Interstate "Indigestion" 238

I-238 at a Glance Interstate 238
Location: Hayward and San Lorenzo, CA; south of Oakland
Length: 2 miles.
Fun Facts:
  • It is the only three digit Interstate without a "parent" Interstate as there is no I-38, nor will there ever be one.
  • It is the only Interstate whose number was directly transferred from an existing state or US highway number. It was previously CA-238.
  • It gives road buffs headaches since it violates the Interstate Highway numbering conventions
  • It was approved by AASHTO, which lends it an air of credibility since I-99, the other extreme violation had its designation written into law instead of being approved by AASHTO.
  • It exists since at the time of its inception there were no other I-x80 numbers available in California.


What is Interstate 238 and why the big deal? This is a question that I'm sure 99% of the population asks and is what I will address on this page. By way of introduction Interstate 238 is many a road buff's nightmare, at the very least it gives them indigestion, as Scott "Kurumi" Oglesby points out. However, it may now be outdone by Bud Schuster's I-99. It's easy to see why it does not go very well with road buffs: it is a clear violation of the Interstate Highway numbering convention. First, there is no I-38, which would be its "parent." If there was an I-38, it would probably be located several lines of latitude south; it would certainly be nowhere near the Bay Area. This means that I-238 has no business existing, much less being located in the Bay Area. While this is absolutely true, there is more to the I-238 designation than appears on the surface.

To begin with, I feel there is a lot of misplaced antagonism toward this highway. All the other sites that I have seen about I-238 decry its existence and point out, sometimes in exquisite detail, how it violates the system. There is a sound basis for these arguments, but they only tell one side of the story. I have written this page to offer a different point of view and to help make sense of what would otherwise seem a complete calamity as well as answering David "ZZYZX" Steinberg's question, "What were they thinking?!"

Some of you who are reading this are probably familiar with my explanations for I-238 from the misc.transport.road newsgroup. I think there are some valid reasons for I-238. By themselves they probably do not justify this highway, but taken together they do. After all, there is "I99" which has absolutely no justification for existing outside of one man's unmitigated greed and egotism.

The History Behind I-238

I-238 started life as California SR-238. In fact, the non-freeway portion remains as signed SR-238. In 1983 the portion of SR-238 between I-580 and I-880 (the Highway Formerly Known as SR-17) became I-238 since that portion received Interstate Highway funding to be upgraded. A freeway had been there before, but it resembled Disneyland's Autopia more that a safe road to drive. This project coincided with the upgrading of I-580, which was still the same as when it carried the US 50 shield, 30 years previously. However, the population in the Bay Area had at least doubled during that time, making the existing freeways obsolete and upgrades necessary. On the surface, I-238 seems a piddling road, but in reality it serves a very important function. Before its upgrade, SR-238 westbound only directly connected to SR-17 (I-880) northbound. If people wanted to go to San Jose from I-580, they had to get off the freeway and negotiate local traffic to get to SR-17 south. With its completion as I-238, there was a direct freeway to freeway connection between I-580 and San Jose, the Silicon Valley and other cities in the southern Bay Area. In the larger picture, this meant there was a direct connection between I-5 (via I-580) and the southern Bay Area. In a sense this makes I-238 a glorified, albeit important, off ramp. Interestingly, despite these improvements, the route is laden with congestion and many continue to use surface street alternatives. However, this is further evidence which testifies to the value of the upgraded freeway.

Why I-238?

I have heard many different reasons for this section of SR-238 becoming I-238. Most explanations center around possible drug use by Caltrans and AASHTO (who approved the routing - more later). I've also heard stupidity and arrogance cited as factors. What I have not heard that often is something which really approaches the truth. Bear in mind that this aberration, this travesty as some would say, came about because of a lot of little reasons that amounted to this end.

The first fact to establish is why it was desirable for I-238 to carry an Interstate shield. There are two different types of funding that can be given to an Interstate highway: chargeable and non-chargeable. A chargeable Interstate is one that is considered part of the 42,000 mile network of highways, and as a result gets the full 90% funding by the federal government. A non-chargeable Interstate looks and feels exactly like its counterpart except that it is funded by the same means as US Highways and qualifying state highways. The Interstate shield is optional, but it is desirable since it promotes continuity within a region's highway network. I should also point out here that I have heard a lot of people proposing new Interstates; for example converting SR-99 to I-7 or giving the Loop Routes in and around Phoenix, AZ I-x10 numbers. This is much the same reason as Caltrans would want to see more Interstates, at least in the Bay Area.

I-238 was approved as a non-chargeable Interstate. This means that Caltrans could have left well enough alone and kept Route 238 signed entirely as a state highway. However, during the late 1980s Caltrans was working fast and furiously to upgrade the Bay Area's remaining state highways to Interstate standards and to upgrade the existing Interstates. SR-17, a fixture along the East Bay since the 1930s became I-580 and I-880. Even the portion of SR-24, another ancient fixture in the area, between SR-17/I-880 and I-580 became I-980. Why I-980 was not extended to I-680 or further is beyond me to explain. Even more to the point, why it was not applied to SR-238 with SR-24 remaining is even further beyond me to figure out. However US 101 and SR-238 (the two mile freeway portion) are left as the only non-Interstate within the immediate network of freeways in the north part of the Bay Area. US 101 is widely recognized while SR-238 is not.

Of course the fact that all the other freeways were upgraded to Interstates does not mean that the same had to be done for SR-238. In fact it made no difference in the funding or construction whether or not it had an Interstate shield. Route 238 would be exactly the same today whether it remained as a State highway or was upgraded to Interstate highway status. However, there is a compelling reason to make Route 238 into I-238, protestations of road buffs aside. It boils down to three words: brand name recognition.

Hands down the Interstate highway shield is one of the most widely recognized reassurance markers in the world, and possibly exceeds even the STOP sign. This makes it a "brand name" the same as Tylenol or Nike. The California state highway shield (the miner's spade) is also widely known, but compared to the Interstate shield rates as more of a "generic" brand.

Giving the little two mile section of road an Interstate designation allows it to fit in with the rest of the extensive Interstate system in the Bay Area and lends an air of continuity. For those who get lost easily or for out of town travelers, this alleviates a lot of confusion that would otherwise ensue and makes it consistent with the rest of the highway system. Most travelers are not concerned so much about the way the numbers inside the shield fit into the system so much as there is an Interstate shield. The shield gives "brand name" recognition to this stretch of highway.

Saying brand name recognition does not really satisfactorily address why I-238 did not remain signed as a state highway. After all, SR-85 and SR-87 as well as SR-13, SR-24, SR-242 (ad infinitum) were not signed differently, although they do meet the Interstate standards. However, of all the state route freeways, 238 was the only one that started and ended at Interstates - in fact they constitute most of it anyway; off ramps and all. Making SR-238 into an interstate eliminates this discontinuity.

"That's great Casey," you say, "but what does that have to do with this road being I-238? Why not give it an x80 number? I hear 180 and 480 are available." The answer is simple: in the late 1980s there were no x80 numbers available in California. 180 is currently assigned to a state highway which runs from I-5 to the middle of Kings Canyon, and is a very old routing that dates back from the inception of the California state highway system. This is significant since California has a strict policy of not repeating numbers within the state. So 180 cannot be both a state and Interstate highway. There was talk in the late 70's of making what is now the portion of I-580 between I-80 and US 101 into I-180. This never came to fruition (though it would have been a logical move) possibly due to California's reluctance to resign the already well-established SR-180. So it should be clear that 180 could never really be a consideration.

However, don't just take my word for it. I received email from Joseph Rouse, at the time a student assistant from Caltrans. Here is what he had to say.

I have a copy of a letter from AASHTO director Francis Francois to former Caltrans director Leo Trombatore, dated July 7, 1983, giving official notice of the Interstate approval, at about the same time I-180 was eliminated and replaced by the extension of I-580 into Richmond and SR-17 was converted to I-880. The text is as follows:

Caltrans' Division of Highways and Programming Chief Donald Watson replied in a letter dated July 27, 1983, as follows:

On a related note, some years ago there was a proposal put forth to build a bay crossing that would have linked I-238 with I-380 near San Francisco Airport. That would have easily eliminated the I-238 mess. I don't know what became of that plan.

The above correspondence should prove that I-238 is not a flagrant violation that was allowed to occur just for the fun of it. While AASHTO did have the legitimate suggestion of using I-180 instead, the reply points out that 180 was an already established number. It also shows that AASHTO conceded that resigning the route as I-580 would be expensive, at least in the sense that considerable resigning would be required. Of course, the most important piece of information is that AASHTO did approve it.

The story of the number 480 is quite a bit different, however. When I-238 was conceived, 480 had already been assigned to that god-awful monstrosity, the Embarcadero Freeway, known otherwise as the "World's Longest Off-ramp." In my opinion, if 480 had come to its full fruition before San Francisco blocked it, it would have been such a complete disaster. It was supposed to skirt the waterfront between the Bay Bridge and the Golden Gate Bridge, which I think would have seriously tarnished San Francisco's charm. Anyway, SR-480 started its life as I-480, being designated as such between its completion in 1957 and August, 1965. Apparently someone realized what a travesty this freeway was and that it did not even deserve to be called an Interstate, resulting in its redesignation as SR-480. As is well known, the 1989 Loma Prieta earthquake condemned this freeway, much to the joy of just about everyone except for Caltrans. Route 480 (its ghost and all) was finally put to rest in 1991 and deleted from the state highway system, certainly with tears of sorrow from the eyes of Caltrans engineers falling on the order. While 480 is available now, it certainly was not back in 1988, which left I-238 as a remotely reasonable alternative. I-480 could rise from its ashes and replace I-238, but that will almost certainly not happen, and I'll explain why shortly.

So What Could or Should be Done?

I've heard a lot of proposals for the future disposition of I-238. Renumber it, say to I-480. Have it revert to being signed as a state highway. Renumber I-580 to I-705. Keep I-238 and build an I-338 to help alleviate traffic on I-680. And so on. I happen to think there is a lot of merit to these suggestions (although I-338 may be a little extreme as of yet), but I think the wisest course of action would be to leave it alone. Like it or not, I-238 is a legitimate Interstate; it was approved by AASHTO. Bear in mind that AASHTO is the organization that is responsible for maintaining and assigning the numbers for Interstate (as well as US) highways. This is significant since I-99, Bud Schuster's loathsome, detestable and vile pork barrel highway that it is, was designated by law, by brute force. As I understand it, that means it never had to be legitimized by AASHTO. So if Mr. Schuster wanted, he could have had his little project designated as Interstate 1 (which I'm surprised he didn't since he obviously thinks he is #1) or even as I-38 without having to be accountable to anyone but himself. So say what you might about I-238, but remember that Caltrans did not play God and had to have AASHTO approve it. I'm sure AASHTO did not approve it just for the heck of it.


Interstate 480There are some compelling arguments to be made for renumbering I-238. The I-480 designation has now been freed up and could be applied to that section of highway. It is a perfect candidate for an even numbered "3di" as it forms a (small) loop. It starts at I-880 and ends at I-580; a even numbered 3di in theory starts and ends at an Interstate, whether it is a parent or daughter route. It would also make it somewhat noteworthy as it would be one of the few 3dis that does not touch its parent Interstate, much like I-380. However, I feel that even this solution is not needed and could very well prove impractical. I-480 is deeply entrenched in the minds of people in the Bay Area. Even though it no longer exists, it would certainly cause some confusion if it were to be reincarnated. Perhaps more to the point, it would bring a lot of the old antagonism back to the surface from its days as the Embarcadero Freeway; antagonism that is best left in the past.


Interstate 580From here, the suggestions grow more extreme and more complex. Renumber I-580 to something like I-305 and apply the I-580 designation to what is now I-238. While this suggestion makes a good deal of sense and is perfectly "legal" as far as the numbering scheme is concerned, it is something that would have made more sense to do in the early 1960s before I-580 was established in the first place. Don't get me wrong here; I think I-305 (or I-705) is a much better choice for that stretch of highway than I-580. The cost of resigning all 76 miles of I-580 would be significant, to say the least. The overheads would have to be redone and all the shields (which cost Caltrans $25+ a pop) on all the on-ramps and along the freeway would have to be replaced. What is of more pressing concern is the confusion that such a renumbering would create. It's one thing if I-580 were to disappear altogether; it's another that it becomes a two mile long freeway right next to its former location. The confusion that would be created by renumbering this 40+ year old freeway would be incredible - and costly. Getting rid of I-238 is not important enough to merit a solution like that.


Interstate 338Scott Oglesby ("Kurumi") has suggested building another x-38 in the Bay Area; I-338. This is a one-way "toll free" freeway that ends one mile into the San Francisco Bay off of Fremont. This would legitimize (to an extent) I-238 and solve a very nasty traffic problem. However, I think there are those who may have a moral objection to sending Bay Area commuters to the bottom of San Francisco Bay, although I have a moral objection to not doing so. Nevertheless, this would probably not go over too well, especially with Bay Area commuters who may take a dim view to such a traffic solution.


Interstate 980A sensible suggestion, and to me the only feasible one, would be to renumber I-238 to I-980. SR-24 could once again extend south to I-880 as it did before. The cost of replacing shields would be very minor and there would not be a lot of confusion since most of I-980 is marked either as "To I-580", "To I-880", or simply as "SR-24 North." My only objection, and this reaches to the crux of my argument, is that it simply is not worth doing; it is not worth changing I-238 to anything, especially since it is such a short highway. Then again, the more I think about it, the more I realize that transferring I-980 and restoring SR-24 makes a lot of sense, enough I'm sure to render my arguments moot. Realistically (and in the end that's what counts), I think any Caltrans engineer would laugh his head off when told to change I-238.

There are many more solutions to this that people have come up with and I'll list a few more. As mentioned in Mr. Rouse's email, there was a proposal to build a new Bay Bridge between I-380 on the west and Route 238 on the East Bay. A quick glance at the map showed me that this would have been built across the widest part of the bay, making it less than feasible. This would have been nice, though, since it would have eliminated I-238, replacing it with I-380 and it would have helped Bay Area commuters. Some of the others did not seem so reasonable. I heard proposals by road buffs to have an I-3 in place of US 101 or to extend I-70 west. The only real purpose for creating these would be to add more 3di's for the sole purpose of eliminating I-238. C'mon, it's just a trivial thing; not worth throwing a lot of money at.

I think I've made my point. The bottom line is that there are no reasons compelling enough to go to the expense and effort of redesignating I-238, loathsome as it may be to some. In all honesty, 99% of the population neither knows nor cares what Route 238 is; whether it's an Interstate highway, a state highway, or signed by a mauve rhombus shaped shield with paisley, polka dots and lots of pretty flowers. All they care about is that I-238 gets them to where they need to go without too much trouble or confusion. For better or worse, I-238 does its job and is certainly here with us to stay. While it is in violation of the numbering convention, there are a lot of legitimate reasons for it being so and its existence should not be considered offensive, just unique. If that does not put things into context, then I suggest comparing it with I-99. After all, at least there are good reasons for I-238 to exist.

Links to Related Pages

Here are some other pages related to I-238 and (ulp!) I-99.

David "Zzyzx" Steinberg's I-238 Page and I-99 Page.

Kurumi's I-238 and I-338 Page by Scott Oglesby

Pennsylvania Interstate 99 Travel Page. Need to know where the exit is in Bald Eagle?

Interstate 99

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