What Portions of the Interstate System are Open to Bicycles?

[Beltway]

I'd rather ride my bike on an interstate with wide shoulders and minimal driveways/cross streets, even with 70+ MPH traffic, than a 2 lane road with narrow or no shoulders, more driveways and cross streets, and 50+ MPH traffic. Most interstates (excluding some urban ones where you probably aren't allowed, and some older bridges) have quite wide shoulders. State or US routes, total crapshoot.

Not sure how dangerous it would be with the typical 10 foot paved right shoulders, but unless the shoulder is kept well-swept there would be gravel and other debris on the shoulder.  It would also be a very noisy environment, with the tire noise and engine noise and wind noise of cars and trucks at Interstate speed, and there would be blasts of wind from trucks.

I have not biked an Interstate, but I have biked the new VA-147 Huguenot Bridge over the James River in Richmond.

I use the bridge several times per week and the average number of pedestrians and bicyclists on the bridge at any one time is probably 1.0 or less.  I walked the new bridge once and biked it once, it has a great view of the river but it is very noisy with all the high speed traffic (45 mph limit), so that is likely why even with UR nearby very few pedestrians and bicyclists use the bridge.  The shoulders are 10 feet wide and the sidewalks are 5 feet wide, so there is plenty of space for pedestrians and bicyclists.  I felt safe enough but it was a very noisy experience.

That is 45 mph and very few large trucks.  Now imagine 70 mph and lots of large trucks!

[Beltway]

Remember that the standards of the I-system make for exceedingly safe bicycling on lower traffic routes, such as many of them in the west - looooong sight lines and wide paved right shoulders give plenty of room and visibility.
Mike

Most rural Interstates in the west now carry 20,000 AADT or more, traffic has steadily increased over the years.  Some segments carry a lot less, such as the northernmost reaches of I-15 and I-29, but the east-west routes in particular carry heavy car and truck traffic.

Safe but noisy (see my other post).

[texaskdog]

I-72 (US 36, MSR 110) crossing the Mississippi River between Illinois and Missouri: The shoulders (no sidewalk/path) are open to the first exit on each side of the river (photos taken July 2017):

come on can't even just put up an updated sign?

[texaskdog]

Remember that the standards of the I-system make for exceedingly safe bicycling on lower traffic routes, such as many of them in the west - looooong sight lines and wide paved right shoulders give plenty of room and visibility.

Mike

We have problems on the divided highway of Loop 360. Bikers think it's this great biking highway and there is really too much traffic for it (divided highway).   If underpasses were put under exit and entrance ramps (or bikes were required to also exit) I would think most rural freeways with wide shoulders would be okay for bikes.

[froggie]

Remember that the standards of the I-system make for exceedingly safe bicycling on lower traffic routes, such as many of them in the west - looooong sight lines and wide paved right shoulders give plenty of room and visibility.
Mike

Most rural Interstates in the west now carry 20,000 AADT or more, traffic has steadily increased over the years.  Some segments carry a lot less, such as the northernmost reaches of I-15 and I-29, but the east-west routes in particular carry heavy car and truck traffic.

Safe but noisy (see my other post).

I opted to test the first part of your theory.  Below is a map showing estimated 2017 AADT volumes for the Interstate system.  Base data year is 2012 (most recent year I could find at a national level).  An 8.4% growth factor was applied based on national VMT trends between 2012-2017.



While each east-west Interstate across the Rockies and the Great Plains has some 20K+ AADT segments, each has lengthy segments that are below 20K AADT.  Each also has at least one segment that drops below 10K AADT, with I-40 being the only one that doesn't consistently drop below 10K for lengthy segments.  The same also applies to I-15, I-25, and I-29.  I-5, the Arizona north-south Interstates, and I-35 are busier, but even I-35 has several segments north of OKC that are below 20K AADT as does I-5 between Redding, CA and Medford, OR.

[Beltway]

Most rural Interstates in the west now carry 20,000 AADT or more, traffic has steadily increased over the years.  Some segments carry a lot less, such as the northernmost reaches of I-15 and I-29, but the east-west routes in particular carry heavy car and truck traffic.

I opted to test the first part of your theory.  Below is a map showing estimated 2017 AADT volumes for the Interstate system.  Base data year is 2012 (most recent year I could find at a national level).  An 8.4% growth factor was applied based on national VMT trends between 2012-2017.

Who compiled that data?  I can't believe that those segments of I-80 and I-70 are less than 10,000 AADT.

That is the volume on VA I-64 across North Mountain in Rockbridge County, extremely low by eastern standards.

[silverback1065]

who here is an avid cyclist?  I cycle regularly, when I do, i try to keep it off road as much as possible.  Too many distracted drivers!  There are a lot of multi-use paths where I live, so I ride on those. 

[seicer]

I am.

When I was in Austin, Texas for holiday/work a few years back, I had to bike on the shoulders of several freeways - which were marked for cyclists and were popular touring routes for many others. It was necessary in many cases because getting to the hills would have otherwise been impossible or downright awful. It felt completely safe, separated by traffic, and the shoulders were generally very clean.

I've also biked on other freeways/expressways, such as Corridor H/US 48 in eastern West Virginia.

I find it easier to bike on those types of roads for long distance travels.

[silverback1065]

i think the biggest problem, at least in my experience, is that the shoulders are full of junk, making it not a good place to ride.   

[Bickendan]

Remember that the standards of the I-system make for exceedingly safe bicycling on lower traffic routes, such as many of them in the west - looooong sight lines and wide paved right shoulders give plenty of room and visibility.
Mike

Most rural Interstates in the west now carry 20,000 AADT or more, traffic has steadily increased over the years.  Some segments carry a lot less, such as the northernmost reaches of I-15 and I-29, but the east-west routes in particular carry heavy car and truck traffic.

Safe but noisy (see my other post).

I opted to test the first part of your theory.  Below is a map showing estimated 2017 AADT volumes for the Interstate system.  Base data year is 2012 (most recent year I could find at a national level).  An 8.4% growth factor was applied based on national VMT trends between 2012-2017.



While each east-west Interstate across the Rockies and the Great Plains has some 20K+ AADT segments, each has lengthy segments that are below 20K AADT.  Each also has at least one segment that drops below 10K AADT, with I-40 being the only one that doesn't consistently drop below 10K for lengthy segments.  The same also applies to I-15, I-25, and I-29.  I-5, the Arizona north-south Interstates, and I-35 are busier, but even I-35 has several segments north of OKC that are below 20K AADT as does I-5 between Redding, CA and Medford, OR.

What I find interesting is that I-10 between El Paso and I-20 has between 10-20k AADT, and that's the segment with at grades.

[froggie]

Who compiled that data?  I can't believe that those segments of I-80 and I-70 are less than 10,000 AADT.

FHWA, via the respective (and required) state DOT data submittals.

Having been on it, I can definitely believe I-70 being less than 10K through Utah.

[US 89]

Who compiled that data?  I can't believe that those segments of I-80 and I-70 are less than 10,000 AADT.

FHWA, via the respective (and required) state DOT data submittals.

Having been on it, I can definitely believe I-70 being less than 10K through Utah.

Especially west of the US 6 split at Green River, through the San Rafael Swell (the longest interstate segment without services—110 miles). East of that junction you can get some areas of higher traffic, especially during tourist season (though still less than 10,000 AADT).

[SectorZ]

who here is an avid cyclist?  I cycle regularly, when I do, i try to keep it off road as much as possible.  Too many distracted drivers!  There are a lot of multi-use paths where I live, so I ride on those.

I am. After 25 years and 100K+ miles of riding, cars barely bother me at this point.

[inkyatari]

who here is an avid cyclist?

I am.  Mostly road riding, as the only bike trail near me is long, straight and boring.  I haven't gotten out much this year yet, as the combination of the weather and full force depression has kept me indoors.

[Hurricane Rex]

i'm not sure why anyone would want to ride a bike on the interstate, that sounds incredibly scary and dangerous!

Try running on one.

Oregon allows bikes in most areas on interstates except for certain areas in Portland and Medford.

LG-TP260

[silverback1065]

there is a national bike route system, US BR-XX.  35 and 50 go through my metro area.

[texaskdog]

so why do so many of the red highways still only have 2 lanes each way?

[hotdogPi]

so why do so many of the red highways still only have 2 lanes each way?

20000 isn't that high.

[froggie]

so why do so many of the red highways still only have 2 lanes each way?

Because, depending on the specifics of the roadway in question (exit spacing, ramp volumes, number of trucks, and several other variables), one typically doesn't start seeing heavy congestion on such roadways until you're well north of 40K daily volume (in some cases north of 60K).

I used 20K as the threshold to test Scott's hypothesis that most western Interstates had that volume level or higher.

[Beltway]

so why do so many of the red highways still only have 2 lanes each way?

Because, depending on the specifics of the roadway in question (exit spacing, ramp volumes, number of trucks, and several other variables), one typically doesn't start seeing heavy congestion on such roadways until you're well north of 40K daily volume (in some cases north of 60K).
I used 20K as the threshold to test Scott's hypothesis that most western Interstates had that volume level or higher.

I still can't see I-80 across Nevada having less than 10,000 AADT.  That would seem to be at least 18-20,000 or more.

[froggie]

^ Believe it.  I found Nevada DOT's 2016 traffic reports for verification and dug through.  Except between Carlin and Elko, I-80 in Nevada doesn't get above 10K once you're past Fernley (where ALT US 50 splits).  It drops as low as 5,400 near the Utah border.

[Beltway]

^ Believe it.  I found Nevada DOT's 2016 traffic reports for verification and dug through.  Except between Carlin and Elko, I-80 in Nevada doesn't get above 10K once you're past Fernley (where ALT US 50 splits).  It drops as low as 5,400 near the Utah border.

That is surprising for a transcontinental route that connects the cities that I-80 directly serves, including Sacramento and the S.F. Bay area just to the west of there.

That would demontrate the silliness of the proposals for an Interstate highway connecting Carson City to Las Vegas, which would undoubably have far lower traffic volumes.

[rarnold]

They will be on the New 74 bridge in the Quad Cities just like 72...

...sort of. With the bridge reconstruction, they're going to add in a pedestrian/bicycle path on the Illinois-bound side, but it will be separated from vehicular traffic by at least a barrier.

I'm pretty sure bicycles are banned on all freeways in Iowa as well.

As they should be. Bicycles have no business on an interstate highway designed for high-speed vehicle traffic.

[Bruce]

They will be on the New 74 bridge in the Quad Cities just like 72...

...sort of. With the bridge reconstruction, they're going to add in a pedestrian/bicycle path on the Illinois-bound side, but it will be separated from vehicular traffic by at least a barrier.

I'm pretty sure bicycles are banned on all freeways in Iowa as well.

As they should be. Bicycles have no business on an interstate highway designed for high-speed vehicle traffic.

...Except that many interstates were built over the only possible alternative, so cyclists wanting to traverse places like the Columbia River Gorge's south side have no choice but to use the interstate (and are encouraged to do so by DOTs).

[silverback1065]

who here is an avid cyclist?

I am.  Mostly road riding, as the only bike trail near me is long, straight and boring.  I haven't gotten out much this year yet, as the combination of the weather and full force depression has kept me indoors.

i am too!