Six or more lane highways that could work as four laners

[Roadgeekteen]

Can't think of any but I'm sure there are some.

[Avalanchez71]

I-65 in KY.  I-75 in GA.  I-95 in FL.

[Rothman]

I-65 in KY.  I-75 in GA.  I-95 in FL.

Nah.

[sprjus4]

I-464 in Hampton Roads.

While 6 lanes is certainly nice to have, it could suffice with just 4 lanes, albeit heavy.

The highway carries around 50,000 AADT, compared to 4 lane VA-168 to the south which carries nearly 80,000 AADT.

I-664 was built around the same time, with only 4 lanes, and carries 70,000 - 90,000 AADT. This would've been the better choice for 6 lane construction vs. I-464, though that would present issues with the bridge tunnel. I-664 on the Peninsula is 6 lanes and needs it.

[Bruce]

SR 99 on the Aurora Bridge in Seattle.

The bridge is too narrow to safely have six lanes, with buses and trucks having to straddle a pair to get across. Ideally there would also be a median barrier to prevent head-on and crossover crashes like the infamous one in 2015 involving a charter bus and a duck boat.

[kphoger]

For the first few years I lived in Wichita, I thought the Canal Route (I-135) was over-built and could function fine as a four-lane highway.  Then my work hours changed and I saw what it's like during rush hour.  Nope!

[pianocello]

I'm guessing very few. Seems like agencies are more likely to upgrade 2-lane roads to 4 than 4-lane roads to 6+, so the 6-lane roads are very carefully thought out.

If I had to choose a candidate for this thread, I'd go with I-55 in central Illinois, but like most of these examples, the third lane is nice to have around.

[TheHighwayMan3561]

I thought of this question once the other thread appeared. My first thought was possibly something somewhere in Detroit, though I couldn't specifically say what.

[GaryV]

Many places around Detroit could use more lanes.  I can't think of any that could be reduced.  At off-peak times the capacity isn't fully used, but it sure clogs up during those peaks.

[Roadgeekteen]

Many places around Detroit could use more lanes.  I can't think of any that could be reduced.  At off-peak times the capacity isn't fully used, but it sure clogs up during those peaks.

If the city keeps losing population that could change /s/.

[Tom958]

I-75 south of Macon, from I-475 to the next interchange north at Pio Nono Avenue.

[Roadgeekteen]

I-95 north of MA 128 always seemed a bit overbuilt.

[Flint1979]

Many places around Detroit could use more lanes.  I can't think of any that could be reduced.  At off-peak times the capacity isn't fully used, but it sure clogs up during those peaks.

If the city keeps losing population that could change /s/.

It doesn't have much to do with the city losing population, the metro area is bigger today than it was when Detroit was at it's peak population by about a million people. Detroit's freeways do need to be expanded, I-94 is only six lanes through the city but indeed warrants more lanes. And plus Detroit sits on the busiest border crossing between Canada and the United States.

[Rothman]

Many places around Detroit could use more lanes.  I can't think of any that could be reduced.  At off-peak times the capacity isn't fully used, but it sure clogs up during those peaks.

I don't know.  They were able to fully close I-96 for reconstruction relatively recently.

[CtrlAltDel]

I-26 south (or if you prefer, east) of the North Carolina/Tennessee border is 6 lanes with an AADT of 12,000, which seems on the low side.

I-65 in KY.  I-75 in GA.  I-95 in FL.

How so?

[US 89]

I-65 in KY.  I-75 in GA.  I-95 in FL.

As somebody with personal experience on I-75 in Georgia, that absolutely needs its six lanes.

[Great Lakes Roads]

The only one that "could" work is I-475 through Flint.

[Flint1979]

Many places around Detroit could use more lanes.  I can't think of any that could be reduced.  At off-peak times the capacity isn't fully used, but it sure clogs up during those peaks.

I don't know.  They were able to fully close I-96 for reconstruction relatively recently.

They also had I-75 coming into the city from the south closed for a couple of years recently.

[Flint1979]

I-65 in KY.  I-75 in GA.  I-95 in FL.

As somebody with personal experience on I-75 in Georgia, that absolutely needs its six lanes.

No question I-75 needs to be six lanes in Georgia. Heck in some areas it could even be eight lanes.

[webny99]

I-65 in KY.  I-75 in GA.  I-95 in FL.

As somebody with personal experience on I-75 in Georgia, that absolutely needs its six lanes.

No question I-75 needs to be six lanes in Georgia. Heck in some areas it could even be eight lanes.

No one is disputing that it needs at least six lanes from the Tennessee line to at least Macon.
Once you get south of Macon, however, four lanes could work, at least in the sense that many other roads nationwide with similar volumes (the Thruway in NY, parts of I-81 and I-78 in PA, etc.) have just four lanes and are not being seriously considered for widening.

If the question is "Should I-75 in Georgia should be reduced to four lanes?", then the answer is definitely No.
If the question is "Would I-75 south of Macon function reasonably well with four lanes?" the answer is probably Yes.

[jeffandnicole]

I-65 in KY.  I-75 in GA.  I-95 in FL.

As somebody with personal experience on I-75 in Georgia, that absolutely needs its six lanes.

No question I-75 needs to be six lanes in Georgia. Heck in some areas it could even be eight lanes.

No one is disputing that it needs at least six lanes from the Tennessee line to at least Macon.
Once you get south of Macon, however, four lanes could work, at least in the sense that many other roads nationwide with similar volumes (the Thruway in NY, parts of I-81 and I-78 in PA, etc.) have just four lanes and are not being seriously considered for widening.

If the question is "Should I-75 in Georgia should be reduced to four lanes?", then the answer is definitely No.
If the question is "Would I-75 south of Macon function reasonably well with four lanes?" the answer is probably Yes.

Would you also be in favor of reducing the speed limit to 65 mph on a 4 lane I-75 in Georgia? If you're comparing volumes to a 4 lane 78/81 in PA/NY, you would need to compare the speed limit as well.

[Ketchup99]

I can't think of any in Pennsylvania - so few roads have six lanes to begin with. Certainly there are parts of I-80 in western NJ that have 6-8 lanes that could be would in Pennsylvania, but I'm not sure that's NJ's problem.

[webny99]

Would you also be in favor of reducing the speed limit to 65 mph on a 4 lane I-75 in Georgia? If you're comparing volumes to a 4 lane 78/81 in PA/NY, you would need to compare the speed limit as well.

I'm not sure I see the relevance of the speed limit. But in any case, no, I would never advocate for a lower speed limit unless there was a legitimate safety concern.

[Ketchup99]

I-65 in KY.  I-75 in GA.  I-95 in FL.

As somebody with personal experience on I-75 in Georgia, that absolutely needs its six lanes.

No question I-75 needs to be six lanes in Georgia. Heck in some areas it could even be eight lanes.

No one is disputing that it needs at least six lanes from the Tennessee line to at least Macon.
Once you get south of Macon, however, four lanes could work, at least in the sense that many other roads nationwide with similar volumes (the Thruway in NY, parts of I-81 and I-78 in PA, etc.) have just four lanes and are not being seriously considered for widening.

If the question is "Should I-75 in Georgia should be reduced to four lanes?", then the answer is definitely No.
If the question is "Would I-75 south of Macon function reasonably well with four lanes?" the answer is probably Yes.

Would you also be in favor of reducing the speed limit to 65 mph on a 4 lane I-75 in Georgia? If you're comparing volumes to a 4 lane 78/81 in PA/NY, you would need to compare the speed limit as well.

I think the issue here is that I-78 has very substandard geometry in places, and anyways, much of I-81 should most definitely be 70, even with existing traffic volumes. I-75 in Georgia is not saddled with poor geometry or a low-speed-limit DOT in the same way.

[I-55]

I-65 in KY.  I-75 in GA.  I-95 in FL.

As somebody with personal experience on I-75 in Georgia, that absolutely needs its six lanes.

No question I-75 needs to be six lanes in Georgia. Heck in some areas it could even be eight lanes.

During any sort of holiday/vacation travel period I-65 is packed, if anything it needs the 6 lane extended into IN and TN (which has recently begun in both states). I-75 needs to be 6 lanes for hurricane evacuation as well as normal traffic days. I don't have as much experience on I-95 but I would imagine in FL it would follow the same justification as I-75.