View source for Posey and Webster Street Tubes

{{Short description|Underwater tunnels in California}}
{{Infobox tunnel
|name        = Posey and Webster Street Tubes
|location    = [[Alameda, California]] and [[Oakland, California]]
|coordinates = {{coord|37|47|16|N|122|16|38|W|region:US_type:landmark|display=it}}
|route       = {{jct|state=CA|CA|260}}<br/>(Signed as {{jct|state=CA|CA|61}})
|status      = 
|crosses     = [[Oakland Estuary]]
|start       = North of Wilma Chan Way in Alameda
|end         = South of 6th Street in Oakland
|startwork   = {{start date|1925|06|15}} (Posey)<br/>{{start date|1959|10|12}} (Webster)
|opened = {{start date|1928|10|27}} (Posey)<br/>{{start date|1963|02|13}} (Webster)
|close       = 
|owner       = 
|operator    = [[California Department of Transportation]]
|character   = 
|construction= 
|length      = {{convert|3,545.1 |ft|m}}<ref>{{cite web |last1=Baughn |first1=James |title=Posey Tube |url=https://bridgehunter.com/ca/alameda/bh44814/ |website=Bridgehunter |access-date=19 March 2019}}</ref>
|lanes       = 2 per tube
|speed       = 
|hielevation = 
|lowelevation= 
|height      ={{convert|14.67|ft|m}} (Posey Tube)<br />{{convert|14.83|ft|m}} (Webster St. Tube) 
|width       = 
|grade       = 
|map         = {{maplink|frame=yes|plain=yes|frame-align=center|frame-width=290|zoom=14|type=point}}
}}

The '''Posey''' and '''Webster Street Tubes''' are two parallel underwater tunnels connecting the cities of [[Oakland, California|Oakland]] and [[Alameda, California]], running beneath the [[Oakland Estuary]]. Both are [[immersed tube]]s, constructed by sinking [[precast concrete]] segments to a trench in the Estuary floor, then sealing them together to create a tunnel. The Posey Tube, completed in 1928, currently carries one-way (Oakland-bound) traffic under the Estuary, while the Webster Street Tube, completed in 1963, carries traffic from Oakland to Alameda.

The Posey Tube is the second-oldest underwater vehicular tunnel in the US, preceded only by the [[Holland Tunnel]]. It is the oldest immersed tube vehicular tunnel in the world.

==History==
The [[Oakland Estuary]] (then known as [[Alameda Creek|San Antonio Creek]]) was first crossed by the Webster Street [[swing bridge]] for narrow gauge rail and road traffic, completed in 1871.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DAC18700806.2.27 |title=Oakland Items: Chance for Contractors |date=August 6, 1870 |newspaper=Daily Alta California |access-date=10 September 2020}}</ref><ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=CF18701117.2.12 |title=Where's Alameda? |date=November 17, 1870 |newspaper=The California Farmer |access-date=10 September 2020}}</ref><ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DAC18710412.2.15 |title=Oakland Items: Tax to Pay for Webster-street Drawbridge |date=April 12, 1871 |newspaper=Daily Alta California |access-date=10 September 2020}}</ref> A second crossing was added in 1873 as the Alice Street swing bridge,<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DAC18730406.2.26 |title=Oakland Items: Railroad Improvements |date=April 6, 1873 |newspaper=Daily Alta California |access-date=10 September 2020}}</ref> built for [[Central Pacific Railroad|Central Pacific]] (later [[Southern Pacific Transportation Company|Southern Pacific]]) rail traffic.

Both the Webster and Alice bridges were replaced by new swing bridges completed in 1900 and 1898, respectively. The Alice bridge was replaced by the Harrison Street bridge, one block west.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18980719.2.85.2 |title=The Harrison Street Viaduct a Model |date=July 19, 1898 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref> The replacements were prompted by the [[Secretary of War]], who stated the swing spans each needed to be at least {{convert|150|ft}} to accommodate marine traffic in 1896. At first, it was planned to replace both bridges with a single bridge,<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18961203.2.148 |title=Will Bridge the Creek Together |date=December 3, 1896 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref> but Southern Pacific officials were unable to come to an agreement with Alameda County supervisors, and in 1897 the railroad declared the Harrison Street bridge, replacing the Alice bridge, would be devoted solely to rail traffic, accommodating both narrow and standard-gauge trains.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18970407.2.150 |title=There Will Be Two Bridges |date=April 7, 1897 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref> During the construction of the replacement Webster bridge, county supervisors initially rejected an offer to use the old Alice bridge as a detour for road traffic,<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18980719.2.85.2 |title=Supervisors Decline the Railroad's Offer |date=July 12, 1898 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref> but later accepted, avoiding a more distant route through the eastern part of Alameda,<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18980724.2.143.8 |title=The Alice Street Bridge to be Saved |date=July 24, 1898 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref> and teamster traffic moved to Alice in December.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18981209.2.132 |title=Oakland News Items |date=December 9, 1898 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref> The old Webster bridge was demolished by January 1899.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SFC18990126.2.105 |title=Oakland News Items |date=January 26, 1899 |newspaper=San Francisco Call |access-date=10 September 2020}}</ref>

By 1916, the War Department had declared the replacement Webster and Harrison bridges<ref name=CC-19271222>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=CC19271222.2.33 |title=Oakland and Alameda Soon to Be Linked by Tube Underneath Bay |agency=Associated Press |date=December 22, 1927 |newspaper=Calexico Chronicle |access-date=9 September 2020}}</ref> were a menace to deep-water navigation and an obstacle to continued development of Oakland Harbor in 1916.<ref name=Baker-26/> As an example, {{ship|SS|Lancaster}} rammed the Webster Street bridge in January 1926, causing the swing section to fall into the Estuary and forcing road traffic to be rerouted.<ref>{{cite news |url=https://news.google.com/newspapers?nid=1970&dat=19260108&id=N1YxAAAAIBAJ&pg=1509,622294 |title=Traffic to Alameda Diverted Following Bridge destruction |date=January 8, 1926 |newspaper=Berkeley Daily Gazette |access-date=9 September 2020}}</ref><ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SPDN19260108.2.37 |title=Isthmian Line Freighter Hit Bridge Near Oakland, Knocked Operator and Two Boys Off |date=January 8, 1926 |newspaper=San Pedro Daily News |access-date=10 September 2020}}</ref> The Harrison Street bridge closed to traffic after December 26, 1923 and was largely demolished the following day.<ref>{{cite news |title=Tide is Harnessed to Raze Harrison St. Railroad Bridge |url=https://www.newspapers.com/article/oakland-tribune-tide-is-harnessed-to-raz/137112156/ |access-date=20 December 2023 |newspaper=Oakland Tribune |via=Newspapers.com |date=December 27, 1923 |location=Oakland, California |page=1}} {{free access}}</ref> After the completion of the Posey Tube, the Webster Street bridge was sold to Sacramento County for {{USD|3100|1928|round=-4}} in November 1928.<ref>{{cite news |url=https://www.eastbaytimes.com/2007/04/15/after-fatal-turn-alameda-revamps-bridge/ |url-access=subscription |title=After fatal turn, Alameda revamps bridge |date=April 5, 2007 |newspaper=East Bay Times |access-date=10 September 2020}}</ref> The central swing span was subsequently floated by barge up the [[Sacramento–San Joaquin River Delta|Delta]] and reassembled as part of the new American River Bridge, later known as the [[Jibboom Street Bridge]].<ref>{{Cite news |date=March 1, 1930 |title=Work Begins on New River Bridge |pages=2 |work=The Sacramento Bee}}</ref>

===Posey Tube===
[[File:Posey Tube, Alameda.jpg|upright=1.2|left|thumb|Posey Tube entrance in Alameda]]
Preliminary plans for a tube had been explored as early as 1903, but detailed studies were not prepared until 1922.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=CMPS19490310.2.74.2 |title=Community Forum: What About a Trans-Bay Tube? |date=March 10, 1949 |newspaper=Coronado Compass |access-date=9 September 2020}}</ref> However, the entry of the United States into World War I delayed the plans for a new connection between Oakland and Alameda.<ref name=Baker-26/> A permit for the tube under the Oakland Estuary was granted in April 1923<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SDI19230403.2.8 |title=War Department Gives Alameda Estuary Permit |date=April 3, 1923 |newspaper=Stockton Independent |access-date=11 September 2020}}</ref> and Alameda County voters approved a $5&nbsp;million bond measure in May to build the tube.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SLOTW19230511.2.5 |title=Alameda County Voters Vote for Tube |date=May 11, 1923 |newspaper=San Luis Obispo Tribune |access-date=9 September 2020}}</ref>

After the passage of the bond issue, test borings were taken in the Estuary, and bids were received for the work on March 23, 1925; the construction contract was awarded to the California Bridge and Tunnel Company (CB&TC) with a low bid of {{USD|3882958|1925|round=-4}}, and excavation started from the Oakland end on June 15, 1925. The contract was let by Alameda County without state involvement.<ref name=Baker-26/>

The Posey Tube, completed and opened to traffic on October 27, 1928, was named after [[George Posey]],<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=UCD19251007.2.34 |title=Tube Engineers Cal. Graduates |date=October 7, 1925 |newspaper=California Aggie |access-date=9 September 2020}}</ref> who was the [[Alameda County, California|Alameda County]] Surveyor during the tunnel's planning and construction, and also chief engineer on the construction project.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SN19281026.2.41 |title=Oakland-Alameda Tube Opens |date=October 26, 1928 |newspaper=Sausalito News |access-date=9 September 2020}}</ref><ref name=CEJ-19281212/> It is the first tunnel for road traffic built using the immersed tube technique.<ref>{{cite book |chapter-url=https://books.google.com/books?id=59V5BgAAQBAJ&pg=PA268 |title=Tunnel Engineering Handbook |author=Gursoy, Ahmet |editor1=Kuesel, Thomas R. |editor2=King, Elwyn H. |editor3=Bickel, John O. |date=1996 |chapter=14&nbsp;{{!}}&nbsp;Immersed Tube Tunnels |pages=268–297 |edition=2nd |publisher=Kluwer Academic Publishers |location=Boston, Massachusetts |isbn=978-1-4613-8053-5}}</ref>{{rp|268}} However, the two-lane tube was considered inadequate shortly after its completion. In 1952, the Posey Tube was handling 30,000 to 36,000 cars per day; that same year, [[Coronado, California]], and its mayor Lloyd Harmon contemplated the laying of a similar tunnel to connect Coronado with [[San Diego]], when Alameda mayor [[Frank Osborne (California politician)|Frank Osborne]] wrote a letter to Harmon, which stated <blockquote>from the time it was completed the tube was never adequate for the purpose for which it was built ... I am firmly of the belief that the building of any underwater tube of less than four lanes—two in each direction—would be a serious mistake on the part of any engineers who contemplate it.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=CJ19550127.2.13 |title=Alameda Tunnel Letter of 1952 And Conditions in Alameda Today |date=January 27, 1955 |newspaper=Coronado Eagle and Journal |access-date=9 September 2020}}</ref></blockquote>

===Design===
The ventilation buildings that house the exhaust and fresh air fans are built in an art deco style;<ref>{{Cite news|url=http://www.jacklondonoakland.org/historic_posey_tube_and_renovation_plan|title=Building Spotlight: Historic Posey Tube and 2016 Renovation Plan|work=Jack London Improvement District|access-date=2017-06-12}}</ref> local architect [[Henry H. Meyers]] is credited with the design of both portals.<ref>{{cite web |url=https://oac.cdlib.org/findaid/ark:/13030/tf100001sq/entire_text/ |title=Henry H. Meyers Collection, 1901-1942 |website=Online Archive of California |access-date=10 September 2020}}</ref> The design of the ventilation system to handle toxic vehicular exhaust fumes was modeled on that of the [[Holland Tunnel]]'s ventilation system, and [[Ole Singstad]] (who had designed the pioneering ventilation system of the Holland Tunnel) consulted.<ref name="SSC191202">{{cite book |url=http://archiver.rootsweb.ancestry.com/th/read/NORWAY/2003-05/1051983030 |title=Saga in Steel and Concrete: Norwegian Engineers in America |pages=191–202  |archive-url=https://web.archive.org/web/20150926121051/http://archiver.rootsweb.ancestry.com/th/read/NORWAY/2003-05/1051983030 |archive-date=September 26, 2015 |author=Bjork, Kenneth O. |date=1947 |publisher=Norwegian-American Historical Association}}</ref> A pair of [[Domestic canary|canaries]] were used during construction as [[Sentinel species#Toxic gases|living air monitors]]; although one canary died during construction, it was an accident caused by being penned up with a pet [[cat]] and not a toxic atmosphere.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=MT19280315.2.4 |title=Big Tube Near Completion |agency=United Press |date=March 15, 1928 |newspaper=Madera Tribune |access-date=9 September 2020}}</ref> Up to that time, tunnels had been vented longitudinally, with fresh air blown in one end and out the other; the Holland (and Posey) Tube instead used fans to supply air into the tunnel through a space beneath the roadway, and exhausted air through a similar space above the traffic portion. Ducts were set in the curb and ceiling approximately every {{convert|15|ft}} along the length of the Posey Tube, providing a system of "transverse" ventilation, bottom-to-top rather than end-to-end, ensuring that any fires would not spread through the length of the tunnel.<ref name=UP-1928/>

[[File:Webster Street tube cross-section (typ).svg|thumb|right|Typical section of Webster Street Tube; Posey Tube sections are similar.]]
It was the first precast concrete tube to be constructed, assembled from 12 large segments. The concrete tube was protected from leaks through insulation and coverings applied to the outer surface.<ref name=UP-1928>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=MT19281006.2.42 |title=More Theories Engineers Upset |date=October 6, 1928 |newspaper=Madera Tribune |agency=United Press |access-date=11 September 2020}}</ref> Each segment was cast at [[Hunters Point Naval Shipyard|Hunters Point]] by CB&TC. After they were completed, the segments were sealed and the space beneath the roadway was filled with water as ballast while floating each segment into position; when ready, wet sand was added to the roadway to sink the segment into a dredged underwater trench. Once the joint to the prior segment had been sealed, the water ballast was pumped out and the process was repeated for the next segment.<ref name=CEJ-19281114/>

Including the approaches at each end, the Posey Tube is {{convert|4436|ft}} long;<ref name=CEJ-19281212>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=CJ19281212.2.150 |title=Alameda-Oakland Tube A Success |date=December 12, 1928 |newspaper=Coronado Eagle and Journal |access-date=9 September 2020}}</ref><ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SN19270507.2.57 |title=Oakland Estuary Tube Nears Completion |date=May 7, 1927 |newspaper=Sausalito News |access-date=9 September 2020}}</ref> the tunnel portion itself is {{convert|3545|ft}} long.<ref name=CEJ-19281114>{{cite news |url=https://cdnc.ucr.edu/cgi-bin/cdnc?a=d&d=CJ19281114.2.16 |title=Setting forth merits of the vehicular tube |author=Byron, Wm. C. |date=14 November 1928 |newspaper=Coronado Eagle and Journal |access-date=2 May 2017}}</ref> Each segment is {{convert|203|ft}} long and {{convert|37|ft}} in diameter, and weighs approximately {{convert|5000|ST|t|abbr=on}}.<ref name=CEJ-19281114/> The walls of the tube are {{convert|2+1/2|ft}} thick.<ref name=Baker-26>{{cite magazine |url=https://books.google.com/books?id=2Kg1AAAAIAAJ&pg=PA815 |title=The Oakland-Alameda Estuary Tube: A New Departure in Traffic Tunnel Construction |author=Baker, N.D. |date=December 1926 |pages=815 |magazine=The American City |volume=35 |number=6 |access-date=9 September 2020}}</ref> From Oakland, the approach extends from Sixth Street to Third Street along Harrison Street.<ref name=CEJ-19281114/> The maximum grade within the Posey Tube is 4.59%.<ref name=Baker-26/>

===Webster Street Tube===
[[File:Webster Tube, Oakland.jpg|upright=1.2|left|thumb|Webster Street Tube entrance in Oakland]]
The Webster Street Tube was constructed west of and parallel to the Posey Tube to accommodate increased traffic between Oakland and Alameda and to address the deficiencies of the original design, a single tube with only two lanes. In 1941, "final negotiations" were being made for a second tube,<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=MT19410912.2.28 |title=New Oakland Estuary Tube to Be sought |date=September 12, 1941 |newspaper=Madera Tribune |access-date=10 September 2020}}</ref> and plans for a second tube at Webster Street had been advanced in 1948 as part of a [[Southern Crossing (California)#Parallel Bridge|Parallel Bridge]] scheme. The Parallel Bridge was one of the "Southern Crossing" designs which would have added another trans-Bay bridge south of the 1936 [[San Francisco–Oakland Bay Bridge]].<ref>{{cite magazine |url=https://archive.org/details/californiahighwa194849calirich/page/n231/ |title=Bay Crossings Report |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=27 |number=11–12  |date=November–December 1948 |page=5}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1948_novdec.pdf#page=7 Alternate URL]</ref>

Construction began on October 12, 1959.<ref name=CHPW-60>{{cite magazine |url=https://archive.org/details/cavol3940liforniahigh6061wa00calirich/page/n91 |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=39 |number=3–4 |date=March–April 1960 |pages=11–12;67 |title=Webster St. Tube |author1=Parker, P.E. |author2=Whitlock, H.J.}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1960_marapr.pdf#page=13 Alternate URL]</ref> To prepare the Alameda site, a large Navy hangar was moved; at the time, it set a record for the largest building ever moved.<ref>{{cite magazine |url=https://archive.org/details/cavol3738liforniahighwa195859calirich/page/42/ |title=Record Move  |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=38 |number=11–12  |date=November–December 1959 |pages=42–43}}</ref> The Webster Street Tube was completed and opened to one-way (into Alameda) traffic in 1963.<ref name=CHPW-63>{{cite magazine |url=https://archive.org/details/cvol4142alifornia196263hiwacalirich/page/n531 |title=Webster St. Tube |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=42 |number=3–4  |date=March–April 1963 |pages=10–14 |author1=Names, W.C. |author2=Wolfson, William F.}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1963_marapr.pdf Alternate URL]</ref> Upon completion of the Webster Street Tube, the Posey Tube was closed temporarily and renovations were performed to convert it to one-way (into Oakland) traffic; during renovations, the Webster Street Tube handled bidirectional traffic.<ref name=CHPW-630506/>

Like the preceding Posey Tube, the Webster Street Tube was constructed using immersed precast concrete segments; this time the twelve Webster segments were constructed in a [[graving dock]] built on Alameda. Divers were used to ensure each segment landed in the surveyed location. Piles were driven to support each segment, but the piles were designed to collapse after an additional {{convert|600|ST|t|abbr=on}} of ballast were added, to ensure the segments rested firmly on a bed of packed sand. Construction of the Webster Street Tube started from the Alameda end and progressed towards Oakland, with the precast segments set before additional cast-in-place segments were added at each end.<ref name=CHPW-60/>

Each of the Webster segments were of comparable size and configuration to the earlier Posey Tube segments, measuring {{convert|200|ft}} long and {{convert|37|ft}} in diameter, with walls {{convert|2+1/2|ft}} thick.<ref name=CHPW-60/> However, the Webster segments were equipped with rectangular collars {{convert|45|×|43|ft|abbr=on}} (W×H) at each end, and weighed more, approximately {{convert|5700|ST|t}} each.<ref name=CHPW-61>{{cite magazine |url=https://archive.org/details/cavol3940liforniahigh6061wa00calirich/page/n493/ |title=Tube Report |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=40 |number=1–2  |date=January–February 1961 |pages=25–31 |author1=Greene, George A. |author2=Pomeroy, E.G.}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1961_janfeb.pdf#page=27 Alternate URL]</ref> The roadway within the Webster Street Tube is {{convert|24|ft}} wide, and the minimum vertical clearance is {{convert|15|ft|1+3/8|in|abbr=on}}.<ref name=CHPW-60/> Including approaches, the Webster Street Tube is {{convert|5923|ft}} long,<ref name=CHPW-630506>{{cite magazine |url=https://archive.org/details/cvol4142alifornia196263hiwacalirich/page/n637/ |title=Bay Area Report—1963 |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=42 |number=5–7  |date=May–June 1963 |page=28;32–33 |author1=Sinclair, J.P.}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1963_mayjun.pdf#page=34 Alternate URL]</ref> of which {{convert|3350|ft}} are underwater.<ref name=CHPW-620506>{{cite magazine |url=https://archive.org/details/cvol4142alifornia196263hiwacalirich/page/n187 |title=Bay Area Report |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=41 |number=5–7  |date=May–June 1962 |page=14 |author1=Sinclair, J.P.}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1962_mayjun.pdf#page=16 Alternate URL]</ref>

A novel fluorescent continuous-line lighting system was designed for the Webster Street Tube.<ref>{{cite magazine |url=https://archive.org/details/cavol3738liforniahighwa195859calirich/page/n663/ |title=Tunnel Lighting |author1=Skootsky, Harold |author2=Brass, John R. |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=38 |number=9–10  |date=September–October 1959 |pages=43–46;53}}</ref> Fresh air is supplied through the lower [[lunette]] space beneath the roadway, and exhaust is drawn through the upper lunette space above the tube's false ceiling. Each portal building contains four blowers and four exhaust fans, and they are capable of providing nearly {{convert|1000000|ft3/min|abbr=on}} of airflow in total.<ref name=CHPW-60/> Nearly the entire interior surface of the Webster Street Tube is tiled.<ref>{{cite news |url=https://cdnc.ucr.edu/?a=d&d=OLSF19610814.2.23 |title=Tile Layers 19 Notes |author=Sundahl, Carl |date=August 14, 1961 |newspaper=Organized Labor |access-date=11 September 2020}}</ref>

The Webster Street Tube project cost more than $20&nbsp;million in total,<ref name=CHPW-620506/><ref>{{cite magazine |url=https://archive.org/details/cavol3940liforniahigh6061wa00calirich/page/56/ |title=Bridges |magazine=California Highways and Public Works |publisher=Division of Highways, Department of Public Works, State of California |volume=40 |number=11–12  |date=November–December 1961 |page=56}} [http://libraryarchives.metro.net/DPGTL/Californiahighways/chpw_1961_novdec.pdf#page=58 Alternate URL]</ref> including renovations to the older Posey Tube; the construction contract for Webster was {{USD|17363000|1963|round=-4}} alone.<ref name=CHPW-620506/>

==In media==
* A scene from ''[[THX-1138]]'', the first film directed by [[George Lucas]], was shot in the Tube.<ref>{{cite web |url=https://bampfa.org/event/thx-1138 |title=THX 1138 |publisher=Berkeley Art Museum and Pacific Film Archive |access-date=10 September 2020}}</ref>
* A chase scene of 2003 film [[Matrix Reloaded]] takes place in the Webster Tube.

==References==
{{Reflist}}

===Further reading===
*[https://web.archive.org/web/20060618125542/http://www.alamedainfo.com/Posey_Tube.htm Posey Tube and Webster Street Tube at AlamedaInfo.com by Gary Lenhart] (includes detailed timeline and historical photographs)
* {{citation
|title=Saga in Steel and Concrete: Norwegian Engineers in America
|last=Bjork
|first=Kenneth
|publisher=Norwegian-American Historical Association
|year=1947
|url=http://www.naha.stolaf.edu/
}}
* ''Methods Used in the Construction of Twelve Pre-cast Concrete Segments for the Alameda County, California, Estuary Subway'', in [[American Society of Civil Engineers]], Proceedings, 53 (2) : 2675–2692 (December, 1927)
* S. W. Gibbs,''Construction Methods on Oakland Estuary Tube'', in [[Engineering News Record]], 100:100–105 (January 19, 1928)
* {{cite journal |doi=10.2307/25177536 |author=Lortie, Frank |title=A Monument to Progress: The Posey Tube and the East Bay's Transition to the Age of the Automobile |date=1995 |volume=74 |issue=4 |journal=California History|pages=422–433 |jstor=25177536 }}

==External links==
{{Commons category|Posey and Webster Street Tubes}}
* {{cite web |url=http://collections.museumca.org/?q=taxonomy/term/12349 |title=Posey Tube, photographs |publisher=Oakland Museum of California}}
* ''Building Big'' David Macauley {{ISBN|0-395-96331-1}} A companion to [[PBS]] television series Building Big series PAGES 76–77 explain ventilation system for [[Holland Tunnel]]

{{Crossings navbox
|structure = Crossings
|place = [[Oakland Estuary]]
|bridge = Posey and Webster Street Tubes
|bridge signs = [[File:California 61.svg|20px|State Route 61]]
|upstream text = South
|upstream = [[Park Street Bridge]]
|downstream text = North
|downstream = None
}}
{{Oakland, California}}
{{San Francisco Bay watershed}}
{{Alameda, California}}
{{Bay Area tunnels}}

[[Category:Buildings and structures in Alameda, California]]
[[Category:Art Deco architecture in California]]
[[Category:Buildings and structures in Oakland, California]]
[[Category:San Francisco Bay]]
[[Category:Transportation buildings and structures in Alameda County, California]]
[[Category:Transportation in Oakland, California]]
[[Category:Tunnels in the San Francisco Bay Area]]
[[Category:Tunnels completed in 1928]]
[[Category:Tunnels completed in 1963]]
[[Category:Road tunnels in California]]
[[Category:Immersed tube tunnels in the United States]]
[[Category:San Francisco Bay Trail]]
[[Category:Oakland Designated Landmarks]]