or tight urban diamonds, not the jughandles that one might expect. I wish I knew which of the intersecting routes have priority. 

I reiterate: While NC has plenty of arterial interchanges, I don't know of any other place in the US with so many interchanges retrofitted to arterials that are already lined with development, especially in such a small area. AFAIK, this is something new and... exciting?


RoadPelican

Good map, the interchange site just north of Downtown is actually across the river.

Tom958

Quote from: RoadPelican on November 13, 2021, 08:38:02 PM
Good map, the interchange site just north of Downtown is actually across the river.

Yes, how silly of me. Your post clearly said US 421.

kendallhart808

I live in Wilmington but am originally from Raleigh - and I certainly have some ideas because I concur, the traffic is irritating.

The lights need to be longer at many of the intersections. College/Oleander from Oleander and Market/Eastwood/MLK Parkway from Eastwood come to mind. College and Market have lights that are timed wayyyy longer than Oleander/Eastwood and unless it's 8pm, you just can't get through in one cycle. Especially left turns. I can sit through three light cycles at Market on Eastwood before getting through and won't be backed up *that* far.

I also think eliminating driveways and cross roads on College between Wilshire Blvd and Oleander would help. Theres really no need to have anything beyond Wilshire, Wrightsville, Kerr, and Oleander intersections, and even that is a lot. Timing those lights would work wonders.

Northbound College Road would benefit from the third lane that the southbound lanes have. Albeit this would definitely impact the businesses, especially north of Oleander.

College would also benefit from a six-lane setup all the way to Carolina Beach Road/US 421. US 421/Carolina Beach Road would benefit from a six-lane setup from College to Burnett Blvd/Front Street. Same with Market but the driveways also need to be consolidated.

RIGHT TURN LANES - they would be so beneficial at moving traffic around. College/Oleander, Eastwood/Military Cutoff, and New Centre/Market come to mind. New Centre needs two thru lanes going north at Market.

Of course, I also think the upcoming and under construction projects will help. I have my doubts that extending the I-40 freeway south to New Centre will do anything but create a mess at New Centre but we shall see. It'll be interesting to see if I-40 gets extended to US 17 Business. The drawings make it look like it could be built to Interstate standards.

DJStephens

Quote from: Tom958 on November 13, 2021, 08:02:30 PM
I reiterate: While NC has plenty of arterial interchanges, I don't know of any other place in the US with so many interchanges retrofitted to arterials that are already lined with development, especially in such a small area. AFAIK, this is something new and... exciting. 

US - 19 in the Tampa / St. Petersburg metro, perhaps, although am sure Wilmington is certainly more confined due to it's geography and growth patterns.   

Tom958

Quote from: DJStephens on November 26, 2021, 11:31:12 AMUS - 19 in the Tampa / St. Petersburg metro, perhaps, although am sure Wilmington is certainly more confined due to it's geography and growth patterns.

Yes, that's probably the best example. There, though, it's an entire corridor being systematically upgraded. the interchanges in Wilmington seem much more sporadic in their placement. I should've mentioned that as the most unusual aspect of Wilmington's plan, but I didn't.

tolbs17

I used to be obsessed with improving intersections and making them highways, but Greenville, North Carolina's traffic problems are not too far behind.

Urban freeways and interchanges are more expensive to build compared to rural designs.

sprjus4

Quote from: Tom958 on November 26, 2021, 12:07:49 PM
Quote from: DJStephens on November 26, 2021, 11:31:12 AMUS - 19 in the Tampa / St. Petersburg metro, perhaps, although am sure Wilmington is certainly more confined due to it's geography and growth patterns.

Yes, that's probably the best example. There, though, it's an entire corridor being systematically upgraded. the interchanges in Wilmington seem much more sporadic in their placement. I should've mentioned that as the most unusual aspect of Wilmington's plan, but I didn't.
Isn't US-19 in that area built to full freeway standards - sort of Texas style with continuous frontage roads and U-turns - for a significant distance, though?

Tom958

Quote from: sprjus4 on November 26, 2021, 02:09:22 PM
Quote from: Tom958 on November 26, 2021, 12:07:49 PM
Quote from: DJStephens on November 26, 2021, 11:31:12 AMUS - 19 in the Tampa / St. Petersburg metro, perhaps, although am sure Wilmington is certainly more confined due to it's geography and growth patterns.

Yes, that's probably the best example. There, though, it's an entire corridor being systematically upgraded. the interchanges in Wilmington seem much more sporadic in their placement. I should've mentioned that as the most unusual aspect of Wilmington's plan, but I didn't.
Isn't US-19 in that area built to full freeway standards - sort of Texas style with continuous frontage roads and U-turns - for a significant distance, though?

Yes, it is. 12.2 miles so far, to be exact. It's far bigger in scale than what Wilmington's planning, but also different in character. I appreciate your ability to see the difference despite my own poorly-worded initial characterization. This may actually be something novel.

architect77

I think that just eliminating the protected left phase at some big intersections would really help.

The land is flat and there is enough available to build Jersey jughandles so that you'd make a big right loop onto the perpendicular street instead of a protected left.

In East Brunswick, NJ the main thoroughfare has no left turns and it moves a tremendous amount of cars through intersections that have a simple signal phase of stop/go.

jdunlop

Quote from: architect77 on November 30, 2021, 02:06:19 PM
I think that just eliminating the protected left phase at some big intersections would really help.

The land is flat and there is enough available to build Jersey jughandles so that you'd make a big right loop onto the perpendicular street instead of a protected left.

In East Brunswick, NJ the main thoroughfare has no left turns and it moves a tremendous amount of cars through intersections that have a simple signal phase of stop/go.

That's the concept behind the Reduced Conflict Intersection (RCI. aka superstreet, RCUT, J-Turn.). Also, the Michigan Left does the same thing.

The difference is the the Jersey Jughandle redirects the Main Street left (as you mentioned) and turns it into a side street movement.  I see the negatives compared to the RCI as: the side street signal requires both directions of the Main Street to stop at the same time, making coordination tougher, and turning volume on the side streets may require additional signal phases.  Trade offs include deciding if you want to need more R/W at the intersection, or at the U-Turn bulbs (the U-turn bulbs are more flexible in terms of location, and can usually be fit in easier.). In NJ, the Corridor R/W is typically narrower than the RCI/superstreet.

For NC, most cities have developed in a hub and spoke pattern.  That means most of the side street traffic gets on/off the Main Street rather than going through.  The RCI, with the direct lefts, makes that easier in many cases.

As a retrofit, the RCI is typically easier, as most of the corners at intersections are already built out.  I don't think you're going to find many jughandle corridors in NC (and certainly not as long as this NJ guy has a say!   :-P )

architect77

Quote from: jdunlop on November 30, 2021, 03:38:33 PM
Quote from: architect77 on November 30, 2021, 02:06:19 PM
I think that just eliminating the protected left phase at some big intersections would really help.

The land is flat and there is enough available to build Jersey jughandles so that you'd make a big right loop onto the perpendicular street instead of a protected left.

In East Brunswick, NJ the main thoroughfare has no left turns and it moves a tremendous amount of cars through intersections that have a simple signal phase of stop/go.

That's the concept behind the Reduced Conflict Intersection (RCI. aka superstreet, RCUT, J-Turn.). Also, the Michigan Left does the same thing.

The difference is the the Jersey Jughandle redirects the Main Street left (as you mentioned) and turns it into a side street movement.  I see the negatives compared to the RCI as: the side street signal requires both directions of the Main Street to stop at the same time, making coordination tougher, and turning volume on the side streets may require additional signal phases.  Trade offs include deciding if you want to need more R/W at the intersection, or at the U-Turn bulbs (the U-turn bulbs are more flexible in terms of location, and can usually be fit in easier.). In NJ, the Corridor R/W is typically narrower than the RCI/superstreet.

For NC, most cities have developed in a hub and spoke pattern.  That means most of the side street traffic gets on/off the Main Street rather than going through.  The RCI, with the direct lefts, makes that easier in many cases.

As a retrofit, the RCI is typically easier, as most of the corners at intersections are already built out.  I don't think you're going to find many jughandle corridors in NC (and certainly not as long as this NJ guy has a say!   :-P )

I'm open to the superstreet and Michigan left for wilmington. The NC superstreet seems overly complicated sometimes though. the intersections deny the minor road from going straight thru, and in Wilmington there seems to be 4 big intersections that form a square on a map that I cant ever distinguish from one another. They are too busy to deny one from going straight thru so perhaps the Michigan left is the simplist solution.

Freeways aren't needed in my opinion, but maybe an express lane at separated grade level through these time-consuming intersections could also work.

sprjus4

^ Ideally, I-40 would continue as an urban interstate highway down US-117, NC-132, and US-421 down towards Carolina Beach, though obviously right of way constraints make that an unrealistic concept nowadays.



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