View source for Howrah Bridge

{{Short description|Steel bridge in Kolkata, Kolkata 
, India}}
{{for multi|the films|Howrah Bridge (1958 film)|and|Howrah Bridge (2018 film)|the rock formation|Howrah Natural Bridge}}
{{EngvarB|date=March 2016}} 
{{Use dmy dates|date=March 2016}}
{{Infobox bridge
|name= Howrah Bridge
|image=Howrah bridge at night.jpg
|image_size=275px
|caption=Night view of the Howrah Bridge
| official_name= Rabindra Setu
| named_for = [[Rabindranath Tagore]]
| other_name= 
| native_name = 
| carries= [[Strand Road, Kolkata]],<ref>{{cite web|url=http://www.fodors.com/world/asia/india/kolkata-calcutta/review-110630.html |title=Howrah Bridge Review|access-date=2011-11-21}}</ref><ref>{{cite web|url=http://www.bing.com/mapindia/?FORM=Z9LH3#JndoZXJlMT1ob3dyYWgrYnJpZGdlJmJiPTQwLjMxMzA0MzIwODg4MDklN2UxMTYuNTQyOTY4NzUlN2U1LjYxNTk4NTgxOTE1NTM0JTdlNDIuODkwNjI1|title=Howrah Bridge Map|access-date=2011-11-26}}</ref> Roadway with pedestrians and bicycles
|crosses= [[Hooghly River]]<ref name="NGeo">{{cite journal |author1=Helen Schreider |author2=Frank Schreider |author1-link=Helen and Frank Schreider |author2-link=Helen and Frank Schreider |title=From The Hair Of Siva |journal=[[National Geographic]] |date=October 1960 |volume=118 |issue=4 |pages=445–503}}</ref>
| locale= [[Howrah]], [[Kolkata metropolitan region]], {{flag|India}}
| maint= [[Kolkata Port Trust]]<ref name = "main">{{cite web|url=http://www.howrahbridgekolkata.gov.in/|title=Howrah Bridge Maintenance|access-date=2011-11-21|archive-url=https://web.archive.org/web/20111118055642/http://www.howrahbridgekolkata.gov.in/|archive-date=18 November 2011|url-status=dead}}</ref>
| designer= M/s. Rendel, Palmer and Tritton<ref name="history"/>
| design= [[Suspension bridge|Suspension]] type balanced [[Cantilever bridge|cantilever]]<ref name = "tech">{{cite web|url=http://www.howrahbridgekolkata.gov.in/Bridge_details_middle.htm|title=Bridge Details|access-date=2011-11-21|archive-url=https://web.archive.org/web/20160304002803/http://www.howrahbridgekolkata.gov.in/Bridge_details_middle.htm|archive-date=4 March 2016|url-status=dead}}</ref> and [[Truss arch bridge|truss arch]]<ref name = "struct">{{cite web|url=http://en.structurae.de/structures/data/index.cfm?ID=s0000304|title=Howrah Bridge|access-date=2011-11-21}}</ref>
| builder  = [[Braithwaite, Burn & Jessop Construction Company|The Braithwaite Burn & Jessop Construction Company Limited]]
| mainspan= {{convert|457.2|m|ft|1|abbr=on}}<ref name='tech'/><ref name='struct'/>
| length= {{convert|705|m|ft|1|abbr=on}}<ref name = "roadtraf">{{cite web|url=http://www.roadtraffic-technology.com/projects/howrahbridge/|title=Howrah Bridge|access-date=2011-11-21}}</ref><ref name='mother'/>
| width= {{convert|21.6|m|ft|1|abbr=on}} with two footpaths of {{convert|4.6|m|ft|1|abbr=on}} on either side<ref name='tech'/>
| height= {{convert|82|m|ft|1|abbr=on}}<ref name='struct'/>
| clearance= {{convert|5.8|m|ft|1|abbr=on}}<ref name='tech'/>
| below= {{convert|8.8|m|ft|1|abbr=on}}<ref name='tech'/>
| traffic = Approx. 100,000 vehicles with more than 150,000 pedestrians<ref name='drop'/>
| lanes = 6
| material = Steel
| begin={{date and age|1936}}<ref name='history'/>
| complete={{date and age|1942}}<ref name='history'/>
| open= {{start date and age|df=yes|1943|2|3}}<ref name='mother'/>
| closed=
| toll= No
| mapframe=|coordinates = {{coord|22.5851|88.3469|type;landmark_region:IN|display=inline,title}}
}}

The '''Howrah Bridge''' is a balanced [[steel]] [[bridge]] over the [[Hooghly River]] in [[West Bengal]], India. Commissioned in 1943,<ref name="history">{{cite web|url=http://www.howrahbridgekolkata.gov.in/History_Middle.htm|title=History of the Howrah Bridge|access-date=2011-11-21|archive-url=https://web.archive.org/web/20130413124649/http://www.howrahbridgekolkata.gov.in/History_Middle.htm|archive-date=13 April 2013|url-status=dead}}</ref><ref name="holiday"/> the bridge was originally named the New Howrah Bridge, because it replaced a [[pontoon bridge]] at the same location linking the both sides of cities of Kolkata (Calcutta). Burrabazar is connected with Howrah rail terminal because of this bridge. On 14 June 1965, it was renamed '''Rabindra Setu'''  after the [[Bengali people|Bengali]] poet [[Rabindranath Tagore]], who was the first Indian and Asian [[Nobel Prize in Literature|Nobel laureate]].<ref name="holiday">{{cite web|url=http://www.holidayiq.com/howrah-bridge.php|title=Howrah Bridge – The Bridge without Nuts & Bolts!|access-date=2011-11-21|archive-date=7 January 2019|archive-url=https://web.archive.org/web/20190107062136/http://www.holidayiq.com/howrah-bridge.php%20|url-status=dead}}</ref> It is still popularly known as the Howrah Bridge.

The bridge is one of four on the [[Hooghly River]] and is a famous symbol of [[Kolkata]] and [[West Bengal]]. The other bridges are the [[Vidyasagar Setu]] (popularly called the Second Hooghly Bridge), the [[Vivekananda Setu]] and the relatively new [[Nivedita Setu]]. It carries a daily [[traffic]] of approximately 100,000 vehicles<ref name='traffic'>{{cite web|url=http://www.howrahbridgekolkata.gov.in/Traffic%20Flow.xls|title=Flow of Traffic on an average week day (8AM to 8 PM)|access-date=2011-11-21|archive-url=https://web.archive.org/web/20110818021858/http://howrahbridgekolkata.gov.in/Traffic%20Flow.xls|archive-date=18 August 2011|url-status=dead}}</ref> and possibly more than 150,000 pedestrians,<ref name='drop'>{{cite news|url= https://timesofindia.indiatimes.com/city/kolkata-/Bird-droppings-gnaw-at-Howrah-bridge-frame/articleshow/47808960.cms|archive-url= https://web.archive.org/web/20130616141459/http://articles.timesofindia.indiatimes.com/2003-05-29/kolkata/27281185_1_howrah-bridge-kopt-bird-droppings|url-status= live|archive-date= 16 June 2013|title=Bird droppings gnaw at Howrah bridge frame|access-date=2011-11-21 |work= [[The Times of India]]|date=29 May 2003}}</ref> easily making it the busiest cantilever bridge in the world.<ref name = "hosanna">{{cite web|url=http://www.howrahbridgekolkata.gov.in/Hosanna.htm|title=Hosanna to Howrah Bridge!|access-date=2011-11-21|archive-url=https://web.archive.org/web/20111117054744/http://howrahbridgekolkata.gov.in/Hosanna.htm|archive-date=17 November 2011|url-status=dead}}</ref> The third-longest cantilever bridge at the time of its construction,<ref name='viktor'>{{cite book | author = Victor D. Johnson | title = Essentials Of Bridge Engineering  | year = 2007| publisher = Oxford & Ibh Publishing Co. Pvt Ltd | page = 259}}</ref> the Howrah Bridge is currently the sixth-longest bridge of its type in the world.<ref name="NSBA-longbridge">{{citation|url=http://www.aisc.org/Content/ContentGroups/Documents/NSBA5/20_NSBA_LongestSpans.PDF |archive-url=https://web.archive.org/web/20020601114245/http://www.aisc.org/Content/ContentGroups/Documents/NSBA5/20_NSBA_LongestSpans.PDF |url-status=dead |archive-date=1 June 2002 |title=National Steel Bridge Alliance: World's Longest Bridge Spans |last=Durkee |first=Jackson |publisher=American Institute of Steel Construction, Inc |date=24 May 1999 |access-date=2009-01-02 }}</ref>

[[File:Ferry Howrah Bridge.jpg|thumb|View of a ferry with Rabindra Setu]]

==History==

===1862 proposal by Turnbull===
In 1862, the Government of Bengal asked [[George Turnbull (civil engineer)|George Turnbull]], chief engineer of the [[East Indian Railway Company]], to study the feasibility of bridging the Hooghly River. He had recently established the company's [[Howrah station|rail terminus in Howrah]]. He reported on 19 March, with large-scale drawings and estimates, that:<ref>Diaries of George Turnbull held in Cambridge University, England.</ref>

:* The foundations for a bridge at Calcutta would be at a considerable depth and cost because of the depth of the mud there.
:* The impediment to shipping would be considerable.
:* A good place for the bridge was at Pulta Ghat "about a dozen miles north of Calcutta" where a "bed of stiff clay existed at no great depth under the river bed".
:* A suspended-girder bridge of five spans of {{convert|401|ft|m}} and two spans {{convert|200|ft|m}} would be ideal.

===Pontoon bridge===
[[File:Old Pontoon Bridge.jpg|thumb|left|The old pontoon bridge that was later replaced by the Howrah Bridge]]

In view of the increasing traffic across the Hooghly river, a committee was appointed in 1855–56 to review alternatives for constructing a bridge across it.<ref name = "pontoon">{{cite web|url = http://www.irfca.org/docs/history/howrah-district.html|title=Howrah District (1909)|access-date=2011-11-21}}</ref> The plan was shelved in 1859–60, to be revived in 1868, when it was decided that a bridge should be constructed and a newly appointed trust vested to manage it. The [[Port of Kolkata|Calcutta Port Trust]] was founded in 1870,<ref name='history'/> and the Legislative department of the then Government of Bengal passed the Howrah Bridge Act in the year 1871 under the Bengal Act IX of 1871,<ref name='history'/><ref name='pontoon'/> empowering the lieutenant-governor to have the bridge constructed with Government capital under the aegis of the Port Commissioners.
[[File:Howrah Bridge Act, 1871.jpg|right|thumb|The Howrah Bridge Act of 1871]]

Eventually a contract was signed with [[Bradford Leslie|Sir Bradford Leslie]] to construct a [[pontoon bridge]]. Different parts of the bridge were constructed in England and shipped to Calcutta, where they were assembled. The assembling period was fraught with problems. The bridge was considerably damaged by the great cyclone on 20 March 1874.<ref name='mother'/> A steamer named ''Egeria'' broke from her moorings and collided head-on with the bridge, sinking three pontoons and damaging nearly 200 feet of the bridge.<ref name='mother'/> The bridge was complete in 1874,<ref name='history'/> at a total cost of {{Indian Rupee}}2.2&nbsp;million,<ref name='pontoon'/> and opened to traffic on 17 October of that year.<ref name='mother'>{{cite web|url=https://docs.google.com/viewer?a=v&q=cache:z00ro25q5IIJ:www.riversoftheworld.org/files/11873+bullock+carts+formed+the+eight+-+thirteenths+of+the+vehicular+traffic&hl=en&gl=in&pid=bl&srcid=ADGEESjnc9WzFpJc5rwAmMQrqxcvPWB1X9-uQ5rB53NV2qNioVWIUW-4jGAih7pDzLycPniVaZDN43XMG0op-bU3Ik48lHs3baDe3KIgXYvqCmP7KrESuolsd8tOtPLcWNne69cFC0VX&sig=AHIEtbRyjxcAgfyg3ZjnG9obSGXP8kWzzQ&pli=1|title=River Ganges|access-date=2011-11-21}}</ref> The bridge was then 1528&nbsp;ft long and 62&nbsp;ft wide, with 7-foot wide pavements on either side.<ref name='history'/> Initially the bridge was periodically unfastened to allow steamers and other marine vehicles to pass through. Before 1906, the bridge used to be undone for the passage of vessels during daytime only. Since June of that year it started opening at night for all vessels except ocean steamers, which were required to pass through during daytime.<ref name='pontoon'/> From 19 August 1879, the bridge was illuminated by electric lamp-posts, powered by the dynamo at the Mullick Ghat Pumping Station.<ref name='history'/> As the bridge could not handle the rapidly increasing load, the Port Commissioners started planning in 1905 for a new improved bridge.

===Plans for a new bridge===
In 1906<ref name='mother'/> the Port Commission appointed a committee headed by R.S. Highet, chief engineer, [[East Indian Railway Company|East Indian Railway]] and W.B. MacCabe, chief engineer, Calcutta Corporation. They submitted a report stating that<ref name='history'/>
{{blockquote|Bullock carts formed the eight - thirteenths of the vehicular traffic (as observed on 27 August 1906, the heaviest day's traffic observed in the port of Commissioners 16 days' Census of the vehicular traffic across the existing bridge). The roadway on the existing bridge is 48 feet wide except at the shore spans where it is only 43 feet in roadways, each 21 feet 6 inches wide. The roadway on the new bridge would be wide enough to take at least two lines of vehicular traffic and one line of trams in each direction and two roadways each 30 feet wide, giving a total width of 60 feet of road way which are quite sufficient for this purpose [...] <br> The traffic across the existing floating bridge Calcutta & Howrah is very heavy and it is obvious if the new bridge is to be on the same site as the existing bridge, then unless a temporary bridge is provided, there will be serious interruptions to the traffic while existing bridge is being moved to one side to allow the new bridge to be erected on the same site as the present bridge.}}
The committee considered six options:
# Large ferry steamers capable of carrying vehicular load (set up cost {{Indian Rupee}}900,000, annual cost {{Indian Rupee}}438,000)
# A transporters bridge (set up cost {{Indian Rupee}}2&nbsp;million)
# A tunnel (set up cost {{Indian Rupee}}338.2&nbsp;million, annual maintenance cost {{Indian Rupee}}1,779,000)
# A bridge on piers (set up cost {{Indian Rupee}}22.5&nbsp;million)
# A floating bridge (set up cost {{Indian Rupee}}2,140,000, annual maintenance cost {{Indian Rupee}}200,000)
# An arched bridge
The committee eventually decided on a floating bridge. It extended tenders to 23 firms for its design and construction. Prize money of [[Pound sterling|£]]3,000 ({{Indian Rupee}}45,000, at the then exchange rate) was declared for the firm whose design would be accepted.<ref name='history'/>

===Planning and estimation===
[[File:Howrah Bridge Amendment Act, 1935.jpg|left|thumb|The Howrah Bridge Amendment Act, 1935]]
<!-- Deleted image removed: [[File:Howrah Bridge work site.jpg|left|thumb|Howrah Bridge work site]] -->
The initial construction process of the bridge was stalled due to [[World War I]], although the bridge was partially renewed in 1917 and 1927. In 1921 a committee of engineers named the 'Mukherjee Committee' was formed, headed by [[R. N. Mukherji]], Sir Clement Hindley, chairman of Calcutta Port Trust and J. McGlashan, Chief Engineer. They referred the matter to [[Basil Mott|Sir Basil Mott]], who proposed a single span [[arch bridge]].<ref name='history'/> Charles Alfred O'Grady one of the Engineers

In 1922,  set up, to which the Mukherjee Committee submitted its report. In 1926 the New Howrah Bridge Act passed. In 1930 the Goode Committee was formed, comprising S.W. Goode as president, S.N. Mallick, and W.H. Thompson, to investigate and report on the advisability of constructing a pier bridge between Calcutta and Howrah. Based on their recommendation, M/s. Rendel, Palmer and Tritton were asked to consider the construction of a [[suspension bridge]] of a particular design prepared by their chief draftsman Mr. Walton.<ref name='history'/> On basis of the report, a global tender was floated. The lowest bid came from a German company, but due to increasing political tensions between Germany and Great Britain in 1935, it was not given the contract.<ref name='mother'/> The [[Braithwaite, Burn & Jessop Construction Company|Braithwaite, Burn & Jessop Construction Co.]] was awarded the construction contract that year. The New Howrah Bridge Act was amended in 1935 to reflect this, and construction of the bridge started the next year.<ref name='history'/>

===Construction===
The bridge does not have nuts and bolts,<ref name='holiday'/><ref>{{cite web|url=http://www.mapsofindia.com/kolkata/howrah-bridge.html|title=Howrah Bridge|access-date=2011-11-21|url-status=dead|archive-url=https://web.archive.org/web/20111028120359/http://www.mapsofindia.com/kolkata/howrah-bridge.html|archive-date=28 October 2011|df=dmy-all}}</ref> but was formed by riveting the whole structure. It consumed 26,500 tons of steel, out of which 23,000 tons of high-tensile alloy steel, known as Tiscrom, were supplied by [[Tata Steel]].<ref name='mother'/><ref>{{cite book|author = Kasturi Rangan | title = The Shaping of Indian Science: 1914-1947 | year = 2003| publisher = Universities Press | page = 494}}</ref> The main tower was constructed with single monolith [[Caisson (engineering)|caissons]] of dimensions 55.31{{nbsp}}m{{nbsp}}× 24.8{{nbsp}}m<ref name='tech'/><ref>{{cite book|author=Ponnuswamy|title=Bridge Engineering|year=2007|publisher=Tata Mcgraw Hill Education Private Limited|page=304}}</ref>  with 21 shafts, each 6.25 metre square.<ref name='sing'>{{cite book|author1=William Warren |author2=Luca Invernizzi Tettoni |author3=Luca Invernizzi | title = Singapore, city of gardens | year = 2001| publisher = Periplus Editions | page = 369}}</ref> The Chief Engineer of the Port Trust, Mr. J. McGlashan, wanted to replace the pontoon bridge, with a permanent structure, as the present bridge interfered with north–south river traffic. Work could not be started as World War I (1914–1918) broke out. Then in 1926 a commission under the chairmanship of Sir R. N. Mukherjee recommended a suspension bridge of a particular type to be built across the River Hoogly. The bridge was designed by one Mr. Walton of M/s Rendel, Palmer & Tritton. The order for construction and erection was placed on [[Cleveland Bridge & Engineering Company|M/s.Cleveland Bridge & Engineering Company]] in 1939. Again World War II (1939–1945) intervened. All the steel that was to come from England were diverted for war effort in Europe. Out of 26,000 tons of steel, that was required for the bridge, only 3000 tons were supplied from England. In spite of the Japanese threat, the then (British) government of India pressed on with the construction. Tata Steel were asked to supply the remaining 23,000 tons of high tension steel. The Tatas developed the quality of steel required for the bridge and called it Tiscrom. The entire 23,000 tons was supplied in time. The fabrication and erection work was awarded to a local engineering firm of Howrah: the [[Braithwaite, Burn & Jessop Construction Company|Braithwaite, Burn & Jessop Construction Co.]] The two anchorage caissons were each 16.4 m by 8.2 m, with two wells 4.9 m square. The caissons were so designed that the working chambers within the shafts could be temporarily enclosed by steel diaphragms to allow work under compressed air if required.<ref name='sing'/> The caisson at Kolkata side was set at 31.41 m and that at Howrah side at 26.53 m below ground level.<ref name='tech'/>

One night, during the process of grabbing out the muck to enable the caisson to move, the ground below it yielded, and the entire mass plunged two feet, shaking the ground. The impact of this was so intense that the [[seismograph]] at [[Kidderpore]] registered it as an [[earthquake]] and a [[Hindu]] [[temple]] on the shore was destroyed, although it was subsequently rebuilt.<ref name='tele1'>{{cite news|url=http://www.telegraphindia.com/1080706/jsp/calcutta/story_9501358.jsp|archive-url=https://archive.today/20130203133021/http://www.telegraphindia.com/1080706/jsp/calcutta/story_9501358.jsp|url-status=dead|archive-date=3 February 2013|title=Cat's cradle of steel|access-date=2011-11-21 | location=Calcutta, India|work=The Telegraph|first=Soumitra|last=Das|date=6 July 2008}}</ref> While muck was being cleared, numerous varieties of objects were brought up, including anchors, grappling irons, cannons, cannonballs, brass vessels, and coins dating back to the [[East India Company]].
The job of sinking the caissons was carried out round-the-clock at a rate of a foot or more per day.<ref name="tele1"/>  The caissons were sunk through soft river deposits to a stiff yellow clay 26.5 m below ground level. The accuracy of sinking the huge caissons was exceptionally precise, within 50–75&nbsp;mm of the true position. After penetrating 2.1 m into clay, all shafts were plugged with [[concrete]] after individual dewatering, with some 5 m of backfilling in adjacent shafts.<ref name='sing'/> The main [[pier]]s on the Howrah side were sunk by open wheel [[dredging]], while those on the Kolkata side required compressed air to counter running sand. The air pressure maintained was about 40&nbsp;lbs per square inch (2.8 [[Bar (unit)|bar]]), which required about 500 workers to be employed.<ref name='hosanna'/> Whenever excessively soft soil was encountered, the shafts symmetrical to the caisson axes were left unexcavated to allow strict control. In very stiff clays, a large number of the internal wells were completely undercut, allowing the whole weight of the caisson to be carried by the outside [[Parasitic drag#Skin friction|skin friction]] and the [[Bearing (mechanical)|bearing]] under the external wall. Skin friction on the outside of the monolith walls was estimated at 29&nbsp;kN/m<sup>2</sup> while loads on the cutting edge in clay overlying the founding stratum reached 100 tonnes/m.<ref name='sing'/> The work on the foundation was completed in November 1938.

By the end of 1940, the erection of the cantilevered arms was commenced and was completed in mid-summer of 1941. The two halves of the suspended span, each 282 feet (86 m) long and weighing 2,000 tons, were built in December 1941. The bridge was erected by commencing at the two anchor spans and advancing towards the center, with the use of creeper cranes moving along the upper chord. 16 [[Jack (device)#Hydraulic jack|hydraulic jacks]], each of which had an 800-ton capacity, were pressed into service to join the two halves of the suspended span.<ref name='viktor'/>

The entire project cost {{Indian Rupee}}25 million ([[Pound sterling|£]]2,463,887).<ref name='history'/> The project was a pioneer in bridge construction, particularly in India, but the government did not have a formal opening of the bridge due to fears of attacks by Japanese planes fighting the [[Allies of World War II|Allied Powers]]. Japan had attacked the United States at Pearl Harbor on 7 December 1941. The first vehicle to use the bridge was a solitary [[Calcutta Tramways Company|tram]].<ref name='mother'/>

[[File:Howrah Bus Terminus - Howrah Bridge Area - Howrah 2012-06-22 01350.jpg|thumb|Howrah Bus Terminus, close to Howrah Bridge]]

The bridge is regarded as the "gateway to Kolkata," as it connects the city to Howrah Station.<ref>{{Cite web |last=Naskar |first=Nemai |date=2025-03-10 |title=Howrah Bridge: History, Facts & Best Views |url=https://tripmusing.com/howrah-bridge-history-facts-and-best-views/ |access-date=2025-03-10 |website=Trip Musing}}</ref>

==Description==

===Specifications===
[[File:Howrah-elevation.svg|thumb|Elevation of Rabindra Setu]]

When commissioned in 1943, Howrah was the third-longest cantilever bridge in the world,<ref name='viktor'/> behind [[Quebec Bridge|Pont de Québec]] ({{convert|549|m|ft}}) in Canada and [[Forth Bridge]] ({{convert|521|m|ft}}) in Scotland. It has since been surpassed by three bridges, making it the sixth-longest cantilever bridge in the world in 2013. It is a [[Suspension bridge|suspension type]] [[Cantilever bridge|balanced cantilever]]<ref name = "tech"/> bridge, with a central span {{convert|1,500|ft|m}} between centers of main towers and a suspended span of {{convert|564|ft|m}}. The main towers are {{convert|280|ft|m}} high above the monoliths and {{convert|76|ft|m}} apart at the top. The anchor arms are {{convert|325|ft|m}} each, while the cantilever arms are {{convert|468|ft|m}} each.<ref name = "roadtraf"/> The bridge deck hangs from panel points in the lower chord of the main [[truss]]es with 39 pairs of hangers.<ref name = "tech"/> The roadways beyond the towers are supported from ground, leaving the anchor arms free from deck load. The deck system includes cross girders suspended between the pairs of hangers by a pinned connection.<ref name = "roadtraf"/> Six rows of longitudinal stringer girders are arranged between cross girders. Floor beams are supported transversally on top of the stringers,<ref name = "roadtraf"/> while themselves supporting a continuous pressed steel troughing system surfaced with [[concrete]].<ref name = "tech"/>

The longitudinal expansion and lateral sway movement of the deck are taken care of by expansion and articulation joints. There are two main expansion joints, one at each interface between the suspended span and the cantilever arms and there are others at the towers and at the interface of the steel and concrete structures at both approach.<ref name = "tech"/> There are total of eight [[Articulation (architecture)|articulation joints]], three at each of the cantilever arms and one each in the suspended portion. These joints divide the bridge into segments with vertical pin connection between them to facilitate rotational movements of the deck.<ref name = "tech"/> The bridge deck has longitudinal ruling [[Grade (slope)|gradient]] of 1 in 40 from either end, joined by a vertical curve of radius {{convert|4,000|ft|m}}. The cross gradient of the deck is 1 in 48 between kerbs.<ref name = "tech"/>

===Traffic===
[[File:Howrah Bridge Traffic.jpg|thumb|Bridge traffic]]
[[File:Pedestrians walking on the Howrah Bridge in morning.jpg|thumb|Pedestrians]]
{| class="wikitable" align="right" style="float:right; margin:1em; margin-top:0; text-align:right; font-size:90%"
|-
! style="background:tan;" colspan="4"|<span style="color:black;">Traffic flow for fast moving heavy vehicles<ref name='traffic'/></span>
|-
! Year !! Trams !! Buses/vans !! Trucks
|-
|align=center|1959||align=center|13%||align=center|41%||align=center|46%
|-
|align=center|1986||align=center|4%||align=center|80%||align=center|16%
|-
|align=center|1990||align=center|3%||align=center|82%||align=center|15%
|-
|align=center|1992||align=center|2%||align=center|80%||align=center|18%
|-
|align=center|1999||align=center|-||align=center|89%||align=center|11%
|}
{| class="wikitable" align="right" style="float:right; margin:1em; margin-top:0; text-align:right; font-size:90%"
|-
! style="background:tan;" colspan="3"|<span style="color:black;">Traffic flow for fast moving light vehicles<ref name='traffic'/></span>
|-
! Year !! Two-wheelers/autos !! Cars/taxis
|-
|align=center|1959||align=center|2.47%||align=center|97.53%
|-
|align=center|1986||align=center|24%||align=center|76%
|-
|align=center|1990||align=center|27%||align=center|73%
|-
|align=center|1992||align=center|26%||align=center|74%
|-
|align=center|1999||align=center|20%||align=center|80%
|}
The bridge serves as the gateway to [[Kolkata]], connecting it to the [[Howrah station|Howrah Station]], which is one of the five intercity train terminus stations serving Howrah and Kolkata. As such, it carries the near entirety of the traffic to and from the station, taking its average daily traffic close to nearly 150,000 pedestrians and 100,000 vehicles.<ref name='drop'/> In 1946, a census of the daily traffic was taken, which counted 27,400 vehicles, 121,100 pedestrians and 2,997 cattle.<ref name='hosanna'/>  The bulk of the vehicular traffic comes from buses and cars. Prior to 1993, the bridge also carried trams. [[Calcutta Tramways Company|Trams]] departed from the terminus at Howrah station towards [[Sealdah]], [[Rajabazar, Kolkata|Rajabazar]], [[Shyambazar]], [[Calcutta High Court|High Court]], [[Dalhousie Square]], [[Park Circus]], [[Ballygunge]], and [[Tollygunge]]. In 1993, tram service on the bridge was discontinued due to the increasing load on the structure. However, the bridge still continues to carry much more than the expected load. A 2007 report revealed that nearly 90,000 vehicles were plying on the bridge daily (15,000 of which were goods-carrying), though its load-bearing capacity is only 60,000.<ref name=bridgehistory>{{cite news|url=http://www.ijser.org/researchpaper%5CHowrah-Bridge-and-Second-Hooghly-Bridge-A-Comprehensive-Comparative-Study.pdf|title=Howrah Bridge and Second Hooghly Bridge: A Comprehensive Comparative Study|access-date=2014-11-02 | location=Calcutta, India|date=9 September 2013}}</ref> One of the main reasons for the overloading was that, although vehicles carrying up to 15 tonnes are allowed on the structure, vehicles with 12-18 wheels and carrying loads up to 25 tonnes often plied on it. From 31 May 2007 onwards, overloaded trucks were banned from crossing the bridge and were redirected to the [[Vidyasagar Setu]] instead.<ref>{{cite news|url=http://www.telegraphindia.com/1070414/asp/calcutta/story_7644981.asp|archive-url=https://archive.today/20130203115113/http://www.telegraphindia.com/1070414/asp/calcutta/story_7644981.asp|url-status=dead|archive-date=3 February 2013|title=Howrah bridge ban|access-date=2011-11-21 | location=Calcutta, India|work=The Telegraph|date=14 April 2007}}</ref> The road is flanked by footpaths {{convert|15|ft}} wide, which are thronged with pedestrians.<ref name = "tech"/>

===Maintenance===
[[File:Howrah Bridge-1945 02.jpg|left|thumb|View of Howrah Bridge, {{circa|1945}}]]

The [[Port of Kolkata|Kolkata Port Trust]] (KoPT) is vested with the maintenance of the bridge. The bridge has been subject to damage from vehicles due to rash driving, and corrosion due to atmospheric conditions and biological wastes. In October 2008, 6 high-tech surveillance cameras were placed to monitor the entire {{convert|705|m|ft}} long and {{convert|30|m|ft}} wide structure from the control room. Two of the cameras were placed under the floor of the bridge to track the movement of barges, steamers and boats on the river, while the other four were fixed to the first layer of beams — one at each end and two in the middle — to monitor vehicle movements. This was in response to substantial damage caused to the bridge from collisions with vehicles, so that compensation could be claimed from the miscreants.<ref>{{cite news|url=http://www.telegraphindia.com/1100515/jsp/calcutta/story_12452084.jsp|archive-url=https://archive.today/20130203131329/http://www.telegraphindia.com/1100515/jsp/calcutta/story_12452084.jsp|url-status=dead|archive-date=3 February 2013|title=Bridge bleeds, blow by blow|access-date=2011-11-21 | location=Calcutta, India|work=The Telegraph|first=Sanjay|last=Mandal|date=15 May 2010}}</ref>

Corrosion has been caused by bird droppings and human spitting. An investigation in 2003 revealed that as a result of prolonged chemical reaction caused by continuous collection of bird excreta, several joints and parts of the bridge were damaged.<ref name='drop'/> As an immediate measure, the Kolkata Port Trust engaged contractors to regularly clean the bird droppings, at an annual expense of {{INRconvert|500000}}. In 2004, KoPT spent {{INRconvert|6.5|m}} to paint the entirety of {{convert|2.2|e6m2|e6sqft|abbr=off}} of the bridge. Two coats of [[aluminium]] paint, with a primer of [[zinc chromate]] before that, was applied on the bridge, requiring a total of 26,500 litres of paint.<ref>{{cite news|url=http://www.telegraphindia.com/1040917/asp/calcutta/story_3767191.asp|archive-url=https://archive.today/20130203134259/http://www.telegraphindia.com/1040917/asp/calcutta/story_3767191.asp|url-status=dead|archive-date=3 February 2013|title=Calcutta icon, painted and lit- October makeover for Howrah bridge |access-date=2011-11-21 |location=Calcutta, India |work=The Telegraph |first=Swati |last=Sengupta |date=17 September 2004}}</ref>

[[File:Image-Kolkata Bridge.jpg|right|thumb|The illuminated Howrah Bridge at night]]

The bridge is also considerably damaged by pedestrians [[saliva|spitting]] out acidic, [[slaked lime|lime]]-mixed stimulants ([[gutka]] and [[paan]]).<ref name="spitgaurdian">{{cite news|url=https://www.theguardian.com/world/2010/may/26/spit-threatens-indian-bridge|title=Spit threatens Indian bridge|last=Burke|first=jason|date=26 May 2010|work=[[The Guardian]]|access-date=7 May 2012|location=New Delhi}}</ref> A technical inspection by Port Trust officials in 2011 revealed that spitting had reduced the thickness of the steel hoods protecting the pillars from six to less than three millimeters since 2007.<ref name="schemetosave">{{cite news|url=https://www.bbc.co.uk/news/world-asia-india-15837262|title=Scheme to save Calcutta's Howrah Bridge from spit|last=Bhattasali|first=Amitabha|date=23 November 2011|publisher=[[BBC News]]|access-date=7 May 2012|location=Kolkata}}</ref><ref>{{cite web|url=http://www.paintsquare.com/news/?fuseaction=view&id=4896|title=Spit Threatens Busy Calcutta Bridge|access-date=2011-11-21}}</ref> The hangers need those hoods at the base to prevent water seeping into the junction of the cross-girders and hangers, and damage to the hoods can jeopardize the safety of the bridge. KoPT announced that it will spend {{INRconvert|2|m}} on covering the base of the steel pillars with [[Fiberglass|fibreglass]] casing to prevent spit from corroding them.<ref>{{cite news|url=http://www.telegraphindia.com/1111114/jsp/calcutta/story_14744558.jsp|archive-url=https://archive.today/20130203175020/http://www.telegraphindia.com/1111114/jsp/calcutta/story_14744558.jsp|url-status=dead|archive-date=3 February 2013|title=Extra cover for spittoon bridge|access-date=2011-11-21 | location=Calcutta, India|work=The Telegraph|first=Sanjay|last=Mandal|date=14 November 2011}}</ref>

On 24 June 2005, a private [[cargo vessel]] ''M V Mani'', belonging to the Ganges Water Transport Pvt. Ltd, while trying to pass under the bridge during high tide, had its [[funnel (ship)|funnel]] stuck underneath for three hours, causing substantial damage worth about {{Indian Rupee}}15&nbsp;million to the stringer and longitudinal girder of the bridge.<ref>{{cite news|url=https://timesofindia.indiatimes.com/india/Howrahs-first-Ship-stuck-under/articleshow/1151756.cms|archive-url=https://web.archive.org/web/20130616152519/http://articles.timesofindia.indiatimes.com/2005-06-24/india/27852682_1_howrah-bridge-howrah-side-high-tide|url-status=live|archive-date=16 June 2013|title=Howrah's first: Ship stuck under|access-date=2011-11-21 |work=[[The Times of India]]|date=24 June 2005}}</ref> Some of the 40 cross-girders were also broken. Two of four trolley guides, bolted and welded with the girders, were extensively damaged. Nearly {{convert|350|m|ft}} of {{convert|700|m|ft}} of the track were twisted beyond repair.<ref>{{cite web|url=http://howrahbridgekolkata.nic.in/Bridge_accident_17_06_05.htm|title=A BARGE RAMS INTO THE BRIDGE IN A RARE ACCIDENT|access-date=2011-11-21|archive-date=26 April 2012|archive-url=https://web.archive.org/web/20120426000716/http://howrahbridgekolkata.nic.in/Bridge_accident_17_06_05.htm|url-status=dead}}</ref> The damage was so severe that KoPT requested help from Rendall-Palmer & Tritton Limited, the original consultant on the bridge from UK. KoPT also contacted [[Steel Authority of India Limited|SAIL]] for 'matching steel' used during its construction in 1943.<ref>{{Cite web |url=http://news.outlookindia.com/items.aspx?artid=306668 |title=British consultants contacted for repair of Howrah Bridge &#124; news.outlookindia.com |access-date=13 September 2012 |archive-url=https://web.archive.org/web/20130602165517/http://news.outlookindia.com/items.aspx?artid=306668 |archive-date=2 June 2013 |url-status=dead }}</ref> For the repair, which cost around {{INRconvert|5|m}}, about 8 tonnes of steel was used. The repairs were completed in early 2006.<ref>{{cite news| url=http://www.telegraphindia.com/1060102/asp/calcutta/story_5659408.asp| archive-url=https://archive.today/20130203182159/http://www.telegraphindia.com/1060102/asp/calcutta/story_5659408.asp| url-status=dead| archive-date=3 February 2013| location=Calcutta, India| work=The Telegraph| first=Sanjay| last=Mandal |title=Bridge under barge stress| date=2 January 2006}}</ref>

==Cultural significance==
[[File:Howrah Bridge 02.jpg|thumb|Pedestrians on the bridge]]
[[File:The Howrah Bridge as seen from Howrah bus stand beside MG Road.jpg|thumb|Howrah Bridge as seen from Howrah]]

The bridge has been shown in numerous films, such as [[Bimal Roy]]'s 1953 film {{Lang|hi-latn|[[Do Bigha Zamin]]}}, [[Ritwik Ghatak]]'s ''[[Bari Theke Paliye]]'' in 1958, [[Satyajit Ray]]'s ''[[Parash Pathar]]'' in the same year, [[Mrinal Sen]]'s ''[[Neel Akasher Neechey]]'' in 1959, [[Shakti Samanta]]'s ''[[Howrah Bridge (film)|Howrah Bridge]]'' (1958), that featured the famous song [[Mera Naam Chin Chin Chu]] and ''[[China Town (1962 film)|China Town]]'' (1962) and ''[[Amar Prem]]'' (1971), Amar Jeet's 1965 ''[[Teen Devian]]'' in 1965, [[Mrinal Sen]]'s 1972 [[National Film Award for Second Best Feature Film|National Award]] winning [[Cinema of West Bengal|Bengali]] film ''[[Calcutta 71]]'' and Sen's Calcutta Trilogy its sequel in 1973, ''[[Padatik (1973 film)|Padatik]]'', [[Richard Attenborough]]'s 1982 [[Academy Award for Best Picture|Academy Award]] winning film ''[[Gandhi (film)|Gandhi]]'', [[Goutam Ghose]]'s 1984 Hindi film ''[[Paar (film)|Paar]]'', [[Raj Kapoor]]'s  ''[[Ram Teri Ganga Maili]]'' in 1985, [[Nicolas Klotz]]'s ''[[The Bengali Night]]'' in 1988, [[Roland Joffé]]'s [[Cinema of the United States|English language]] film ''[[City of Joy (film)|City of Joy]]'' in 1992, [[Florian Gallenberger]]'s [[Bengali language|Bengali]] film ''[[Shadows of Time]]'' in 2004, [[Mani Ratnam]]'s Bollywood film ''[[Yuva]]'' in 2004, [[Pradeep Sarkar]]'s 2005 Bollywood film ''[[Parineeta (2005 film)|Parineeta]]'', [[Subhrajit Mitra]]'s 2008 Bengali film ''[[Mon Amour: Shesher Kobita Revisited]]'', [[Mira Nair]]'s 2006 film ''[[The Namesake (film)|The Namesake]]'', [[Blessy]]'s 2008 Malayalam Film ''[[Calcutta News (film)|Calcutta News]]'', [[Surya Sivakumar]]'s 2009 Tamil film ''[[Aadhavan]]'', [[Imtiaz Ali (director)|Imtiaz Ali]]'s 2009 Hindi film ''[[Love Aaj Kal (2009 film)|Love Aaj Kal]]'', [[Abhik Mukhopadhyay]]'s 2010 Bengali film ''[[Ekti Tarar Khonje]]'', [[Sujoy Ghosh]]'s 2012 Bollywood film ''[[Kahaani]]'', [[Anurag Basu]]'s 2012 Hindi film ''[[Barfi!]]'', [[Riingo Banerjee]]'s 2012 Bengali film ''[[Na Hannyate]]'', Rana Basu's 2013 Bengali film ''[[Namte Namte]]'', and [[Ali Abbas Zafar]]'s 2014 Hindi film ''[[Gunday]],'' 2015 YRF release from director [[Dibakar Banerjee]]'s ''[[Detective Byomkesh Bakshy!]]'', and even the 2024 Hindi hit ''[[Bhool Bhulaiyaa 3]]''. [[Shoojit Sircar]]'s ''[[Piku]]'' also features some scenes on this iconic bridge. The bridge was also featured in [[Garth Davis]]' Academy Award-nominated 2016 film ''[[Lion (2016 film)|Lion]]''. [[Anvita Dutt]]'s 2022 movie ''[[Qala (film)|Qala]]'' features some fictional scenes of the bridge's construction.

==See also==
* [[List of largest cantilever bridges]]
*[[List of longest bridges above water in India]]

==References==
{{reflist}}

==External links==
{{commons category|Howrah Bridge}}
{{wikimedia}}
{{refbegin}}
*[https://web.archive.org/web/20050829161819/http://www.howrahbridgekolkata.nic.in/ Official Website of Howrah Bridge, maintained by Calcutta Port Trust]
*[https://web.archive.org/web/20060603031057/http://www.kolkataweb.com/picture/picdisplay.php?id=226 Picture of old Howrah Bridge]
*[http://kulxp.blogspot.com/2006/03/my-kolkata-2.html Photos of Howrah Bridge]
*{{IndiaArchive|handle=2748047|identifier=PR_000004001277|year=1871|title=Howrah Bridge}}
{{refend}}

{{Bridges in India}}
{{Kolkata topics}}
{{Howrah topics}}

[[Category:1943 establishments in India]]
[[Category:Bridges completed in 1874]]
[[Category:Bridges completed in 1943]]
[[Category:Bridges in Kolkata]]
[[Category:Buildings and structures in Howrah district]]
[[Category:Cantilever bridges]]
[[Category:Buildings and structures in Howrah]]
[[Category:Pontoon bridges]]
[[Category:Tourist attractions in Howrah]]
[[Category:Transport in Howrah]]
[[Category:Transport in Kolkata]]
[[Category:Bridges in West Bengal]]
[[Category:20th-century architecture in India]]
[[Category:Howrah Bridge]]