On any given day, a dip in the toxic and foamy waters of the Yamuna river in Delhi remains unthinkable. However, on Nov. 17, over 150,000 people visited the river banks to celebrate the Chhath festival and brave the river's pollution in the name of faith.

Celebrated eight days after Diwali, the Chhath festival is centred on the worship the sun and water gods. In Delhi, it is observed by people from the eastern part of India, especially the states of Bihar and Uttar Pradesh. The devotees fast and offer water and milk to the sun god and the Chhathi Maiya goddess at dawn and dusk.

The Yamuna river has been affected by pollution for decades despite several government drives to clean up its water and the investment of millions of dollars to preserve its ecosystem. The river has been declared "dead", with its water not suitable for bathing at most places, leave along supporting aquatic life. The pollution comes from the discharge of industrial pollutants, as well as untreated waste from cities.

Afterwards, numerous devotees complained about the stinking and contaminated water, and many of those who took the dip were afflicted with skin rashes, allergies and even breathing problems. Meanwhile, the celebrations left the river banks littered with leftover offerings.

Hindu devotees offer prayers to setting sun during the Chhath festival on the banks of river Yamuna, on Nov. 17 in Delhi. Image: Burhaan Kinu/Hindustan Times

A Hindu devotee stands amidst the foam in the Yamuna river to offer prayers during the Chhath festival on Nov. 17. Image: Burhaan Kinu/Hindustan Times

Devotees gather to offer prayers to the setting sun during the Chhath festival on the banks of river Yamuna, on Nov. 17. Image: Burhaan Kinu/Hindustan Times

Religious offerings from devotees and leftover wooden frames, earthen lamps and other pile up on the banks of Yamuna river after the end of Chhath Puja festival, on Nov. 18. Image: Burhaan Kinu/Hindustan Times