Should every major coast-to-coast/border-to-border Interstate be 6+ lanes?

[Avalanchez71]

4 lanes of I-65 and I-40 through Tennessee is more than sufficient.

[sprjus4]

but I-35 between Austin and San Antonio (once completely out of both cities) works just fine with 4 lanes. I suspect the same is true with much of I-35 in Texas.

I-35 between San Antonio and Austin barely works with 6 lanes, let alone 4 lanes.

I-35 between San Antonio and I-35E/W split outside Dallas-Fort Worth has been fully widened to a minimum of 6 lanes, and carries a heavy amount of traffic (around 50,000 AADT with high truck volumes) and plans exist to widen the remainder of I-35E to 6 lanes, and the remainder of I-35 to Oklahoma.

[kphoger]

Absolutely not.  Number of lanes should have nothing to do with how close to the border or ocean a particular route number goes.

If, for example, I-15 north of I-90 were renumbered to I-190, that shouldn't change how many lanes the highway should have.

[kkt]

As far as I-5, it would be a good idea for California to start planning now to make it six lanes from Wheeler Ridge to Shasta Lake.  Four lanes may be sufficient from Shasta Lake to the Oregon Border.

Oregon should plan for six lanes from Roseburg to the Washington Border, and Washington should expand the remaining 2-lane section in Centralia.

Expansions should be case by case based on vehicle count, truck count, and observed congestion.  Interstates should not be specially treated because they are coast to coast or border to border.  ("Sorry, I-40, you end at Bakersfield so NO expansion for you!")

[FrCorySticha]

I'm sorry, but the good people of Shelby, MT, may not need a six lane I-15.

Rather than spend more on pointless widenings, the money should be directed to maintaining what we already have (well, that and completion of 49 and 69).

I live along I-15 south of Great Falls, and there really isn't any part of I-15 in Montana that needs 6 lanes. Some of it would find a super-2 with passing lanes sufficient. Even within the "cities" (Helena, Great Falls, and Butte) there isn't enough traffic to require more than 2 lanes each way.

[TXtoNJ]

Was talking about this with a friend, and I'll propose the same question to you: Should every major coast-to-coast/border-to-border Interstate thoroughfare be at least 6 lanes for its entire length?

One size fits all rarely works well.  Montana will surly object why their I-15 needs to be 6 lanes wide and Wyoming needs I-25 to be 6 lanes wide, when their entire states have smaller populations than many cities.

Even I-80 in Wyoming could stand to be 6 lanes wide, if only for safety purposes. When the winds get going, being next to a 18-wheeler gets dangerous out there.

Is there accident data to support that, or is it just one's comfort level?

What if a truck was in the center lane? You're still gonna be one lane away.

https://www.claimsjournal.com/news/west/2015/04/30/263109.htm
https://kslnewsradio.com/1920305/wyoming-crash-i-80/?

That's not data.  That's news stories of 2 incidents that occurred in extremely bad weather, and doesn't justify widening hundreds of miles of highways.

Ever driven out there?

[kkt]

I have seen suggestions that it would have been better for I-80 to follow the route of US 30.  I've been there once, in January about 20 years ago, but there weren't any big storms then.  Very pretty if you like snowy mountain peaks and wide open country.

[Flint1979]

And other interstates serving as important connecting points:

8/24/44/49/57/59/64/71/eastern 76/77/81/83/91/93

I-94 is not important?

East of Minneapolis it ought to be 6 lanes by these standards.

Between there and the Wisconsin border it can be heavy but east of Hudson I think 4 lanes is enough.

[kphoger]

That's not data.  That's news stories of 2 incidents that occurred in extremely bad weather, and doesn't justify widening hundreds of miles of highways.

Ever driven out there?

Doesn't matter.  It still wouldn't be "data".

And that's what shoulders are for.  If I'm driving in high crosswinds, and I see a double semi trailer swaying in the wind, you can bet I'm riding that shoulder line or even putting two wheels on the other side of it.  That doesn't require a whole additional lane.

Besides, what are you suggesting?  That people would leave the center lane completely empty?  Pass a truck by moving from the right lane clear over to the third lane and then back again?

[sprjus4]

^

Perhaps widening the left shoulder to allow additional maneuvering room? Would be cheaper and address the issue than adding a full lane which traffic volumes wouldn't dictate.

[sprjus4]

If I'm driving in high crosswinds, and I see a double semi trailer swaying in the wind, you can bet I'm riding that shoulder line or even putting two wheels on the other side of it.

I'll usually wait for a straight away and punch it to pass a truck that's swaying, while riding the line.

[TXtoNJ]

That's not data.  That's news stories of 2 incidents that occurred in extremely bad weather, and doesn't justify widening hundreds of miles of highways.

Ever driven out there?

Doesn't matter.  It still wouldn't be "data".

And that's what shoulders are for.  If I'm driving in high crosswinds, and I see a double semi trailer swaying in the wind, you can bet I'm riding that shoulder line or even putting two wheels on the other side of it.  That doesn't require a whole additional lane.

Besides, what are you suggesting?  That people would leave the center lane completely empty?  Pass a truck by moving from the right lane clear over to the third lane and then back again?

Room to maneuver in hazardous situations, along with space for detours in the case of accidents. Expanded shoulders would be useful as well, as suggested above.

And you know as well as I do that data only answers the questions you're asking. AADT is such a sticking point around here, the question of whether we should expand (or contract) for other reasons rarely gets raised.

[jeffandnicole]

That's not data.  That's news stories of 2 incidents that occurred in extremely bad weather, and doesn't justify widening hundreds of miles of highways.

Ever driven out there?

Doesn't matter.  It still wouldn't be "data".

And that's what shoulders are for.  If I'm driving in high crosswinds, and I see a double semi trailer swaying in the wind, you can bet I'm riding that shoulder line or even putting two wheels on the other side of it.  That doesn't require a whole additional lane.

Besides, what are you suggesting?  That people would leave the center lane completely empty?  Pass a truck by moving from the right lane clear over to the third lane and then back again?

Room to maneuver in hazardous situations, along with space for detours in the case of accidents. Expanded shoulders would be useful as well, as suggested above.

And you know as well as I do that data only answers the questions you're asking. AADT is such a sticking point around here, the question of whether we should expand (or contract) for other reasons rarely gets raised.

AADT is a sticking point everywhere. Feds wouldn't fund an expansion if AADT doesn't remotely come close to qualifying.

[epzik8]

Only if the traffic warrants it.