Howrah Bridge, located in Kolkata,  India, is a cantilever bridge that spans over Hooghly River. Built during the British rule, in 1943, it is one of the most famous symbols of Kolkata.

The nearly 70-year-old bridge however, is in danger of collapsing, not from age, but from human saliva. It is common to find many locals chewing paan (a mild intoxicant containing betel nuts and leaves), and then spitting out red-tinged saliva on the steel hangers of the bridge. This is not only unsightly, but the corrosion caused by the accumulation of several years worth of saliva, is a cause of serious concern. Bird droppings are also a major cause for the corrosion of the bridge, and regular cleaning was undertaken ever since this threat was identified. The cleaning is apparently not good enough to work its way through the layers of spit and local authorities say the corrosion has caused so much damage that the thickness of the hangers has reduced to half of the original, from 6mm to 3mm.

Photo: Deshakalyan Chowdhury/AFP

Efforts are being made to salvage this old Indian monument from disgrace. Engineers have come up with an idea to cover the steel with sheets of fiberglass. There are other factors that are a cause for concern in the maintenance of the bridge, such as damage from vehicles due to rash driving. Over 100,000 vehicles are known to cross the bridge every day, along with around 150,000 pedestrians on the walkways.