A toxic foam from Bellandur Lake has spilled onto the streets of Bengaluru, causing health problems and bringing an unbearable stench to the city.

Bellandur is one of the largest lakes in the city, and for the last decade, the foam has become an annual issue for the city’s residents.

Many of the lakes in the city experience a similar problem, due to the amount of pollution in the waterways. This pollution consists of sewage, industrial waste and household debris.

The problems occur in summer after a downpour. The rain mixes with the high content of ammonia and phosphate in the local lakes and generates a vast amount of froth.

After the piles of foam build, even a light wind can then pick it up and send it flying across roads and into nearby buildings.

At the Indian Institute of Science, Professor TV Ramachandra, who has been studying the Varthur Lake since 1997, confirmed that the pollution has been getting worse year by year.

He told NDTV that the nitrates that are found in the lake are carcinogenic, and the phosphates are causing the froth.

Locals say that the foam irritates the skin and is a breeding ground for diseases. They also claim that they cannot park their cars near the lake, as the toxic foam fades the colour of the paintwork.

In May last year, the lake even caught fire. It’s believed that the fires were caused by industrial waste in the water including detergents, oil and grease.

The pollution is a great shame for the city which was once known as the city of a thousand lakes.

However, the city famed for its interconnected lake systems has seen many of these lakes dry up or used as rubbish dumps. Now there are only about 150 lakes still in existence and almost all of these are severely polluted.

Instead of dealing with the pollution, authorities installed a fence attempting to prevent the foam from escaping onto the roads.

However, when part of this fence collapsed a few days ago, the froth escaped across the roads once more.

Additional reporting by Steff Gaulter.

Source: Al Jazeera and agencies