Thursday, 8 February 2018

Howrah Bridge - 75th anniversary - amazing facts of a heritage structure built by the British


Horah bridge, Kolkata..bbjconst.com/f
Howrah Bridge in Kolkata, West Bengal  over the Hooghly River linking the two cities of Howrah and Kolkata is an indispensable life line of both  busy cities.  What is the Golden Gate Bridge to the people of San Francisco and what is the Brooklyn Bridge to New Yorkers, the Howrah Bridge is to  the people of Kolkata. It is yet another British legacy that has left a permanent mark in this vast City that was once the capital of  British India. Believe it or not, it is the busiest cantilever bridge in the world and the earliest among the  four  bridges on the Hooghly River.

The following are the amazing facts of Howrah bridge:

01. Howrah Bridge was Commissioned on the night of February 1943 with no pomp and show, replacing the old  pontoon bridge (1874)  that was built earlier by Sir. Bradford Leslie in 1874 after then Government of Bengal passed the Howrah Bridge Act  under the Bengal Act IX of 1871. The old pontoon bridge  could not accommodate more loads, hence, a better, improved bridge became the need of the hour. The first vehicle to use the new bridge was a solitary tram because of fear of air raids by Japanese  which  sided with Allied Forces. 

Japanese bombing of Kolkata 1942-thebetterindia.com/
Above image:  A total of  131 bombs were dropped on the 10th, 16th and 28th of December 1942 and 17th and 23rd of January 1943. The attack on 23rd was the most serious one . More than  70 bombs  were dropped over the dock area of Calcutta and the casualty on that day was nearly 500.


02. So, KPT authorized  the Lieut. Governor to have a  bridge built  with Government capital under the supervision of the Port Commissioners (who also acted as Bridge Commissioners).

03. It took a while to take steps on the new bridge because of interruption of WWI, selection of new site, etc. In 1926, the New Howrah Bridge Act was passed. In 1930 the Goode Committee was formed, comprising S.W. Goode as President to report on the construction of pier bridge between  Howrah and Kolkata. 

04. The  suspension bridge designed by one Mr. Walton of M/s Rendel, Palmer & Triton was finally selected by the committee.

05. As for the contract work, despite the raging world war II, a global tender was invited.  A German firm - Krupps made the lowest bid, but was rejected by the  British India government because of belligerent attitude of Germany.  The British firm Braithwaite, Burn & Jessop Construction Co., was  given the construction contract that year. The order for construction and erection was awarded to M/s.Cleveland Bridge & Engineering Company in 1939.

06. The unique feature of this bridge is it does not have nuts and bolts, but was firmly held together  by riveting the whole structure. The bridge  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 from their works; only 3000 tons were supplied from England. Normally any bridge sways in the wind. But, 

Howrah bridge, Kolkata. Expedia
the Howrah Bridge has special expansion and articulation joints, to compensate for turbulence.


07. Because of WWII (1939 - 1945) the steel that was to come from England was diverted for war effort in Europe. Further the British India  government, it is said, had shipped to Europe the  steel rails in the railway yard.  In spite of the Japanese threat, the then (British) government of India kept the bridge construction work going. The city had been bombed by Japanese in 1942. The construction began in 1936 and completed in 1942.

08. The bridge carries heavy vehicular traffic - daily  roughly 100,000 vehicles and possibly more than 150,000 pedestrians pass through this bridge.Total length of the bridge 705 meters; height 82 meters;  Longest span 1500 feet.

09.  When commissioned in 1943, Howrah was the 3rd-longest cantilever bridge in the world, behind Pont de Québec (549 metres (1,801 ft)) in Canada and Forth Bridge (521 metres (1,709 ft)) in Scotland:  currently the sixth-longest bridge of its type in the world. It is a suspension type balanced cantilever bridge with the central span between two large towers of the bridge measuring  roughly 1500 feet. Each of the  anchor  arms measures about 325 feet, whereas the cantilever arms measure about 468 feet each.
Howrah bridge, Kolkata, W.Bengal. rediff.com
10. It requires not less than 26500 liters of aluminium paint to do the painting job on the bridge, covering 24 million sq. feet.
11. The bridge was not free from accident. In 2005 a privately owned  cargo vessel' funnel struck part of the bridge that caused severe damage with 40 cross girders broken  and 350 meters of track were twisted. The original consultant firm Rendel, Palmer and Triton  Ltd, UK was of great help. The KPT had to shell out roughly Rs. two million to fix the steel pillars as the thickness of the steel was corroded by  spitting of chewing tobacco - a lousy civic problem found across India, in particular, in the delta districts of Tamil Nadu. 

12. Unlike many states in India where the bridges, etc., come under the PW department, here the Howrah bridge is being maintained by the KPT.
During the 1942 Japanese bombing, one of the bombs dropped close to the massive steel structure. It is kept in the Kolkata Police Museum at Malicktala. 

13. The KPT has a plan to build a shed over the pedestrian pathway to shelter the people from rain and hot Sun without spoiling  the beauty of this heritage structure.

https://en.wikipedia.org/wiki/Howrah_Bridge

https://www.thebetterindia.com/130211/howrah-bridge-75-years-kolkata/





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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 newly built Nivedita Setu. It weathers the storms of the Bay of Bengal region, carrying a daily traffic of approximately 100,000 vehicles[11] and possibly more than 150,000 pedestrians,[9] easily making it the busiest cantilever bridge in the world.[12] The third-longest cantilever bridge at the time of its construction,[13] the Howrah Bridge is currently the sixth-longest bridge of its type in the world.[14]


1862 proposal by Turnbull

In 1862, the Government of Bengal asked 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 rail terminus in Howrah. He reported on 19 March, with large-scale drawings and estimates, that:[15]

    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 400 feet (120 m) and two spans 200 feet (61 m) would be ideal.

The bridge was not built.
Pontoon bridge
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.[16] 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 Calcutta Port Trust was founded in 1870,[8] 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,[8][16] empowering the Lieutenant-Governor to have the bridge constructed with Government capital under the aegis of the Port Commissioners.
The Howrah Bridge Act of 1871

Eventually a contract was signed with Sir Bradford Leslie to construct a pontoon bridge. Different parts 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.[7] 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.[7] The bridge was completed in 1874,[8] at a total cost of ₹2.2 million,[16] and opened to traffic on 17 October of that year.[7] The bridge was then 1528 ft. long and 62 ft. wide, with 7-foot wide pavements on either side.[8] 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.[16] From 19 August 1879, the bridge was illuminated by electric lamp-posts, powered by the dynamo at the Mullick Ghat Pumping Station.[8] 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[7] the Port Commission appointed a committee headed by R.S. Highet, Chief Engineer, East Indian Railway and W.B. MacCabe, Chief Engineer, Calcutta Corporation. They submitted a report stating that[8]

    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 [...]
    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 ₹900,000, annual cost ₹437,000)
    A transporters bridge (set up cost ₹2 million)
    A tunnel (set up cost ₹338.2 million, annual maintenance cost ₹1779,000)
    A bridge on piers (set up cost ₹22.5 million)
    A floating bridge (set up cost ₹2140,000, annual maintenance cost ₹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 £ 3,000 (₹45,000, at the then exchange rate) was declared for the firm whose design would be accepted.[8]
Planning and estimation
The Howrah Bridge Amendment Act, 1935

The initial construction process of the bridge was stalled due to the 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 Sir R.N. Mukherjee, Sir Clement Hindley, Chairman of Calcutta Port Trust and J. McGlashan, Chief Engineer. They referred the matter to Sir Basil Mott, who proposed a single span arch bridge.[8] Charles Alfred O"Grady one of the Engineers

In 1922 the New Howrah Bridge Commission was 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.[8] 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.[7] The 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.[8]
Construction

The bridge does not have nuts and bolts,[10][17] 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.[7][18] The main tower was constructed with single monolith caissons of dimensions 55.31 x 24.8 m[4][19] with 21 shafts, each 6.25 metre square.[20] 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 & Triton. The order for construction and erection was placed on 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 Tiscom. 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 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.[20] The caisson at Kolkata side was set at 31.41 m and that at Howrah side at 26.53 m below ground level.[4]

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.[21] 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.[21] 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 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.[20] The main piers 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 lbs per square inch (2.8 bar), which required about 500 workers to be employed.[12] 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 skin friction and the bearing under the external wall. Skin friction on the outside of the monolith walls was estimated at 29 kN/m2 while loads on the cutting edge in clay overlying the founding stratum reached 100 tonnes/m.[20] The work on the foundation was completed on 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 hydraulic jacks, each of which had an 800-ton capacity, were pressed into service to join the two halves of the suspended span.[13]

The entire project cost ₹25 million (£2,463,887).[8] 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 Allied Powers. Japan had attacked the United States at Pearl Harbor on December 7, 1941. The first vehicle to use the bridge was a solitary tram.[7]

The bridge is regarded "the gateway to Kolkata, as it connects the city to the Howrah Station".[22]
Description
Specifications
Elevation of Howrah bridge

When commissioned in 1943, Howrah was the 3rd-longest cantilever bridge in the world,[13] behind Pont de Québec (549 metres (1,801 ft)) in Canada and Forth Bridge (521 metres (1,709 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 type balanced cantilever[4] bridge, with a central span 1,500 feet (460 m) between centers of main towers and a suspended span of 564 feet (172 m). The main towers are 280 feet (85 m) high above the monoliths and 76 feet (23 m) apart at the top. The anchor arms are 325 feet (99 m) each, while the cantilever arms are 468 feet (143 m) each.[6] The bridge deck hangs from panel points in the lower chord of the main trusses with 39 pairs of hangers.[4] 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.[6] Six rows of longitudinal stringer girders are arranged between cross girders. Floor beams are supported transversally on top of the stringers,[6] while themselves supporting a continuous pressed steel troughing system surfaced with concrete.[4]

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.[4] There are total 8 articulation joints, 3 at each of the cantilever arms and 1 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.[4] The bridge deck has longitudinal ruling gradient of 1 in 40 from either end, joined by a vertical curve of radius 4,000 feet (1,200 m). The cross gradient of deck is 1 in 48 between kerbs.[4]
Traffic
Bridge traffic
Traffic Flow for fast moving heavy vehicles[11]
Year     Trams     Buses/Vans     Trucks
1959     13%     41%     46%
1986     4%     80%     16%
1990     3%     82%     15%
1992     2%     80%     18%
1999     -     89%     11%
Traffic Flow for fast moving light vehicles[11]
Year     Two-wheelers/Autos     Cars/Taxis
1959     2.47%     97.53%
1986     24%     76%
1990     27%     73%
1992     26%     74%
1999     20%     80%

The bridge serves as the gateway to Kolkata, connecting it to the Howrah Station, which is one of the four intercity train 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.[9] In 1946 a census was taken to take a count of the daily traffic, it amounted to 27,400 vehicles, 121,100 pedestrians and 2,997 cattle.[12] The bulk of the vehicular traffic comes from buses and cars. Prior to 1993 the bridge used to carry trams also. Trams departed from the terminus at Howrah station towards Rajabazar, Sealdah, High Court, Dalhousie Square, Park Circus and Shyambazar. From 1993 the tram services on the bridge were discontinued due to increasing load on the bridge. 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.[23] One of the main reasons of overloading was that although vehicles carrying up to 15 tonnes are allowed on the structure, vehicles with 12-18 wheels and carrying load up to 25 tonnes often plied on it. 31 May 2007 onwards, overloaded trucks were banned from plying on the bridge, and were redirected to the Vidyasagar Setu instead.[24] The road is flanked by footpaths of width 15 feet, and they swarm with pedestrians.[4]


https://en.wikipedia.org/wiki/Howrah_Bridge
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 by Rayomand Engineer
February 6, 2018, 6:58 pm

In 1946, a census was conducted to count the daily traffic footfall on the state-of-the-art Howrah Bridge. The figures registered were 27,400 vehicles, 121,100 pedestrians and 2,997 cattle.

Contrast the above information with a 2007 report, which showed a daily flow of 90,000 vehicles, out of which 15,000 were goods vehicles.
The iconic bridge in the world is regarded as the “Gateway to Kolkata” since it connects the city to Howrah, and turned 75, this February. Of course, the bullock-carts of yesteryears have been replaced with high-end luxury cars.
The iconic Howrah Bridge, standing tall for decades.Image Courtesy: Flickr.
The iconic Howrah Bridge, standing tall for decades.Image Courtesy: Flickr.

Apart from being a pathway for various modes of transport, this iconic suspension-type balanced cantilever bridge has been the backdrop of many intense film scenes. Remember Ajay Devgn getting gunned down while riding a bike down the bridge in Yuva, or the dramatic Durga Puja celebrations under the bridge, as depicted in Gunday?

Many movie scenes used the bridge in the backdrop, starting with Bimal Roy’s 1953 classic Do Bigha Zameen, to Garth Davis’ Academy Award-nominated 2016 film Lion.

The Howrah Bridge made quite the impact before it was fully constructed. One night, during construction, workers were removing muck, trying to fix a cassion. The entire mass plunged 2 feet, and the ground shook. The intense impact caused a seismograph at Kidderpore, to register an earthquake. Interestingly once the muck cleared, many interesting objects of value, like anchors, cannons, cannon-balls, brass vessels, and coins dating back to the era of the East India Company were found.
Commissioned in 1943, the Howrah Bridge had a quiet opening. Even though it was a pioneering construction, a behemoth much ahead of its time, the Government decided to play things down, due to the fear of a Japanese air attack, since World War II was raging during that time.
Japanese war planes were a threat to the Howrah Bridge, during World War II. Image Courtesy: MaxPixel.
Japanese war planes were a threat to the Howrah Bridge, during World War II. Image Courtesy: MaxPixel.

A gigantic technical marvel, ahead of its time

One unique feature of this enormous bridge is that no nuts and bolts have been used in its construction. The steel fabrication has been riveted into place to hold the entire span of the bridge over the river Hooghly.

26,500 tonnes of steel, mostly supplied by Tata Steel, single monolith caissons of dimensions 55.31 x 24.8 metres, with 21 shafts, each 6.25-metre square, and sixteen 800-tonne capacity hydraulic jacks, amongst other materials, were used in the construction of the bridge.

Walk along the bridge’s massive length, and you will feel dwarfed and insignificant, for a good reason. The structure has a central span of 1,500 feet between centres of main towers and a suspended span of 564 feet. The main towers are 280 feet high above the monoliths and 76 feet apart at the top. The anchor arms are 325 feet each, while the cantilever arms are 468 feet each.

The bridge deck hangs from panel points in the lower chord of the main trusses with 39 pairs of hangers. There are cross girders, stringer girders, and floor beams that complete the intricate construction. Any bridge sways in the wind. The Howrah Bridge has special expansion and articulation joints, to compensate for turbulence.

A mammoth maintenance routine

Naturally, a structure this huge, serving as a roadway to so much transport, needs to be kept at its optimum condition. You’d think that the bridge would need a natural disaster to shake its foundations, but regular daily life puts a strain on the structure.

The maintenance of this gargantuan bridge is no easy task. Just ask the Kolkata Port Trust, which, post a 2003 investigation, spent Rs 5,00,000 annually, just to clean the bird droppings that were corroding joints and other parts of the bridge. In 2004, it cost Rs 6.5 million, to paint the 24 million square feet of the bridge, using 26,500 litres of aluminium paint and zinc chromate primers.

A cultural icon that would not be here today

We might not have had the same Howrah Bridge, if it ironically, weren’t for World War II. Before its construction, a global tender was floated, and a German company turned out to be the lowest bidder. Increasing hostilities in 1935 resulted in the German contract being cancelled, with the tender going to India’s Braithwaite Burn and Jessop Construction Company Limited.

The same war, which saw the bridge come to life, also threatened to destroy it. While the war was in full swing, India found herself in the position of a de-facto ally to Britain and the Western Allied Powers. Naturally the Japanese, part of the opposition, bombed Kolkata from 1942 to 1944, trying to destroy the bridge, and operations at the seaport. The British responded swiftly, even turning Kolkata’s Red Road, into a runway for Spitfires to take off.

The quiet hero during this time of crisis was the 978 Balloon Squadron. The British set up balloons, attached to the ground by several steel cables. These balloons prevented bombers from going low and hitting targets. The planes would get stuck in the cables and crash. The Japanese Air Force flew many sorties over Kolkata, bombing the central business district and the docks.
As many as 131 bombs were dropped on the 10th, 16th and 28th of December 1942 and 17th and 23rd of January 1943. The attack on 23rd was the most devastating with over 70 bombs being dropped over the dock area and the casualty on that day was nearly 500.
Many areas of Kolkata were bombed during World War II. Representative image only. Image Courtesy: Wikipedia.
Many areas of Kolkata were bombed during World War II. Representative image only. Image Courtesy: Wikipedia.

Let us appreciate this giant superstructure, which has stood tall for aeons.

Unfortunately, today, the most significant threat the iconic Howrah Bridge faces isn’t from Japanese fighter planes or their bombs, but from corrosive spit containing tobacco, pan-masala and other acidic, poisonous ingredients.

A 2011 inspection by Kolkata Port Trust authorities, calculated the damage—a total of Rs 2 million had to be spent, to cover parts of the bridge with fibreglass, to avoid corrosion due to spitting.

Spitting remains the biggest threat to this bridge, and a 2013 report in The Guardian mentions the bridge’s Chief Engineer, AK Mehra, who said that the slaked lime and paraffin in the poisonous spit are highly corrosive. In some areas, the steel pillars have been damaged by as much as 60 percent.

You may also like: India’s First Under-River Tunnel Set to Connect Kolkata and Howrah Very Soon!

During World War II, when Kolkata was under attack, worried citizens, with a bag full of Vaseline, and bandages, would run to air-raid shelters, after safely hiding their earthen jars which contained their drinking water supply.

Those citizens if alive today, would surely be surprised when they realise the iconic Howrah Bridge which survived the Japanese bombing might not survive the Indian habit of spitting.

https://www.thebetterindia.com/130211/howrah-bridge-75-years-kolkata/