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.

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.

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.

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.

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.

Source…www.the betterindia.com

Natarajan