Rural Freeways That Will Never Need 6 Lanes

[jakeroot]

Every current rural freeway. The decision to widen a freeway is always a value judgment and never a need

That's just not accurate.

Every current rural freeway. The decision to widen a freeway is always a value judgment and never a need.

I'm trying to imagine I-95 between Philly and Baltimore with only four lanes. Certainly more of a need than a value judgment, if you ask me.

I'm trying to imagine every single freeway in the U.S. shrinking to four lanes after it leaves an urban area. There's many stretches with up to 8-lanes for miles through rural areas, and there's good reason for that.

I think you guys might be over-reading his comment. He's saying that widening is a value judgement, which virtually all widening jobs are. Agencies evaluate the economic and safety benefits to widening a road; as long as the math works out, the road gets widened. For every widened stretch of rural interstate, this math has worked out.

The difference between "value" and "need" is, to many, semantics, since there would seem to be value proposition if there was also a need. But if an agency found there to be no economic benefit to widening a road (too expensive relative to benefits), just because it was busy (and giving the appearance of necessity) doesn't necessarily make widening good value.

[cl94]

I-87 (the real one) north of Northway Exit 23. It's the least-traveled extended section of freeway in New York. None of it tops 20,000 and there is a section in Essex County (30-31) with an AADT around 6K.

I-88 (eastern) is another candidate. Other than climbing lanes in a few places, none of that will ever need more than 4 lanes. Most of that has an AADT under 20,000 with the Oneonta-Cobleskill section being under 10,000.

I'm inclined to say I-81 north of I-781, too. 781 has a higher AADT than the northern bit of 81 (which bottoms out under 5K on Wellesley Island). However, this MAY change if a US 11 bypass is ever built and said bypass ties into 81.

OP mentioned I-95 north of Bangor and I agree wholeheartedly. When I did that stretch NB on a summer morning, I saw NO other NB cars (or animals). It was "set cruise to 78 and watch for moose".

The only other stretch I have been on with traffic nearly that low (but NOT that low) was the aforementioned I-70 between US 89 and US 6 (across the San Rafael Swell), although climbing lanes would have been nice in a couple places due to people who don't know how to accelerate on hills. I-70 east of US 6 I might be able to see an eventual 6-lane on if UDOT ever gets their head out of their ass and widens the US 6 corridor.

[webny99]

Every current rural freeway. The decision to widen a freeway is always a value judgment and never a need

That's just not accurate.

Every current rural freeway. The decision to widen a freeway is always a value judgment and never a need.

I'm trying to imagine I-95 between Philly and Baltimore with only four lanes. Certainly more of a need than a value judgment, if you ask me.

I'm trying to imagine every single freeway in the U.S. shrinking to four lanes after it leaves an urban area. There's many stretches with up to 8-lanes for miles through rural areas, and there's good reason for that.

I think you guys might be over-reading his comment. He's saying that widening is a value judgement, which virtually all widening jobs are. Agencies evaluate the economic and safety benefits to widening a road; as long as the math works out, the road gets widened. For every widened stretch of rural interstate, this math has worked out.

The difference between "value" and "need" is, to many, semantics, since there would seem to be value proposition if there was also a need. But if an agency found there to be no economic benefit to widening a road (too expensive relative to benefits), just because it was busy (and giving the appearance of necessity) doesn't necessarily make widening good value.

What other criteria are there, besides "busy" and variants thereof?

IMO, to the extent "need" and "value judgment" have different meanings, "need" is more applicable in most, if not all, cases of widening.

[jakeroot]

What other criteria are there, besides "busy" and variants thereof?

IMO, to the extent "need" and "value judgment" have different meanings, "need" is more applicable in most, if not all, cases of widening.

It's mostly a cost-to-benefit ratio exercise. This is more often a problem in urban areas where ROW and/or reconstruction can be too expensive relative to the economic benefit of an extra lane, or in rural areas that are geographically challenging to build through (increasing the cost). Adding lanes is not always a simple "add asphalt" exercise. It's entirely possible that in curvy areas, an additional outside lane would be too sharp, necessitating an entire rebuild of the freeway. With that knowledge, the responsible agency may be waiting for a certain "tipping point" where they're a bit happier to dump money into the road.

For example, if an agency wanted to add an auxiliary lane between two exits, it would be much easier and cheaper to do so if the two exits were on a relatively flat and straight alignment with one another. But if the entire carriageway needed rebuilding to add the lane (due to a curve or hill, or something else), it's unlikely the agency would hop to it until it was really necessary.

This is a problem in the Seattle area, where our freeways run in very tight ROW's with some rather tight corners. Modifying freeways is a very expensive process, and thanks to that, WSDOT's "tipping point" for adding lanes is much higher than other regions. As a result, you see the state and local councils pushing alternative modes of transport to reduce the need for widening.

[webny99]

What other criteria are there, besides "busy" and variants thereof?
IMO, to the extent "need" and "value judgment" have different meanings, "need" is more applicable in most, if not all, cases of widening.

It's mostly a cost-to-benefit ratio exercise. This is more often a problem in urban areas where ROW and/or reconstruction can be too expensive relative to the economic benefit of an extra lane, or in rural areas that are geographically challenging to build through (increasing the cost). Adding lanes is not always a simple "add asphalt" exercise. It's entirely possible that in curvy areas, an additional outside lane would be too sharp, necessitating an entire rebuild of the freeway. With that knowledge, the responsible agency may be waiting for a certain "tipping point" where they're a bit happier to dump money into the road.

For example, if an agency wanted to add an auxiliary lane between two exits, it would be much easier and cheaper to do so if the two exits were on a relatively flat and straight alignment with one another. But if the entire carriageway needed rebuilding to add the lane (due to a curve or hill, or something else), it's unlikely the agency would hop to it until it was really necessary.

Yeah, I actually agree with all of that. I just think such is mostly applicable in urban and suburban areas, where ROW is likely to be limited, freeways may have a lot of pre-existing curvature, and so forth.

Aside from mountain passes or areas with otherwise extreme terrain, I would expect the tipping point to be lower - a lot lower - relative to average in rural areas. That is part of the reason I specific rural in my original thread; most rural widenings are not totally fictional/theoretical like a downtown freeway widening would be. Congestion is to be expected in or near large cities. When you start getting recurring slowdowns and traffic moving below speed in exurban and rural areas, though, it really isn't even a question of whether a widening should occur.

[Beltway]

For example, if an agency wanted to add an auxiliary lane between two exits, it would be much easier and cheaper to do so if the two exits were on a relatively flat and straight alignment with one another. But if the entire carriageway needed rebuilding to add the lane (due to a curve or hill, or something else), it's unlikely the agency would hop to it until it was really necessary.

Yeah, I actually agree with all of that. I just think such is mostly applicable in urban and suburban areas, where ROW is likely to be limited, freeways may have a lot of pre-existing curvature, and so forth.

Many of the original Interstate highways were built with open grass medians that are wide enough so that at least one lane and shoulder each way can be added without rebuilding the rest of the roadways.

[froggie]

^ That's generally the case, but depending on topography you still may need additional right-of-way even with an open median for retention basins to handle the additional runoff.

[jakeroot]

Aside from mountain passes or areas with otherwise extreme terrain, I would expect the tipping point to be lower - a lot lower - relative to average in rural areas. That is part of the reason I specific rural in my original thread; most rural widenings are not totally fictional/theoretical like a downtown freeway widening would be. Congestion is to be expected in or near large cities. When you start getting recurring slowdowns and traffic moving below speed in exurban and rural areas, though, it really isn't even a question of whether a widening should occur.

Makes sense to me. To be clear, in rural areas, the value of an added lane would be much higher since it's generally much cheaper to add it. But if, say, 12 cars use a particular stretch each day, obviously the state would never see an economic benefit from six-laning that stretch. Even if widening were cheap, there'd be very little value in it. It still all boils down to "value" but the factors within that value measurement are generally both less numerous and less restrictive in rural areas. Minus places like mountain passes, where tunnels and bridges (plus tight corners) are more common.

[Beltway]

^ That's generally the case, but depending on topography you still may need additional right-of-way even with an open median for retention basins to handle the additional runoff.

True, but it is not like the postulated massive expansion that inspired my comments.

[ftballfan]

US-31 north of North Muskegon
US-131 north of Cedar Springs
I-75 north of Standish

[swhuck]

Any unbuilt portion of I-14 

[RobbieL2415]

How about I-75 in Alligator Alley?

[vdeane]

How about I-75 in Alligator Alley?

There's actually a surprising amount of traffic considering that the area it passes though has practically no development, and Florida is a growing state.  Whether it's even possible to widen it considering it goes through the Everglades is another matter.

[Flint1979]

How about I-75 in Alligator Alley?

There's actually a surprising amount of traffic considering that the area it passes though has practically no development, and Florida is a growing state.  Whether it's even possible to widen it considering it goes through the Everglades is another matter.

It's probably possible. The right of way and median are pretty wide all the way through and it's already four lanes but with how many people live in Miami and on the west side of the state it might make sense to widen it.

[Beltway]

How about I-75 in Alligator Alley?

There's actually a surprising amount of traffic considering that the area it passes though has practically no development, and Florida is a growing state.  Whether it's even possible to widen it considering it goes through the Everglades is another matter.

It's probably possible. The right of way and median are pretty wide all the way through and it's already four lanes but with how many people live in Miami and on the west side of the state it might make sense to widen it.

The most rural section carries about 24,000 AADT per 2017 FDOT traffic data.  That is plenty busy, although other than maybe a couple weekends per year would not meet 6-lane warrants.

The median is about 70 feet wide so there is ample space for 2 more lanes.

[adventurernumber1]

How about I-75 in Alligator Alley?

There's actually a surprising amount of traffic considering that the area it passes though has practically no development, and Florida is a growing state.  Whether it's even possible to widen it considering it goes through the Everglades is another matter.

It's probably possible. The right of way and median are pretty wide all the way through and it's already four lanes but with how many people live in Miami and on the west side of the state it might make sense to widen it.

The most rural section carries about 24,000 AADT per 2017 FDOT traffic data.  That is plenty busy, although other than maybe a couple weekends per year would not meet 6-lane warrants.

The median is about 70 feet wide so there is ample space for 2 more lanes.

That is very interesting, and I will admit that was a little surprising (though not too much) to hear.

The Everglades is an extremely desolate and environmentally-sensitive area, but I-75's traffic counts (including that predicted of the future) speak to the massive development on both sides of the Everglades - the very extensive Miami Metro Area to the east, and the rapidly growing population center of southwest Florida. I suspect both sides will only continue to grow at monstrous proportions, so I now could definitely see why I-75 being widened through the Everglades could indeed be warranted in the future.

[sprjus4]

How about I-75 in Alligator Alley?

There's actually a surprising amount of traffic considering that the area it passes though has practically no development, and Florida is a growing state.  Whether it's even possible to widen it considering it goes through the Everglades is another matter.

It's probably possible. The right of way and median are pretty wide all the way through and it's already four lanes but with how many people live in Miami and on the west side of the state it might make sense to widen it.

The most rural section carries about 24,000 AADT per 2017 FDOT traffic data.  That is plenty busy, although other than maybe a couple weekends per year would not meet 6-lane warrants.

The median is about 70 feet wide so there is ample space for 2 more lanes.

The median through the Everglades is consistently 88 feet wide, so you could get away with adding a 12 ft lane + shoulder in each direction, and be left with 64 feet median, FDOT's "standard" on interstate highways / freeways.

I could see it happening in the next 20 years.

[JREwing78]

US-31 north of North Muskegon
US-131 north of Cedar Springs
I-75 north of Standish

I'd adjust accordingly:
US-31 - Definitely north of Montague and Whitehall, it'll be a LONG time before 6-laning will be necessary. South of there, it ramps up considerably - I wouldn't rule out a need for 6-laning before 2070, particularly with weekend traffic and if the US-31 freeway linking Muskegon to Holland ever becomes a thing.

US-131 - I'd say the "Never" breakoff point would be Big Rapids. It's over 20,000 vpd now south of Morely, and 26,000 vpd south of Howard City. Just south of Cannonsville Rd, it's knocking on 30,000 vpd. Big Rapids is ~ 50 miles away from downtown GR, which puts you at about a 45 minute commute from Big Rapids (in ideal conditions). That's long but not unreasonable.

I-75 - Standish is about right. I could see 6-laning possible in 50 years south of there, but north of there you lose the vast majority of the traffic bound for the NE Lower Peninsula via US-23 or M-65, with the rest of it exiting at M-33 and West Branch. You get a bump in traffic with the M-55 multiplex, but it drops precipitously after that. You might see an occasional 3rd lane for climbing pop up in places north of Grayling (south to the US-127 split is already 6-laned).

[JREwing78]

For Michigan's "Never 6-lane" list, I'll add:

US-10 west of M-30 near Midland), aside from the existing 6-lane multiplex with US-127. In fact, I'd wager that M-20 becomes a 6-lane freeway west of M-30 before US-10 does. The only thing that might change that is if MDOT decides to 4-lane M-115 to Cadillac, which would pull Traverse City-bound traffic off I-75.

US-127 north of the US-10 split is definitely in the "Never 6-lane" camp - that is one lonely road north of Harrison. Considerable stretches of (2-lane) US-2 in the U.P. carries more traffic.

In Wisconsin:
US-12 - the freeway section in Walworth County between Genoa City and Elkhorn is pretty safe from 6-laning, at least until or unless Hwy 50 east of Lake Geneva or US-12 in Illinois are built out more.

In general, though, Wisconsin wasn't in the habit of turning lightly-trafficked stretches into freeway.

[JREwing78]

In Ohio:

SR-11 between I-90 (Ashtabula) and Cortland (near Warren and Youngstown) is pretty safe from 6-laning, unless something radically changes in the economy of that entire area (don't hold your breath).

SR-2 west of Sandusky won't grow in traffic significantly until and unless Ohio 4-lanes SR-2 to Oregon. There's little initiative to expand SR-2 when the Ohio Turnpike was recently 6-laned.

The US-20 Fremont and Norwalk bypasses certainly are in the "Never" camp.

[Flint1979]

US-31 north of North Muskegon
US-131 north of Cedar Springs
I-75 north of Standish

I'd adjust accordingly:
US-31 - Definitely north of Montague and Whitehall, it'll be a LONG time before 6-laning will be necessary. South of there, it ramps up considerably - I wouldn't rule out a need for 6-laning before 2070, particularly with weekend traffic and if the US-31 freeway linking Muskegon to Holland ever becomes a thing.

US-131 - I'd say the "Never" breakoff point would be Big Rapids. It's over 20,000 vpd now south of Morely, and 26,000 vpd south of Howard City. Just south of Cannonsville Rd, it's knocking on 30,000 vpd. Big Rapids is ~ 50 miles away from downtown GR, which puts you at about a 45 minute commute from Big Rapids (in ideal conditions). That's long but not unreasonable.

I-75 - Standish is about right. I could see 6-laning possible in 50 years south of there, but north of there you lose the vast majority of the traffic bound for the NE Lower Peninsula via US-23 or M-65, with the rest of it exiting at M-33 and West Branch. You get a bump in traffic with the M-55 multiplex, but it drops precipitously after that. You might see an occasional 3rd lane for climbing pop up in places north of Grayling (south to the US-127 split is already 6-laned).

I always said that I-75 should be six lanes until the northern terminus of US-127. There isn't a need north of there but I would say between MM 164 where it switches between eight lanes and four lanes (the M-13 connector takes and gives one of the two lanes that I-75 loses and gains right there and the other lane just ends or starts there, depending on which direction you are traveling) and MM 188 where US-23 splits off near Standish should be six lanes and then north of that four lanes probably makes the most sense. I've used US-127's northern terminus because I know that's a major point where traffic volumes pickup and drop off, as is M-33 and US-23.

For US-131 I'd go with the northern split with M-46 and run it six lanes all the way to GR and four lanes north of Howard City.

I-75 in the U.P. will never need more than four lanes and the Mackinac Bridge has a daily VPD of around 12,000.

The lowest VPD I can find on I-75 anywhere is around 4,400 VPD between MM 359 and MM 377 in Michigan.

[Flint1979]

I-75 in Michigan starting at MM 162 (the eastern terminus of US-10) and going north sees the following traffic counts per day.

*South of the US-10/M-25 interchange I-75 has a VPD count of around 48,000.
*North of the US-10/M-25 interchange to MM 164 it drops down to around 32,000 and then around 29,000 north of MM 164.
*After MM 168 (Beaver Road) it drops down to around 18,000 which is kind of surprising because Beaver Road isn't a major exit it only has a Mobil gas station. It does lead to the Bay City State Park but anyone heading north will use M-13 to Beaver Road to get there.
*It drops as low as 15,000 before the US-23 split near Standish and then goes back up to around 19,000 north of that so I don't think that's a real big drop off point as it gains more traffic going north.
*After M-33 at MM 202 it goes down to about 14,000 and then drops off to around 8,700 north of the northern M-55 split going towards Houghton Lake. So I think found the drop off point however it does go back up to around 15,000 or so near US-127's northern terminus.
*It maintains about 15,000 or in that general area until the Mackinac Bridge and has very low traffic counts in the U.P. with about 7,900 being the highest in the Sault Ste. Marie area.

[Beltway]

The most rural section carries about 24,000 AADT per 2017 FDOT traffic data.  That is plenty busy, although other than maybe a couple weekends per year would not meet 6-lane warrants.
The median is about 70 feet wide so there is ample space for 2 more lanes.

The median through the Everglades is consistently 88 feet wide, so you could get away with adding a 12 ft lane + shoulder in each direction, and be left with 64 feet median, FDOT's "standard" on interstate highways / freeways.
I could see it happening in the next 20 years.

My figure was an estimate from looking at Google aerials, just a quick estimate.  Either figure provides plenty of space for 2 lanes and 2 full shoulders.

[Flint1979]

The most rural section carries about 24,000 AADT per 2017 FDOT traffic data.  That is plenty busy, although other than maybe a couple weekends per year would not meet 6-lane warrants.
The median is about 70 feet wide so there is ample space for 2 more lanes.

The median through the Everglades is consistently 88 feet wide, so you could get away with adding a 12 ft lane + shoulder in each direction, and be left with 64 feet median, FDOT's "standard" on interstate highways / freeways.
I could see it happening in the next 20 years.

My figure was an estimate from looking at Google aerials, just a quick estimate.  Either figure provides plenty of space for 2 lanes and 2 full shoulders.

That's how I did it as well. I couldn't remember and it's been years since I've been on that stretch of I-75.

[sprjus4]

My figure was an estimate from looking at Google aerials, just a quick estimate.  Either figure provides plenty of space for 2 lanes and 2 full shoulders.

That's how I did it as well. I couldn't remember and it's been years since I've been on that stretch of I-75.

For future reference, you can right click and measure if you're on Google Maps. That's what I did.