710 - Long Beach Freeway Gap

[silverback1065]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

[cahwyguy]

Of course, the answer would be to number our highways in Hex, but then that's the compusaur in me talking. I think I'll just take the C05 home now :-)

[djsekani]

OK -- let's assume the 710 extension is built (tunnels, surface, whatever) and it, as planned, distributes its traffic flow at the 210/134 interchange.  Where do you think the bulk of rush-hour (locally, between 2:30 and 7:30 p.m.) traffic will go?  If you said it would make a hard right onto east I-210 toward Arcadia, Azusa, and beyond you, as Don Rickles was prone to say, get a cookie!  I'm certain posters who are residing in or are at least familiar with the area would be concerned about dumping several thousand extra cars & trucks on 210 east in the late afternoon; it's miserable enough currently -- and capacity expansion along this section of 210 would be next to impossible.  The only thing that would partially mitigate this would be to install metering lights on the ramp from 710 north to 210 east (which would probably be done in any instance) -- but that would likely back the 710 traffic up into the tunnels (if that were the methodology adopted), requiring an exhaust-evacuation system of extraordinarily high capacity, not to mention an equally high level of expenditure.

IMHO -- regardless of how 710 is to be extended, the implications of the very existence of that corridor in that location, given its potential to impact an area far beyond its own alignment, require a reconsideration of the project as a whole.

Any traffic heading for the 210 East currently clogs up the 605 North during rush hour; the 605-210 interchange is such a massive cluster that it's frequently faster to take surface streets. The 710 extension would possibly relieve some of this congestion, but not by much.

The primary purpose of the 710 would be to serve as a bypass of the East L.A. interchange, particularly for truck traffic coming from the ports. As such the current freeway most likely to be negatively affected is actually the 210 West, which is why the foothill communities like La Canada Flintridge are so opposed to the project. The stretch of the 210 between the 134 interchange and the 5 freeway has one of the lightest rush-hour traffic volumes in the area, and the locals want to keep it that way.

[sparker]

All well and good -- a 710 completion would have the potential to draw north-south truck traffic to and from the ports away from I-5 by simply using the 710/210 combination as a bypass, thus potentially disturbing those folks in La Canada/Flintridge, La Crescenta, and Montrose who have come to see that portion of 210 as more or less undisturbed (folks, I'm originally from Glendale, and can remember the locals' fight about the freeway segment through La Canada that resulted in the I-210 "tunnel" under Foothill Blvd. just east of the CA 2 interchange -- one of my college girlfriends' father was the lead District 7 PE on that design project!).  Foothill folks don't want their bucolic existence disturbed! 

But that isn't my concern here -- an extended I-710 will be considered by regional commuters to be just another N-S link between the northern/I-210 & central/I-10 primary E-W corridors serving such traffic (CA 60 being the southern San Gabriel-Pomona-Ontario corridor).  As such, it will dump afternoon rush-hour traffic onto an already congested 210, which tends to come to a standstill while still in eastern Pasadena; it still has to traverse Sierra Madre, Arcadia, Monrovia, and Duarte before intersecting I-605; presently, that whole section is at best a crawl eastbound after 2:30 p.m.  The saving grace has been that the through freeway route into Pasadena from central L.A. has involved a multiple-facility routing north on I-5, northeast on CA 2, and then east on CA 134 before merging with I-210 from the northwest.  The fact that it's a bit out of the way -- and utilizes other freeways with their own congestion base -- has made it a suboptimal option, which has kept I-210 immediately east of Pasadena no worse than it already is in terms of congestion.  Commuter traffic terminating in Arcadia, Monrovia, and that immediate area is as likely to use I-605 north and then turn west on I-210 (rush-hour contraflow) to get to their destination -- and while it's no picnic, it at least is a workable concept -- much more than adding additional thousands of vehicles onto 210 east in central Pasadena. 

[silverback1065]

Honestly, there is nothing you can do to make LA's traffic acceptable.  To many cars, not enough lanes.  Making it a walkable city years ago could have helped, but honestly there's no amount of walkability that would fix traffic in a city this size with at least 5 million people in the metro area.  Best to grin and bear it.  Can anyone in the area comment on the public transit?  Does LA have a subway system?  Or at least a bus system? I haven't heard good things about their public transit in general.   

[TheStranger]

Making it a walkable city years ago could have helped, but honestly there's no amount of walkability that would fix traffic in a city this size with at least 5 million people in the metro area.

Downtown is pretty walkable...but the suburban reach is much more vast than almost anywhere in the US (save maybe Chicago and New York).  To put it in perspective, while the city limits are a little bonkers south of the USC/Memorial Stadium area, you could theoretically go from one end of the city (San Pedro) to another (Sylmar) in the same distance that it takes to get from San Jose to San Francisco, approximately 40 miles.

Does LA have a subway system?  Or at least a bus system? I haven't heard good things about their public transit in general.   

LA has a pretty extensive bus and light rail system (though the light rail does not reach the airport and likely won't for years to come, with a station a mile or two away) that connects Pasadena, South Central LA, Long Beach, Norwalk, Culver City and East LA...and a smaller subway system that primarily serves downtown and Hollywood (with one planned extension).
http://media.metro.net/riding_metro/maps/images/system_map_2016-0520.gif
http://media.metro.net/riding_metro/maps/images/rail_map.gif

[djsekani]

But that isn't my concern here -- an extended I-710 will be considered by regional commuters to be just another N-S link between the northern/I-210 & central/I-10 primary E-W corridors serving such traffic (CA 60 being the southern San Gabriel-Pomona-Ontario corridor).  As such, it will dump afternoon rush-hour traffic onto an already congested 210, which tends to come to a standstill while still in eastern Pasadena; it still has to traverse Sierra Madre, Arcadia, Monrovia, and Duarte before intersecting I-605; presently, that whole section is at best a crawl eastbound after 2:30 p.m.  The saving grace has been that the through freeway route into Pasadena from central L.A. has involved a multiple-facility routing north on I-5, northeast on CA 2, and then east on CA 134 before merging with I-210 from the northwest.  The fact that it's a bit out of the way -- and utilizes other freeways with their own congestion base -- has made it a suboptimal option, which has kept I-210 immediately east of Pasadena no worse than it already is in terms of congestion.  Commuter traffic terminating in Arcadia, Monrovia, and that immediate area is as likely to use I-605 north and then turn west on I-210 (rush-hour contraflow) to get to their destination -- and while it's no picnic, it at least is a workable concept -- much more than adding additional thousands of vehicles onto 210 east in central Pasadena.

Well, I don't know what to tell you. I'm not a traffic engineer, but I do drive in L.A. almost daily, and personally I don't see a reason why a 710 N to 210 E connection would be as popular as you claim it will be. Any traffic going further east than Duarte will still be taking the 605 N because it's a shorter, more direct route. 605 N to 210 W would still be a faster option to Arcadia and Monrovia, so why would anyone opt to jump into the 210 E slog through Pasadena instead? Besides with rush hour traffic being what it is you can't really make anything that much worse.

Can anyone in the area comment on the public transit?  Does LA have a subway system?  Or at least a bus system? I haven't heard good things about their public transit in general.   

Public transit is one of those things that's mocked by know-nothings that have never been here. We have an extensive system of buses, BRT, commuter (heavy) rail, light rail, and subways. L.A. actually has the second-most popular light rail system in the country, and that's not counting the recent expansions that opened earlier this year. In addition there are two subway expansions and a light rail line to LAX under construction right now, and more projects are in the works. The region's biggest challenge isn't so much the car culture as it is the physical size of the city. It's hard to effectively connect such a sprawling metropolis, even harder when you consider the natural (mountains) and political (NIMBYs) barriers that have to be overcome.

[hm insulators]

The extension is likely to be scrapped. Too many people oppose it. Once the tunnel is canceled, I hope when tunnel opponents bitch about there being too much congestion, someone tells them this is what they wanted.

Hear, hear!

[hm insulators]

All well and good -- a 710 completion would have the potential to draw north-south truck traffic to and from the ports away from I-5 by simply using the 710/210 combination as a bypass, thus potentially disturbing those folks in La Canada/Flintridge, La Crescenta, and Montrose who have come to see that portion of 210 as more or less undisturbed (folks, I'm originally from Glendale, and can remember the locals' fight about the freeway segment through La Canada that resulted in the I-210 "tunnel" under Foothill Blvd. just east of the CA 2 interchange -- one of my college girlfriends' father was the lead District 7 PE on that design project!).  Foothill folks don't want their bucolic existence disturbed! 

But that isn't my concern here -- an extended I-710 will be considered by regional commuters to be just another N-S link between the northern/I-210 & central/I-10 primary E-W corridors serving such traffic (CA 60 being the southern San Gabriel-Pomona-Ontario corridor).  As such, it will dump afternoon rush-hour traffic onto an already congested 210, which tends to come to a standstill while still in eastern Pasadena; it still has to traverse Sierra Madre, Arcadia, Monrovia, and Duarte before intersecting I-605; presently, that whole section is at best a crawl eastbound after 2:30 p.m.  The saving grace has been that the through freeway route into Pasadena from central L.A. has involved a multiple-facility routing north on I-5, northeast on CA 2, and then east on CA 134 before merging with I-210 from the northwest.  The fact that it's a bit out of the way -- and utilizes other freeways with their own congestion base -- has made it a suboptimal option, which has kept I-210 immediately east of Pasadena no worse than it already is in terms of congestion.  Commuter traffic terminating in Arcadia, Monrovia, and that immediate area is as likely to use I-605 north and then turn west on I-210 (rush-hour contraflow) to get to their destination -- and while it's no picnic, it at least is a workable concept -- much more than adding additional thousands of vehicles onto 210 east in central Pasadena.

Sparker, I grew up in La Canada and remember the 210 being built.

[The Ghostbuster]

While the 710 extension to 210 may not be perfect, I still believe it is a needed link in the Los Angeles freeway system.

[sparker]

We could all go back & forth about this ad infinitum -- but the truth of the matter is that the L.A. area is expanding faster than any facility -- or combination of different types of facilities -- can address.  Period.  Any attempt to alleviate the situation, be it a 710 extension, more LR, added or expanded Metrolink service, even adding bus lines -- will be a mere Band-Aid as regards the overall situation.  It's like chasing a ball downhill -- with an ever-steepening slope!  I'm in favor of whatever works and makes some kind of difference; but I'll always call 'em as I see 'em! 

That being said, I am looking forward to exploring the Gold Line extension out to Azusa during my next visit.  When I left SoCal 4 years ago, there were long-range plans for a further extension -- ultimately out to Ontario Airport.  The last news  I heard was that the next segment was going to terminate at the Metrolink station in either north Pomona or Montclair.  Anyone out there have an update on the status of any of these extension proposals?

[Avalanchez71]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Is that documented or is it a hunch?

[silverback1065]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Is that documented or is it a hunch?

My own hunch on the matter.

[Plutonic Panda]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Thank you for the response. That makes sense.

[coatimundi]

though the light rail does not reach the airport and likely won't for years to come, with a station a mile or two away

What about the "Aviation/LAX Station"? I mean, it's just as far as the car rental offices and there's a free bus to it from the terminals. Obviously it's not ideal to have to change trains in Watts to reach Downtown, but it's still a connection. And the Crenshaw Line is theoretically just a couple of years off. I went by there in April and they had made a lot of progress on it.

[sparker]

What's interesting is that there's a connecting track at Watts between the Blue and Green lines -- but it's only used for movement of equipment off the Green Line for maintenance -- the cars on the other lines are incompatible with those on the Green Line (IIRC, because of different station platform clearance standards). 

[cahwyguy]

though the light rail does not reach the airport and likely won't for years to come, with a station a mile or two away

What about the "Aviation/LAX Station"? I mean, it's just as far as the car rental offices and there's a free bus to it from the terminals. Obviously it's not ideal to have to change trains in Watts to reach Downtown, but it's still a connection. And the Crenshaw Line is theoretically just a couple of years off. I went by there in April and they had made a lot of progress on it.

A lot of people think you want light rail to the airport, and by that they mean "to the terminals directly". You don't; you want to do what LA is doing. Here's the explanation I heard. If you are going to the terminals directly, you are stopping at each terminal, and drastically slowing the overall speed of that light rail line to its other points.

What LA is doing is similar to New York (and, IIRC, Chicago). Light rail to a single terminal near the airport, and then some form of Shuttle (in the case of LA, it will be a separate rail line that services both the terminals and a consolidated car rental station).

The LAX/Aviation station is good (I pass by it every day), but people forget about the G shuttle. It's also a pain if you are on the Red Line -- you have to do that Red to Blue to Green dance. For me, I take the Flyaway.

[Bobby5280]

While it might look good on a map, the cost of connecting I-710 to I-210 would be so horribly expensive there wouldn't be enough benefit to justify the sky high price. Building tunnels would probably be the only practical approach to avoid demolishing many dozens of properties. But a tunnel project like that could cost several billion dollars, maybe even $10 billion. And that would be a massive tunnel project in an earthquake prone area.

Downtown is pretty walkable...but the suburban reach is much more vast than almost anywhere in the US (save maybe Chicago and New York).  To put it in perspective, while the city limits are a little bonkers south of the USC/Memorial Stadium area, you could theoretically go from one end of the city (San Pedro) to another (Sylmar) in the same distance that it takes to get from San Jose to San Francisco, approximately 40 miles.

The Dallas-Fort Worth and Houston metro areas both cover a hell of a lot of area. The far reaches of DFW run about 80 miles West to East and over 60 miles South to North. It can easily take over an hour to cross that even late at night when traffic is light.

Even in some "smaller" sprawling cities, like Oklahoma City, there is just too much physical area for mass transit and walk-ability to cover every neighborhood. Plus one needs enough potential passengers to make anything like a light rail line cost effective. I think it's downright absurd just how expensive light rail lines can be. It's easy for a modest project to cost over a billion dollars. Bus lines are far less expensive, but who really enjoys taking the bus? It can be kind of ghetto in some respects.

Oklahoma City has been doing a great job improving its downtown core. It's taking a much longer time to make other areas more walkable. ODOT and suburb city councils have been making stupid, short-sighted mistakes in regional planning for things future highway expansion needs. Texas is pretty good at doing that and the Houston and Dallas areas both have growing light rail systems too.

What LA is doing is similar to New York (and, IIRC, Chicago). Light rail to a single terminal near the airport, and then some form of Shuttle (in the case of LA, it will be a separate rail line that services both the terminals and a consolidated car rental station).

Dallas has a similar setup. The DART light rail line going to DFW ends at terminal B. There is a separate rail system that goes around the DFW terminals and parking areas.

[coatimundi]

The LAX/Aviation station is good (I pass by it every day), but people forget about the G shuttle. It's also a pain if you are on the Red Line -- you have to do that Red to Blue to Green dance. For me, I take the Flyaway.

That dance is problematic, and I never recommend people try that. If they're coming from LAX and going Downtown, I just suggest the Flyaway.

Both Midway and O'Hare airports have the single stop. Actually, most airports do: Washington Reagan, BWI, ATL, Cleveland (which, btw, was the first airport in the US to have a direct rail transit connection), Newark, PHX, SFO, OAK, San Jose, Seattle, etc. The only one I can think of that has the actual light rail line stop at each terminal is MSP, but they only have two terminals. I'm fairly certain that, when I rode it, it only went to one of the terminals, but that was years ago and I could be wrong.
Dallas Love also has an "airport stop," but it's a couple of miles away. However, you get a free transfer between the bus and the light rail. But that bus is a pain. I rode it to get Downtown a few months ago and it took a really long time. Once you start requiring bus transfers, then it becomes a much less attractive option. I've had several problems at San Jose, and I've written VTA each time trying to get them to not see it as a regular bus service but, rather, an airport connector, as it's supposed to be. I think that, if this bus (and all of these buses) operated more as an airport shuttle, they would have more success.

But, oh goodness, this is quite off topic. To get it back: I noticed that they had "light rail alternatives" in the 710 alternatives document. Seems like they should build both a freeway and a light rail, the latter to connect the two Gold Line segments. Though that may be more useful farther east.

[Henry]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Is that documented or is it a hunch?

My own hunch on the matter.

Well, how do you explain the 4-digit state routes that exist in KY, LA and (as secondary routes) VA?

[silverback1065]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Is that documented or is it a hunch?

My own hunch on the matter.

Well, how do you explain the 4-digit state routes that exist in KY, LA and (as secondary routes) VA?

That's state not federal, but I'm not saying it's impossible or not a good idea, just a hunch. I guess you could argue H-201 is sort of a 4 digit highway. What should the rules be on a federal 4 digit route? Curious for others ideas

[Henry]

Rereading this discussion, I noticed one comment that was never corrected:

But it would be harder to justify having I-710 on the western Foothill.  This freeway is still primarily east/west and should not be numbered with a north/south number.  It needs a new number.

Pay attention closely, boys and girls and those who decline to be identified: Both 210 and 710 are three digit interstates. The notion of odd being N/S and even being E/W is true for two digit interstates (5 is N/S, 10 is E/W, 80 is E/W, 15 is primarily N/S). When you get to the three digits, you need to do modulo arithmetic. Remember that? So, for a three digit interstate xyy (e.g., 710, 580, 280, 210), the last two digits (xx) represent the parent interstate that the route touches / goes near / goes through). The first digit (y) being even is generally a loop route around an area (405, 605, and even 210 are good examples of that). The first digit odd is generally a spur into an area (thus 710 is a spur into Long Beach, 110 a spur to the port, 780 a spur off of 680). For 3dis, there is no n/s or e/w rule to the numbering.

And before you say anything, yes, there are anomalies (like 205) and bad anomalies (like 238). Deal.

(ETA: For the number purests out there: If they ever connect 710 and 210, what would make sense would to make the route an x05 route, as it is a loop off the 405, but all the even x05s are taken (205, 405, 605, 805), and even most of the spur x05s are taken (105, 305 (assigned as FAI, but not signed), 505, 905). 705 would be the only open route, and most wouldn't think of it as a spur. As for the x10 numbers, well, I'm sure the discussion has been turned into a dead horse.)

There are similar rules for both US and state routes -- see all the gory details at http://www.cahighways.org/numberng.html

This might be a really dumb question but I am still learning a lot about interstates and highways. . . is it not possible to have a four digit interstate?

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Is that documented or is it a hunch?

My own hunch on the matter.

Well, how do you explain the 4-digit state routes that exist in KY, LA and (as secondary routes) VA?

That's state not federal, but I'm not saying it's impossible or not a good idea, just a hunch. I guess you could argue H-201 is sort of a 4 digit highway. What should the rules be on a federal 4 digit route? Curious for others ideas

I guess you're right.

[The Ghostbuster]

There are no 4-digit US Highways or 4-digit Interstate Highways (Except possibly Interstate H-201). There's no reason to start bringing them into existence now!

[kkt]

4 digits are not allowed and shouldn't ever be really, a 4 digit highway implies that it is a child route of a 3 digit route which isn't necessary

Is there a written law or policy against 4-digit interstate numbers?  I didn't think there was.

[coatimundi]

There isn't, so 238 could have theoretically been 1880 or 1580 (a spur child of either 880 or 580), but this is more a system pf precedence and not of codified rules. There's a reason it doesn't exist elsewhere: because it doesn't exist elsewhere.