Interstate 238
Encyclopedia
Interstate 238 is a short auxiliary route of the Interstate Highway System
in the San Francisco Bay Area
, California
, United States
. Part of State Route 238 until 1983, and still considered the same route (part of Route 238) by the California Department of Transportation
(Caltrans), it connects Interstate 580
in Castro Valley (where SR 238 continues south) with Interstate 880 in San Leandro. Despite running in an east–west direction, it is signed north–south, as the rest of Route 238 is more north–south than east–west.
The number does not follow established rules for numbering Interstates, as there is no Interstate 38. Of the nine possible numbers ending in 80 (as it connects two auxiliary routes of Interstate 80), two (180 and 480) were in use by State Routes (the latter an Interstate until 1968), and the seven others were used by other Interstates. (I-880 was designated at the same time as I-238; it too could be only an auxiliary route of I-80.)
This route is part of the California Freeway and Expressway System
.
to San Leandro
, Caltrans officially signs it as a north–south freeway since the rest of State Route 238
is more north–south. The south (or east) terminus of I-238 is at its interchange with Interstate 580
and SR 238 in Castro Valley. From there, it enters into the southern portion of the census-designated place
of Ashland
, running parallel to its border with Cherryland
. Then after entering San Leandro, I-238 terminates at Interstate 880.
I-238 and I-880 is used as an alternate truck route between Castro Valley and Oakland
; trucks over 4.5 tons are prohibited through the latter on I-580.
; it was pre-1964 Legislative Route 228 (along with an unbuilt extension west to unbuilt State Route 61, which is still included in the Route 238 definition).
The segment from what is now I-580 to I-880 was built as a freeway in 1956. The rest of SR 238 south to Interstate 680
in Fremont was also planned to be upgraded to a freeway (parallel to present I-880), but after it was unsuccessfully submitted to the Interstate Highway System in October 1968, and after several lawsuits, it never got off the ground.
When present Interstate 880 was added to the Interstate Highway System as a renumbering of part of State Route 17, the short piece of SR 238 connecting I-880 to I-580 was also added; both were non-chargeable routes (not eligible for Interstate Completion funds). Both numbers — I-238 and I-880 - were approved by the American Association of State Highway and Transportation Officials
(AASHTO) on July 7, 1983. The interchange
s with I-580 and I-880 were rebuilt from 1988 to 1994, in part to add missing ramps between I-238 and I-880 towards the south. Prior to the completion of the ramps, access was provided by Hesperian Boulevard.
As the American Association of State Highway and Transportation Officials
said on July 7, 1983, when approving the designation,
Caltrans responded on July 27, 1983:
With the deletion of State Route 480 in 1991, the "480" designation is once again available. However, there has been no push since then to renumber I-238 to I-480.
resistance standards.
The entire route is in Alameda County
.
{| class=wikitable
!Location
!Postmile
!Exit
!Destinations
!Notes
|-
|rowspan=2|Castro Valley
|R14.47
|14
|
|Southbound exit and northbound entrance
|-
|R14.47
|
|
|Southbound exit and northbound entrance
|-
|Ashland
|14.95
|15
|
|
|-
|rowspan=4|San Leandro
|bgcolor=#ffdddd|16.28
|bgcolor=#ffdddd|16B
|bgcolor=#ffdddd|Hesperian Boulevard – San Lorenzo
|bgcolor=#ffdddd|Northbound exit and southbound entrance
|-
|16.70
|16A
|, San Mateo Bridge
|Northbound exit and southbound entrance
|-
|16.70
|17A
|Washington Avenue
|Northbound exit and southbound entrance
|-
|16.70
|17B
|
|Northbound exit and southbound entrance
Interstate Highway System
The Dwight D. Eisenhower National System of Interstate and Defense Highways, , is a network of limited-access roads including freeways, highways, and expressways forming part of the National Highway System of the United States of America...
in the San Francisco Bay Area
San Francisco Bay Area
The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Part of State Route 238 until 1983, and still considered the same route (part of Route 238) by the California Department of Transportation
California Department of Transportation
The California Department of Transportation is a government department in the U.S. state of California. Its mission is to improve mobility across the state. It manages the state highway system and is actively involved with public transportation systems throughout the state...
(Caltrans), it connects Interstate 580
Interstate 580 (California)
Interstate 580 is an 80-mile east–west Interstate Highway in Northern California. The heavily traveled spur route of Interstate 80 runs from San Rafael in the San Francisco Bay Area to Interstate 5 near Tracy in the Central Valley...
in Castro Valley (where SR 238 continues south) with Interstate 880 in San Leandro. Despite running in an east–west direction, it is signed north–south, as the rest of Route 238 is more north–south than east–west.
The number does not follow established rules for numbering Interstates, as there is no Interstate 38. Of the nine possible numbers ending in 80 (as it connects two auxiliary routes of Interstate 80), two (180 and 480) were in use by State Routes (the latter an Interstate until 1968), and the seven others were used by other Interstates. (I-880 was designated at the same time as I-238; it too could be only an auxiliary route of I-80.)
This route is part of the California Freeway and Expressway System
California Freeway and Expressway System
The California Freeway and Expressway System is a system of existing or planned freeways and expressways in the U.S. state of California. It is defined by the Streets and Highways Code.-List of roads in the system:*State Route 1 *State Route 2...
.
Route description
Although the 2.16 miles (3.5 km) I-238 goes in an east–west direction from Castro ValleyCastro Valley, California
Castro Valley is a census-designated place in Alameda County, California, United States. As of the 2000 census, it is the fifth most populous unincorporated area in California, and the twenty-third in the United States...
to San Leandro
San Leandro, California
San Leandro is a city in Alameda County, California, United States. It is considered a suburb of Oakland and San Francisco. The population was 84,950 as of 2010 census. The climate of the city is mild throughout the year.-Geography and water resources:...
, Caltrans officially signs it as a north–south freeway since the rest of State Route 238
California State Route 238
State Route 238 is a north–south highway in the U.S. state of California. The route is a divided multilane surface highway in the southeastern part of the San Francisco Bay Area. SR 238 connects Interstate 580 in Castro Valley and Interstate 680 in Fremont.-Route description:SR 238 goes...
is more north–south. The south (or east) terminus of I-238 is at its interchange with Interstate 580
Interstate 580 (California)
Interstate 580 is an 80-mile east–west Interstate Highway in Northern California. The heavily traveled spur route of Interstate 80 runs from San Rafael in the San Francisco Bay Area to Interstate 5 near Tracy in the Central Valley...
and SR 238 in Castro Valley. From there, it enters into the southern portion of the census-designated place
Census-designated place
A census-designated place is a concentration of population identified by the United States Census Bureau for statistical purposes. CDPs are delineated for each decennial census as the statistical counterparts of incorporated places such as cities, towns and villages...
of Ashland
Ashland, California
Ashland is a census-designated place in Alameda County, California, United States. The population was 21,925 at the 2010 census.-Geography:...
, running parallel to its border with Cherryland
Cherryland, California
Cherryland is a census-designated place in Alameda County, California, United States.The unincorporated community is located between the cities of San Leandro to the north and Hayward to the south...
. Then after entering San Leandro, I-238 terminates at Interstate 880.
I-238 and I-880 is used as an alternate truck route between Castro Valley and Oakland
Oakland, California
Oakland is a major West Coast port city on San Francisco Bay in the U.S. state of California. It is the eighth-largest city in the state with a 2010 population of 390,724...
; trucks over 4.5 tons are prohibited through the latter on I-580.
History
The section of road that is now I-238 had no signed number before the 1964 renumbering1964 state highway renumbering (California)
In 1963 and 1964, the California Division of Highways implemented a major renumbering of its state highways. The majority of sign routes — those marked for the public — kept their numbers; the main changes were to the legislative routes, which had their numbers changed to match the sign routes...
; it was pre-1964 Legislative Route 228 (along with an unbuilt extension west to unbuilt State Route 61, which is still included in the Route 238 definition).
The segment from what is now I-580 to I-880 was built as a freeway in 1956. The rest of SR 238 south to Interstate 680
Interstate 680 (California)
Interstate 680 is a north–south Interstate Highway in Northern California. It curves around the eastern cities of the San Francisco Bay Area from San Jose to Interstate 80 at Cordelia, bypassing cities along the eastern shore of San Francisco Bay such as Oakland and Richmond while serving...
in Fremont was also planned to be upgraded to a freeway (parallel to present I-880), but after it was unsuccessfully submitted to the Interstate Highway System in October 1968, and after several lawsuits, it never got off the ground.
When present Interstate 880 was added to the Interstate Highway System as a renumbering of part of State Route 17, the short piece of SR 238 connecting I-880 to I-580 was also added; both were non-chargeable routes (not eligible for Interstate Completion funds). Both numbers — I-238 and I-880 - were approved by the American Association of State Highway and Transportation Officials
American Association of State Highway and Transportation Officials
AASHTO, the American Association of State Highway and Transportation Officials, is a standards setting body which publishes specifications, test protocols and guidelines which are used in highway design and construction throughout the United States...
(AASHTO) on July 7, 1983. The interchange
Interchange (road)
In the field of road transport, an interchange is a road junction that typically uses grade separation, and one or more ramps, to permit traffic on at least one highway to pass through the junction without directly crossing any other traffic stream. It differs from a standard intersection, at which...
s with I-580 and I-880 were rebuilt from 1988 to 1994, in part to add missing ramps between I-238 and I-880 towards the south. Prior to the completion of the ramps, access was provided by Hesperian Boulevard.
As the American Association of State Highway and Transportation Officials
American Association of State Highway and Transportation Officials
AASHTO, the American Association of State Highway and Transportation Officials, is a standards setting body which publishes specifications, test protocols and guidelines which are used in highway design and construction throughout the United States...
said on July 7, 1983, when approving the designation,
Caltrans responded on July 27, 1983:
With the deletion of State Route 480 in 1991, the "480" designation is once again available. However, there has been no push since then to renumber I-238 to I-480.
Future
The entire length of I-238 is being reconstructed, including a reconfigured interchange with I-880, and an added travel lane in each direction. The existing pavement is being removed to allow for the roadbed to be rebuilt, then new pavement will be laid. Additionally, almost all of the bridges and overpasses are being replaced with new ones meeting current earthquakeEarthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
resistance standards.
Exit list
- Note: Except where prefixed with a letter, postmiles were measured in 1964, based on the alignment as it existed at that time, and do not necessarily reflect current mileage.
The entire route is in Alameda County
Alameda County, California
Alameda County is a county in the U.S. state of California. It occupies most of the East Bay region of the San Francisco Bay Area. As of the 2010 census it had a population of 1,510,271, making it the 7th most populous county in the state...
.
{| class=wikitable
!Location
!Postmile
!Exit
Exit number
An exit number is a number assigned to a road junction, usually an exit from a freeway. It is usually marked on the same sign as the destinations of the exit, as well as a sign in the gore....
!Destinations
!Notes
|-
|rowspan=2|Castro Valley
Castro Valley, California
Castro Valley is a census-designated place in Alameda County, California, United States. As of the 2000 census, it is the fifth most populous unincorporated area in California, and the twenty-third in the United States...
|R14.47
|14
|
|Southbound exit and northbound entrance
|-
|R14.47
|
|
|Southbound exit and northbound entrance
|-
|Ashland
Ashland, California
Ashland is a census-designated place in Alameda County, California, United States. The population was 21,925 at the 2010 census.-Geography:...
|14.95
|15
|
|
|-
|rowspan=4|San Leandro
San Leandro, California
San Leandro is a city in Alameda County, California, United States. It is considered a suburb of Oakland and San Francisco. The population was 84,950 as of 2010 census. The climate of the city is mild throughout the year.-Geography and water resources:...
|bgcolor=#ffdddd|16.28
|bgcolor=#ffdddd|16B
|bgcolor=#ffdddd|Hesperian Boulevard – San Lorenzo
San Lorenzo, California
San Lorenzo , also known as San Lorenzo Village is a census-designated place in Alameda County, California, United States. The population was 23,452 at the 2010 census.-Geography:...
|bgcolor=#ffdddd|Northbound exit and southbound entrance
|-
|16.70
|16A
|, San Mateo Bridge
|Northbound exit and southbound entrance
|-
|16.70
|17A
|Washington Avenue
|Northbound exit and southbound entrance
|-
|16.70
|17B
|
|Northbound exit and southbound entrance
External links
- Indigestion 238: A history of the route and a full explanation of its numbering
- Kurumi - I-238 California