View source for Interstate 780

{{short description|Interstate Highway in California}}
{{Use mdy dates|date=December 2022}}
{{Use American English|date=December 2022}}
{{Infobox road
|state=CA
|type=I
|route=780
|section=623
|map={{maplink-road|from=Interstate 780.map}}
|map_custom=yes
|map_notes=I-780 highlighted in red
|length_mi=6.5
|length_ref=<ref>{{cite web |date=December 31, 2021 |title=Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways |url=https://www.fhwa.dot.gov/planning/national_highway_system/interstate_highway_system/routefinder/table02.cfm |access-date=July 13, 2022 |work=FHWA Route Log and Finder List |publisher=[[Federal Highway Administration]] |archive-date=February 13, 2023 |archive-url=https://web.archive.org/web/20230213083642/https://www.fhwa.dot.gov/planning/national_highway_system/interstate_highway_system/routefinder/table02.cfm |url-status=live }}</ref>
|established=1973-1976
|history=State highway in 1935; Interstate (as I-680) in 1955; renumbered I-780 in 1973–76
|spur_type=I
|spur_of=80
|direction_a=West
|terminus_a={{jct|state=CA|I|80}} in [[Vallejo, California|Vallejo]]
|direction_b=East
|terminus_b={{jct|state=CA|I|680}} in [[Benicia, California|Benicia]]
|counties=[[Solano County, California|Solano]]
|previous_type=I
|previous_route=710
|next_type=I
|next_route=805
}}
[[File:Western End of Interstate 780.jpg|thumb|Western end of Interstate 780 at the interchange with Interstate 80 in Vallejo]]
'''Interstate&nbsp;780''' ('''I-780''') is an east–west [[auxiliary Interstate Highway]] in the [[San Francisco Bay Area]] of [[Northern California]]. It runs from the intersection of Curtola Parkway and Lemon Street in [[Vallejo, California|Vallejo]] east to [[Interstate 680 (California)|I-680]] just north of the [[Benicia–Martinez Bridge]] in [[Benicia, California|Benicia]]. It closely parallels the [[Carquinez Strait]] for its entire route. Originally, this segment was part of I-680 before that Interstate was extended and rerouted to [[Fairfield, California|Fairfield]]. The city-maintained '''Curtola Parkway''' continues west to [[California State Route 29|State Route&nbsp;29]] (SR&nbsp;29) in Vallejo.

==Route description==
The I-780 state-maintained [[freeway]] begins at Lemon Street and Curtola Parkway, quickly crossing underneath [[Interstate 80 in California|I-80]] at a [[cloverleaf interchange]]. The freeway passes through parts of unincorporated Solano County, then heads southeast along the [[Benicia State Recreation Area]] (a [[marsh]]). It then bypasses downtown [[Benicia, California|Benicia]] through the hills to the north. I-780 ends at [[Interstate 680 (California)|I-680]] at the north end of the [[Benicia–Martinez Bridge]], with I-680 heading south through the [[East Bay]] to [[San Jose, California|San Jose]].<ref name=maps>[[Google Maps]] street maps and [[USGS]] [[topographic map]]s, accessed February 2008 via [http://mapper.acme.com/ ACME Mapper] {{Webarchive|url=https://web.archive.org/web/20080102075829/http://mapper.acme.com/ |date=January 2, 2008 }}</ref>

I-780 is part of the [[California Freeway and Expressway System]]<ref name="cafes">{{CAFESystem}}</ref> and, as with every Interstate Highway, is part of the [[National Highway System (United States)|National Highway System]],<ref name=fhwa-nhs>{{FHWA NHS map|region=sanfrancisco|access-date=July 23, 2017}}</ref> a network of highways that are considered essential to the country's economy, defense, and mobility by the [[Federal Highway Administration]] (FHWA).<ref name=NHS-FHWA>{{FHWA NHS}}</ref>

==History==
By 1914, a [[paved road|paved]] [[county road]] connected [[Vallejo, California|Vallejo]] and [[Benicia, California|Benicia]] north of the [[Carquinez Strait]],<ref name="grinnon041914">{{cite news | title=Road News from All Over The State | work=Oakland Tribune | date=15 May 1914 | last=Grinnon | first=Edmund | quote=Vallejo to Benicia. paved road; to Napa, paved to county line, rough to one mile beyond city of Napa;}}</ref> following the present Maine Street, Benicia Road, Columbus Parkway, and K Street.<ref name=bluebook>Official [[Automobile Blue Book]], [https://books.google.com/books?id=Mt0NAAAAYAAJ Volume Eight], 1917, pp. 146, 180</ref> Although [[state highway]]s were designated to Benicia in 1910 ([[Legislative Route 7 (California pre-1964)|Legislative Route (LRN) 7]], now [[Interstate 680 (California)|I-680]]) and Vallejo in 1931 ([[Legislative Route 74 (California pre-1964)|LRN&nbsp;74]], now [[California State Route 29|SR&nbsp;29]]), this connection was not added until 1935, when LRN&nbsp;74 (an unsigned designation) was extended east from Vallejo to Benicia and north along former LRN&nbsp;7 to [[Fairfield, California|Fairfield]].<ref>{{cite CAstat|year=1935|ch=274|p=959, 281}}: "Route 74 is from a point on Route 8 near the Napa Y to Cordelia via Vallejo and Benicia."</ref> (A short spur connecting Vallejo to the [[Carquinez Bridge]] was added to LRN&nbsp;74 in 1937.<ref>{{cite CAstat|year=1937|ch=219|p=515}}: "Route 74 is from a point on Route 8 near the Napa Y to Cordelia via Vallejo and Benicia, including a connection from Vallejo to Route 7 near the Carquinez Bridge."</ref>) LRN&nbsp;74 initially entered Benicia on K Street and left on East 5th Street, making several turns in between.<ref name=bluebook/><ref>[[United States Geological Survey]], [https://web.archive.org/web/20110719150325/http://sunsite2.berkeley.edu/lizardtech/iserv/calcrgn?cat=histopo&item=brk00000052_10a.sid&wid=600&hei=500&style=generic%2Fview.xsl&plugin=true Carquinez Strait] (scale 1:62500), 1940</ref> Two realignments were built in the 1940s, reducing the number of turns to one, at the corner of L and East 2nd streets.<ref name=NBI>[[National Bridge Inventory]] database, 2006: the bridges on East Second Street north of Benicia are dated 1942 and 1944; the pedestrian bridge over Curtola Parkway is dated 1987</ref><ref>[[United States Geological Survey]], [https://web.archive.org/web/20110719150401/http://sunsite2.berkeley.edu/lizardtech/iserv/calcrgn?cat=histopo&item=brk00000275_10a.sid&wid=600&hei=500&style=generic%2Fview.xsl&plugin=true Benicia] (scale 1:24000), 1950</ref>

On September 15, 1955, the [[Bureau of Public Roads]] approved the [[Interstate Highway System]] spurs and connections in urban areas. Among these was a loop around the [[San Francisco Bay]], soon numbered [[Interstate 280 (California)|I-280]] and [[Interstate 680 (California)|I-680]]. The east half (I-680) incorporated a number of existing legislative routes, including [[Legislative Route 69 (California pre-1964)|LRN&nbsp;69]], [[Legislative Route 108 (California pre-1964)|LRN&nbsp;108]], [[Legislative Route 107 (California pre-1964)|LRN&nbsp;107]], [[Legislative Route 75 (California pre-1964)|LRN&nbsp;75]], and [[Legislative Route 74 (California pre-1964)|LRN&nbsp;74]], crossing the [[Carquinez Strait]] on the proposed [[Benicia–Martinez Bridge]] and ending at [[Interstate 80 in California|I-80]] near downtown Vallejo.<ref>[[Bureau of Public Roads]], [[General Location of National System of Interstate Highways]], 1955: [[:Image:San Francisco, California 1955 Yellow Book.jpg|San Francisco]]</ref><ref name=selected>[[California Department of Transportation]], [http://www.dot.ca.gov/hq/tsip/hseb/products/state_highway_routes_selected_information_1995_revised.pdf State Highway Routes: Selected Information] {{Webarchive|url=https://web.archive.org/web/20070316231706/http://www.dot.ca.gov/hq/tsip/HSEB/products/state_highway_routes_selected_information_1995_revised.pdf |date=March 16, 2007 }}, 1994 with 1995 revisions, pp. 342, 348</ref> The first piece of this freeway north of the Carquinez Strait was at the I-80 [[cloverleaf interchange]], built in the late 1950s when I-80 was upgraded through Vallejo. This was an extremely short roadway, beginning at Lemon Street, crossing under I-80 and Laurel Street and ending at Reis Avenue and Cedar Street.<ref name=bridgelog>{{Caltrans bridgelog|date=July 2007}}</ref><ref>[[United States Geological Survey]], [https://web.archive.org/web/20110719150409/http://sunsite2.berkeley.edu/lizardtech/iserv/calcrgn?cat=histopo&item=brk00000276_10a.sid&wid=600&hei=500&style=generic%2Fview.xsl&plugin=true Benicia] (scale 1:24000), 1959</ref> In about 1960, it was extended east to the old highway (Columbus Parkway) between the cities and was completed to the new bridge in about 1962, the year the bridge opened.<!--I can't find details--><ref name=bridgelog/>

{{infobox road small
|state=CA
|type=CA
|route=141
|location=[[Vallejo, California|Vallejo]]
|formed=1964
|deleted=1988
}}
In the [[1964 state highway renumbering (California)|1964 state highway renumbering]], the legislative designation of the completed Vallejo–Benicia freeway was changed from LRN&nbsp;74 to LRN&nbsp;680, reflecting its Interstate designation. The short piece of nonfreeway in Vallejo, extending west from I-80 to [[California State Route 29|SR&nbsp;29]], became '''State Route&nbsp;141''' ('''SR&nbsp;141''').<ref name=law-renumbering>{{cite CAstat|year=1963|ch=385|p=1182, 1189}}: "Route 141 is from Route 80 to Route 29 in Vallejo." "Route 680 is from Route 280 in San Jose to Route 80 in Vallejo passing near Warm Springs, Mission San Jose, Scotts Corners and Sunol, and via Walnut Creek and Benicia."</ref> This route followed Benicia Road and Maine Street, the same alignment the state highway had always taken; it initially connected with I-780 via Lemon Street<ref>[[Division of Highways (California)|Division of Highways]], [http://cahighways.org/maps/1963sfbay.jpg San Francisco and Vicinity] {{Webarchive|url=https://web.archive.org/web/20071231013131/http://www.cahighways.org/maps/1963sfbay.jpg |date=December 31, 2007 }}, 1963</ref> but later followed Benicia Road from I-80 north of I-780. In 1975, a proposed (and never constructed) extension west and north to [[California State Route 37|SR&nbsp;37]] east of the [[Napa River]] was added to LRN&nbsp;141.<ref>[[California Department of Transportation]], [http://cahighways.org/maps/1986sfbay.jpg San Francisco and Vicinity] {{Webarchive|url=https://web.archive.org/web/20071231013133/http://www.cahighways.org/maps/1986sfbay.jpg |date=December 31, 2007 }}, 1986</ref><ref>{{cite CAstat|year=1975|ch=1078|p=2638}}: "Route 141 is the westerly extension of Route 680 from Route 80 to Route 37."</ref> The route was to be the '''Waterfront Freeway''', scaled down to a boulevard in 1974.<ref>[[Vallejo Times Herald]], No Freeway for Waterfront Blvd, April 25, 1974</ref><ref>[[Vallejo Times Herald]], Vallejo Approves Measure to Speed Waterfront Boulevard Construction, August 20, 1974</ref><!--why are 1974 articles referring to the extension to SR 37, when that wasn't added legislatively until 1975? was Caltrans planning it beforehand?-->

The [[Federal Highway Administration|FHWA]] approved a relocation of I-680 onto the [[State Route 21 (California)|SR&nbsp;21]] freeway between Benicia and [[Fairfield, California|Fairfield]] in July 1973. To keep the route to Vallejo in the Interstate system, it was renumbered I-780;<ref name=selected/> the corresponding legislative changes were made in 1976.<ref>{{cite CAstat|year=1976|ch=1354|p=6178}}: "Route 780 is from Route 680 at Benicia to Route 80 in Vallejo."</ref> As part of the project to construct a new northbound [[Benicia–Martinez Bridge]], the I-680/I-780 interchange was rebuilt;{{When|date=February 2011}} the new span opened in August 2007.<ref>[[Metropolitan Transportation Commission (San Francisco Bay Area)|Metropolitan Transportation Commission]], [http://www.mtc.ca.gov/news/press_releases/rel418.htm Rep. George Miller to Keynote Celebrations for Completion of New Benicia-Martinez Bridge]{{dead link|date=January 2013}}, August 23, 2007</ref> LRN&nbsp;141 was deleted from the state highway system in 1988,<ref>{{cite CAstat|year=1988|ch=106|p=443}}</ref> soon after the city of Vallejo constructed Curtola Parkway over (replacing Maryland Street) just to the south, directly connecting I-780 with a surface road to [[California State Route 29|SR&nbsp;29]].<ref name=NBI/>

==Exit list==
Mileage was measured from east-to-west based on the alignment of [[Interstate 680 (California)|LRN&nbsp;680]] as it existed at that time. Exit numbers were still assigned the conventional west-to-east ascension.<ref name=calnexus/>
{{CAinttop|exit
|length_ref=<ref name=calnexus/><ref name=trucklist>{{Caltrans trucklist}}</ref>
|exit_ref=<ref name=calnexus>{{cite web |date=March 17, 2020 |publisher=[[California Department of Transportation]] |work=[[California Numbered Exit Uniform System]] |url=https://dot.ca.gov/-/media/dot-media/programs/safety-programs/documents/exit/calnexus-i-780-03-2020-a11y.pdf |title=Interstate 780 Freeway Interchanges |access-date=October 17, 2020 |archive-date=October 18, 2020 |archive-url=https://web.archive.org/web/20201018203403/https://dot.ca.gov/-/media/dot-media/programs/safety-programs/documents/exit/calnexus-i-780-03-2020-a11y.pdf |url-status=live }}</ref>
|county=Solano
}}
{{CAint|exit
|location=Vallejo
|lspan=7
|mile=6.75
|mspan=2
|exit=—
|road=Curtola Parkway
|notes=Continuation beyond Lemon Street
}}
{{CAint|exit
|mile=none
|exit=—
|road=Lemon Street
|notes=Western terminus; [[at-grade intersection]]
}}
{{CAint|exit
|mile=6.70
|mspan=2
|exit=1A
|road={{Jct|state=CA|I|80|dir1=west|city1=San Francisco}}
|notes=I-80 exit 30A
|nspan=2
}}
{{CAint|exit
|mile=none
|exit=1B
|road={{Jct|state=CA|I|80|dir1=east|city1=Sacramento}}
|notes=none
}}
{{CAint|exit
|mile=6.58
|mspan=2
|exit=1C
|espan=2
|road=Laurel Street
|notes=Eastbound signage
}}
{{CAint
|mile=none
|road=Cedar Street
|notes=Westbound signage
}}
{{CAint|exit
|mile=5.51
|exit=1D
|road=Glen Cove Road
|notes=
}}
{{CAint|exit
|location=Benicia
|lspan=7
|mile=4.28
|exit=3A
|road=Columbus Parkway
|notes=Serves [[Benicia State Recreation Area]]
}}
{{CAint|exit
|mile=3.51
|exit=3B
|road=Military West
|notes=
}}
{{CAint|exit
|mile=3.32
|exit=4
|road=Southampton Road
|notes=
}}
{{CAint|exit
|mile=1.52
|exit=5
|road=East Second Street&nbsp;– [[Central Benicia, California|Central Benicia]]
|notes=
}}
{{CAint|exit
|mile=1.09
|exit=6
|road=East Fifth Street
|notes=
}}
{{CAint|exit
|mile=0.00
|mspan=2
|exit=7A
|road={{Jct|state=CA|I|680|dir1=north|city1=Fairfield|city2=Sacramento}}
|notes=Eastern terminus; I-680 exit 58A; [[directional T interchange|tri-stack interchange]]
|nspan=2
}}
{{CAint|exit
|mile=none
|exit=7B
|road={{Jct|state=CA|I|680|dir1=south|city1=Martinez|city2=San Jose}}
|notes=none
}}
{{Jctbtm|col=6}}

==See also==
*{{portal-inline|California Roads}}
*{{portal-inline|San Francisco Bay Area}}

==References==
{{Reflist|30em}}

==External links==
{{Attached KML|display=title,inline}}
{{commonscat}}
{{CASR external links|I|780}}
*[http://www.cahighways.org/505-805.html#780 California Highways: Interstate 780]
*[http://www.aaroads.com/california/i-780_ca.html California @ AARoads.com - I-780]

{{3di|80}}

{{Good article}}

[[Category:Interstate Highways in California|80-7]]
[[Category:San Francisco Bay Area freeways|780]]
[[Category:Auxiliary Interstate Highways|80-7]]
[[Category:Interstate 80|7]]
[[Category:Roads in Solano County, California|Interstate 80-7]]