New Jersey Turnpike

[Beltway]

What's the AADT on I-295 vs. NJTP?

The best public source I've found thus far:
https://dspace.njstatelib.org/xmlui/bitstream/handle/10929/23355/f4912008d.pdf?sequence=1&isAllowed=y
page 16 has outdated AADTs but at least 2006 is getting in the ballpark. (Figure 1% growth per year as a rough guideline for NJ, and see what you think from there)

46,000 to 49,000 AADT between Exits 1 and 3  -- close to 6-lane warrants
58,000 AADT between Exits 3 and 4                 -- meets 6-lane warrants

Like you said that was 2006.

1.01 to the 14th power is about a 14.9% increase.

[sprjus4]

46,000 to 49,000 AADT between Exits 1 and 3  -- close to 6-lane warrants

Considering the peak travel period volumes would be higher, along with the fact overall AADT levels are likely higher today in general, this stretch certainly warrants 6-lanes throughout.

[Beltway]

46,000 to 49,000 AADT between Exits 1 and 3  -- close to 6-lane warrants

Considering the peak travel period volumes would be higher, along with the fact overall AADT levels are likely higher today in general, this stretch certainly warrants 6-lanes throughout.

Adding 15% (1.0% increase per year is about the typical average for rural Interstates) would yield 52,900 to 56,350.

Needs 6 lanes.

[sprjus4]

https://www.njta.com/media/4280/os-2019a.pdf

PDF Page 231

2017 Traffic Volumes

Exits 1 to 2 - 48,800 - 12.4% truck
Exits 2 to 3 - 53,400 - 12.4% truck
Exits 3 to 4 - 63,300 - 12.3% truck

Warrants 6-lanes, especially when you consider peak travel period volumes that could easily bring these numbers to 70,000 or greater.

Actually, the report indicates between Exits 1 and 2, July volumes were 21% higher than the average month, meaning Exits 1 and 2 see up to 59,048 AADT during peak season, and this doesn't even factor weekends alone will see even more traffic than during the week. Using this 21% figure on the other exits too, assuming it's similar...

July Traffic Volumes 2017 (AADT x 1.21) -

Exits 1 to 2 - 59,048
Exits 2 to 3 - 64,614
Exits 3 to 4 - 76,593

Most certainly warrants 6-lanes throughout.

As for the rest of the Turnpike south of Exit 9...

Exits 4 to 5 - 84,000 - 12.3% truck
Exits 5 to 6 (I-95) - 89,900 - 12.2% truck

Should eventually be expanded to 8-lanes, especially as volumes will continue to rise.

Exits 6 (I-95) to 7 - 119,000 - 13.1% truck
Exits 7 to 7A - 132,300 - 14.1% truck
Exits 7A to 8 - 150,200 - 15.1% truck
Exits 8 to 8A - 155,600 - 14.7% truck
Exits 8A to 9 - 175,700 - 14.4% truck

The recent 12-lane expansion should be able to handle traffic volumes south of Exit 9 for years, if not decades, to come.

[Beltway]

Should eventually be expanded to 8-lanes, especially as volumes will continue to rise.

NJTA doesn't seem to like 8-lane widening, my observations Exits 6 to 9 back in the 1970s was that would have been a good solution to the very busy 6-lane section.  They waited almost 40 years to add parallel 6-lane roadways, which -are- needed today.

Exits 6 (I-95) to 7 - 119,000 - 13.1% truck
Exits 7 to 7A - 132,300 - 14.1% truck
Exits 7A to 8 - 150,200 - 15.1% truck
Exits 8 to 8A - 155,600 - 14.7% truck
Exits 8A to 9 - 175,700 - 14.4% truck
The recent 12-lane expansion should be able to handle traffic volumes south of Exit 9 for years, if not decades, to come.

Given the proximity to major metros, I would suggest a 2% average growth per year.

In 10 years that range will be 183,100 to 213,300 for the section on single routing, Exits 7A to 9.  Pushing the limits of even 12 lanes.

Those are very high truck volumes, ranging from about 15,000 to 24,000.  That is enough to well-fill a 4-lane truck-only freeway.

[sprjus4]

Given the proximity to major metros, I would suggest a 2% average growth per year.

In 10 years that range will be 183,100 to 213,300 for the section on single routing, Exits 7A to 9.  Pushing the limits of even 12 lanes.

Comparing 2013 volumes to 2017...

Exits 6 to 7 - 99,600 / 119,000 (6.3% growth per year)
Exits 7 to 7A - 109,300 / 132,300 (7% growth per year)
Exits 7A to 8 - 120,700 / 150,200 (8.1% growth per year)
Exits 8 to 8A - 123,500 / 155,600 (8.6% growth per year)
Exits 8A to 9 - 145,200 / 175,700 (7% growth per year)

Over a 3 year period, this segment of the NJTP saw an increase of 6.3% to 8.6% growth per year. Not to mention, both the 2013 and 2017 volumes come before the I-95 / Pennsylvania Turnpike interchange / connector was completed in 2018, which would have likely brought additional volumes onto the Turnpike north of Exit 6.

[Beltway]

The widening may have enabled a spike between 2013 and 2017.

[sprjus4]

The widening may have enabled a spike between 2013 and 2017.

Indeed, and would make more sense as those numbers show a -significant- increase that maintained over many future years spikes the numbers beyond reason.

[Beltway]

The widening may have enabled a spike between 2013 and 2017.

Indeed, and would make more sense as those numbers show a -significant- increase that maintained over many future years spikes the numbers beyond reason.

Yeah, normally that would seem to be very high per year growth rates.

[RobbieL2415]

Any word on if the inner carriageways will be closed?

[jeffandnicole]

Should eventually be expanded to 8-lanes, especially as volumes will continue to rise.

NJTA doesn't seem to like 8-lane widening, my observations Exits 6 to 9 back in the 1970s was that would have been a good solution to the very busy 6-lane section.  They waited almost 40 years to add parallel 6-lane roadways, which -are- needed today.

Supposedly the Turnpike did consider a 10 lane, 5×5 widening of Turnpike between Exits 6 and 8A, but ultimately didn't pursue it.

Any word on if the inner carriageways will be closed?

Why? There's no reason to close then except for overnight work purposes.

[Alps]

Just a side note: AADT is only used in an annual context. You would want AMDT when talking about July. Other useful measures include AAWDT (weekdays) or AADTT (trucks).

[bluecountry]

What's the AADT on I-295 vs. NJTP?

The best public source I've found thus far:
https://dspace.njstatelib.org/xmlui/bitstream/handle/10929/23355/f4912008d.pdf?sequence=1&isAllowed=y
page 16 has outdated AADTs but at least 2006 is getting in the ballpark. (Figure 1% growth per year as a rough guideline for NJ, and see what you think from there)

46,000 to 49,000 AADT between Exits 1 and 3  -- close to 6-lane warrants
58,000 AADT between Exits 3 and 4                 -- meets 6-lane warrants

Like you said that was 2006.

1.01 to the 14th power is about a 14.9% increase.

1.  How do you figure that meets the threshold for 6 lanes?
2.  Regardless, it still should be a lower priority behind widening from exit 4 to 6 to 8 lanes; and from 18W to 6 lanes.

[sprjus4]

1.  How do you figure that meets the threshold for 6 lanes?

Those are high volumes for a rural 4-lane freeway, notably one that carries increased volumes during peak travel periods. It warrants 6-lanes.

[Alps]

1.  How do you figure that meets the threshold for 6 lanes?

Those are high volumes for a rural 4-lane freeway, notably one that carries increased volumes during peak travel periods. It warrants 6-lanes.

2017 Traffic Volumes

Exits 1 to 2 - 48,800 - 12.4% truck
Exits 2 to 3 - 53,400 - 12.4% truck
Exits 3 to 4 - 63,300 - 12.3% truck


was stated above. Other things that will help you:
* What is the directionality of traffic - typically 51% to 55% in the peak direction
* What is the truck factor - HCM would say 1.5%, but could be higher depending on actual truck dynamics
* What percent of AADT is peak hour - typical range 8% rural to 12% urban traffic
* What growth per year and what is your construction horizon - we've been saying 1% but it could be under 1% in the county and over 1% on the Turnpike, or vice versa

I don't have an HCM in front of me, but Google says at a free-flow speed of 70 mph, 1,770 passenger cars/hour/lane is the LOS C/D threshold (3,540 for a 2-lane highway), and you're supposed to keep freeways at LOS C or better.

[Steve D]

[/quote]
1.  How do you figure that meets the threshold for 6 lanes?
2.  Regardless, it still should be a lower priority behind widening from exit 4 to 6 to 8 lanes; and from 18W to 6 lanes.
[/quote]


How often is traffic an issue between 4 and 6?  It seems notably absent from the 10 year capital plan.

Concerning the proposed crossovers between 8a and 9, I assume that will involve multiple ramps since the budget is around $270 million, but I'm trying to picture how that would work.

[sprjus4]

How often is traffic an issue between 4 and 6?  It seems notably absent from the 10 year capital plan.

While it would ideally eventually get 8-lane widening based on volumes, traffic is more tolerable and has less congestion issues in that area vs. south of Exit 4, where 6-lane widening is needed and programmed down to Exit 1.

Exit 4 to 6 is less of a priority than Exit 1 to 4. After the latter is completed, then the former would be the next step.

[jeffandnicole]

1.  How do you figure that meets the threshold for 6 lanes?
2.  Regardless, it still should be a lower priority behind widening from exit 4 to 6 to 8 lanes; and from 18W to 6 lanes.

How often is traffic an issue between 4 and 6?  It seems notably absent from the 10 year capital plan.

Generally it's ok.  The biggest issue appears to be the narrowing from 3 lanes to 2 at Interchange 4 on the Southbound side.  You'll find 3+ mile backups approaching Exit 4 during busier travel periods.  There's 3 real good spots for the Troopers to hide out in that stretch, which probably reflects that speeds are often quite high in this area of the Turnpike: NB in front of the service area.  SB just after Interchange 5 and the maintenance/State Police overpass approaching Interchange 4.

Otherwise, traffic moves pretty good.  I'll say I'm impressed at how well traffic merges down from 6 lanes to 3 below Interchange 6, although I still feel they should've gone another mile or so south where there's a good 1 mile plus of straightaway on a slight hill where there would've been wonderful sightlines and views of the merge would've been very photogenic.

And regarding traffic counts, I would be more interested about travel speeds than volumes on the Turnpike.  NJDOT releases them for specific areas on their road and highway system, and isn't shy about revealing measured speeds.  A few locations have 85th percentile speeds slightly over 80 mph (piss on that, VA!).

[sprjus4]

https://www.nj.com/data/2018/08/should_the_speed_limit_on_njs_highways_be_higher_we_used_a_radar_gun_to_find_the_answer.html

Here's an interesting article.

I-287, Route 55, New Jersey Turnpike, I-295, and the Atlantic City Expressway, with 55 mph or 65 mph speed limits, all have 85th percentile speeds at or above 77 mph, with the New Jersey Turnpike in Chesterfield having an 85th percentile speed of 82 mph, just north of I-95 enters where the Turnpike is 12 lanes, wide open.

[Don'tKnowYet]

The maximum speed limit in NJ is set by the Legislature at 65.  I would bet that the Turnpike in thr south would raise it if it could.

[sprjus4]

The maximum speed limit in NJ is set by the Legislature at 65.  I would bet that the Turnpike in thr south would raise it if it could.

The legislation needs to be changed then to allow at least 70 mph on rural freeways. Additionally, if they wanted to strictly increase the Turnpike but no other road, language could be included to limit a 70 or 75 mph speed limit to solely the New Jersey Turnpike, and could go as far as to listing specific segments.

[Beltway]

The maximum speed limit in NJ is set by the Legislature at 65.  I would bet that the Turnpike in thr south would raise it if it could.

The maximum speed limit in NJ for 2-lane highways is only 50 mph.

Or are there any that are higher?

[sprjus4]

The maximum speed limit in NJ is set by the Legislature at 65.  I would bet that the Turnpike in thr south would raise it if it could.

The maximum speed limit in NJ for 2-lane highways is only 50 mph.

Or are there any that are higher?

It seems rare, but some are posted at 55 mph.

NJ-72 - https://www.google.com/maps/@39.8485306,-74.4936581,3a,38.5y,304.49h,86.68t/data=!3m6!1e1!3m4!1sH6U8yCQpIYkA2-Hj7oEyKA!2e0!7i13312!8i6656!5m1!1e1
NJ-70 - https://www.google.com/maps/@39.8997913,-74.5934135,3a,37.5y,76.26h,87.67t/data=!3m6!1e1!3m4!1sshGAsX76ktspGnQgc7s42g!2e0!7i16384!8i8192!5m1!1e1

What is the speed limit in NJ?
New Jersey law sets top speed limits for any given road, street, highway, or freeway. The speed limit, unless otherwise posted, is 25 mph in school zones, business, or residential districts; 35 mph in certain low density business and residential districts; 50 mph on all other roadways; 55 mph on certain state highways (as posted) and all interstates; and 65 mph on certain state highways (as posted).

https://nj.gov/faqs/drive/

[Beltway]

The maximum speed limit in NJ for 2-lane highways is only 50 mph.  Or are there any that are higher?

It seems rare, but some are posted at 55 mph.
NJ-72 -
NJ-70 -

Like Maryland and Delaware. 

Nearly all have a maximum of 50 mph except for a couple that are 55 mph.

[sprjus4]

Like Maryland and Delaware. 

Nearly all have a maximum of 50 mph except for a couple that are 55 mph.

And given the high quality design of many of the roadways, they could easily handle up to 65 mph or greater, though being an Eastern Seaboard state, would never happen. I'd be curious to see the 85th percentile speeds on many of those rural two-lane segments in undeveloped, wide-open areas.

The highest posted speed limit on two-lane roads on the Eastern Seaboard IIRC is in Florida with 60 mph.

Texas has the highest posted in the country, with hundreds of two-lane mileage posted at 70 - 75 mph. Very little to no incentive to exceed the speed limit, and people rarely exceed 5 over. My experience debunks the theory that the higher you post a limit people will just speed more. If you set an appropriate limit that matches the design of the road, most people will comply, certainly within a 5 mph range.