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Interstate 238; the Interstate numbering abomination carved out of an otherwise mundane State Highway

How does one make an otherwise unremarkable stretch of State Highway the absolute bane of the road community?  Make a small portion of said State Highway into a Interstate Highway but one that retains it's completely out of grid State Highway number.  One such route does exist; California State Route 238 and it's better known segment Interstate 238.


CA 238/I-238 (I'll be referring to this highway frequently as Highway 238 for simplicity) including a relinquished segment in Hayward is a 16 mile "highway" starting at I-680 in Fremont which heads northwest to I-880 in San Leandro.  Only an approximately 2.1 mile segment of Highway 238 between I-580 and I-880 is part of the Interstate system.

The numbering oddity behind I-238 stems from the fact that California Legislatively does not allow numbering duplication.  In the eyes of the Legislature there is no difference between a State Highway, US Route and Interstate Highway.  That being the said all highways maintained by Caltrans are for all intents and purposes considered State Highways by the California Legislature.  When I-238 was carved out of a section of CA 238 in 1983 all other X80 State Highway numbers were already in use.  Rather than renumbering CA 180 the route number was maintained leading to the infamous I-238 designation.  The change from CA 238 from I-580 to I-880 to I-238 can be seen by comparing the 1982 and 1986 State Highway Map City Inserts.

1982 State Highway Map City Insert

1986 State Highway Map City Insert

The designation of I-238 places it completely out of grid within the overall National Interstate Highway System.  This fact is made worse considering that there is no I-38.  The Interstate Highway numbering convention has primary two digit routes ascending from odd numbers for North/South routes westward from the East Coast.  East/West two digits Interstates ascend in numbers northward from the Mexican border.  Three digit Interstates are supposed to follow a convention of spur route for odd numbers and loop for even numbers.  Since CA 480 was removed from the State Highway in 1991 it would make a perfect grid replacement for I-238 that also follows California State Highway numbering conventions.  That said the Legislature is not likely to make a change nor am I aware of any attempts to do so.

The history of Highway 238 has numerous renumberings and much of it has been in the State Highway system for a long time.  Highway 238 was carved out what was Legislative Route Number 5 between San Jose and Hayward.  Between Hayward and San Leandro the route of Highway 238 was carved out from LRN 228.  According to CAhighways.org LRN 5 was part of the 1909 First State Highway Bond Act while LRN 228 was created in 1947.  Interestingly LRN 228 has a 2 mile segment that was never built which would serve as an access point for a continuation of I-238 west of I-880 to the unbuilt segment of CA 61.

CAhighways.org on CA 238/I-238

The original Signed Highway designation on the Highway 238 corridor was between San Jose and Hayward which was signed as US 48.  US 48 was assigned when the US Route system was implemented in 1926.  US 48 entered downtown Hayward westward likely on Castro Valley Road.  US 48 likely followed Foothill Boulevard and A Street to Mission Boulevard in downtown Hayward.  US 48 likely turned south on Mission Boulevard towards San Jose.  US 48 followed Mission Boulevard south to Warm Springs where it turned south on Warm Springs Boulevard.  In Milpitas US 48 crossed the rails to Main Street which became Oakland Road.  In San Jose US 48 likely followed 13th Street and Santa Clara Street to US 101.  This designation lasted to about 1929 when US 101 was split around San Francisco Bay into US 101W and US 101E.  When US 101E was assigned it took over the route of US 48 from Hayward to San Jose. 

USends.com has a map showing US 48 ending in San Jose which can be seen below.

USends.com on US 48 endpoints

The 1930 State Highway Map shows US 101E running from Hayward to San Jose.

1930 State Highway Map

Sometime in the mid-1930s (likely 1935 when US 50 was extended from Hayward to San Francisco) the split in US 101 was eliminated.  The next Signed Highway to occupy the Highway 238 corridor was CA 17 from downtown San Jose northward to the junction of Warm Springs Boulevard and Mission Boulevard.  CA 17 split northward towards Oakland on Warm Springs Boulevard whereas Mission Boulevard towards Hayward remained unsigned.  This change can be seen on the 1938 State Highway Map .

1938 State Highway Map

At least by 1940 CA 21 was added to the State Highway system and was routed on the Highway 238 corridor on Mission Boulevard between CA 17 in Warm Springs to what is now I-680 near Mission San Jose.

1940 State Highway Map

At least by 1948 CA 9 was extended to US 50 in Hayward on the Highway 238 corridor.  CA 9 multiplexed CA 17 to Warm Springs and CA 21 to Mission San Jose.

1948 State Highway Map

At least by 1955 the Nimitz Freeway was completed north of San Jose to Warm Springs.  Consequently CA 17/CA 9 were moved to the new freeway alignment whereas the previous surface alignment on the Highway 238 corridor from San Jose to Warm Springs became an unsigned part of LRN 5 again.

1955 State Highway Map

Not much changed with the Highway 238 corridor up until 1963.  During the 1964 Highway Renumbering CA 238 was created out of what was largely CA 9 between Hayward and Mission San Jose.  LRN 680 is shown on the 1964 State Highway Map between Mission San Jose and Warm Springs whereas Warm Springs to San Jose is shown as LRN 17.  CA 238 was also consolidated with LRN 228 which was the future I-238 corridor.

1963 State Highway Map

1964 State Highway Map

By 1965 CA 238 is shown routed on LRN 680 from Mission San Jose to San Jose.

1965 State Highway Map

When I-680 was completed between 1970 and 1975 the route of CA 238 was cut back to it's present south terminus at Mission San Jose/Fremont.

1970 State Highway Map City Insert

1975 State Highway Map City insert

In 2009 the route of CA 238 between Industrial Parkway northward through Apple Avenue within the City of Hayward was authorized to be relinquished.   In 2012 the legislative definition of Highway 238 was updated to reflect the relinquishment in Hayward according to CAhighways.org.

With the reliquishment in Hayward  in mind I began my approach to I-238 on what was CA 238 on Foothills Boulevard at Mission Boulevard.  Said intersection was junction of CA 185, CA 92 and CA 238 until through routes were relinquished in downtown Hayward.  CA 238 would have come in from Mission Boulevard on the right and merged onto Foothill Boulevard ahead.  CA 185 began on the left on Mission Boulevard and CA 92 began on Jackson Street headed the opposite direction of the photo.


Foothill Boulevard between Mission Boulevard to A Street was switched to a one-way configuration post relinquishment.  At A Street the route of Foothill Boulevard becomes two-way again.





CA 238 begins again on Foothill Boulevard just slightly north of Grove Way approaching the I-238/I-580 on ramps.


At the I-238/I-580 on ramps traffic can continue on former US 48/US 101E to Castro Valley Boulevard.  The former junction of US 48/US 101E at Foothill Boulevard and Castro Valley Boulevard can be seen in the distance at the top of the hill ahead in the photo below.  The on ramp BGS has some newer Button-Copy shields.


My route on I-238 was towards I-880 southbound.  On ramp traffic on I-238 westward towards I-880 crosses below both I-238 and I-580






I-238 west towards I-880 does have a highway junction with CA 185 at Exit 15.  The Exit numbers on I-238 are reflective of the overall 16 miles I described above for Highway 238 as a whole.



My route on I-238 didn't fully take me to it's terminus as I took exit 16A for I-880 south towards San Jose.  I-238 ends at Exit 17B for I-880 northbound.









CA 238 is still signed from I-238 heading eastward approaching I-580.  I was able to capture a photo of the CA 238 BGS heading onto CA 185 later in the day after I drove I-238 west to I-880.



Comments

Anonymous said…
This is silly, why didn't they just "double shield" it and designate it SR-238 and I-580. In Hollywood we have SR-2 and US-101 on the same freeway, they both have freeway and non-freeway segments.
Anonymous said…
Because I-580 diverges and heads north to parallel I-880. I-238 is a link between I-580 and I-880.

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