Shortly after the conclusion of the dreaded final examinations, my parents planned an impromptu and much needed trip, to Agra. Three suitcases, a heavy breakfast and a change of clothes later we were ready for the 3 hour road trip. Naturally, my attention was occupied by the road full of cars and the same prosaic sights that have caught my attention year after year. The infrastructure and road development made it visibly transparent to the traveller that they are slowly moving further away from the metropolitan city of Delhi. We passed by the garbage dumping grounds, masking all of the city’s waste, everything hidden and kept far away from the central areas of Delhi. Heaps of garbage forming walls, foul to our delicate sense of smell and sight, and attracting rats and crows- an accumulation of the unwanted and insalubrious. A short distance later, we came closer to river Yamuna, one of the major rivers in northern India which passes Delhi, where it feeds the Agra Canal. I took a cursory glance at the view outside the car and noticed something resembling snow on the sacred Yamuna. On taking a second glance, the white substance appeared to be foam. This reminded me of detergent or the foam formed when taking a bath. In addition to the foam, a foul sewage like smell and garbage along the banks of the river, corresponding to the dumping grounds.

What is this harmless looking yet toxic substance inhabiting one of India’s holiest rivers?

Yamuna, the second largest tributary river of the Ganga and the longest tributary in India accounts for 57 million people who depend on the Yamuna along its course and accounts for more than 70 percent of New Delhi’s water supply. Taking a dip in river Ganga is a ritual infused with religious beliefs. The Yamuna is highly venerated in Hinduism, according to popular legends, bathing in or drinking its waters is believed to remove sin. It is also considered as a blessing.

Today, the holy waters are covered with toxic foam substance caused by industrial and human waste.
Attributed to the high phosphate content of the water, the thick foam is caused because of detergents used in dyeing industries, dhobi ghats and households. These detergents and other organic matter gets deposited in the riverbed when the river is flowing normally. When more water is released upstream, it falls from a height on reaching the Okhla Barrage, leading to turbulence and churning which causes froth.
Another (minor) reason for the frothing is the release of certain gases when a specific kind of bacteria become active in anaerobic conditions ie, when there is no or little oxygen is available.
Sewage from Delhi and other cities, chemical waste from manufacturing plants and pesticide runoff are all part of the problem. The river is considered one of the most polluted rivers and ecologically dead. Yamuna is joined only by the Somb, a seasonal rivulet from Haryana, and by the highly polluted Hindon River near Noida, so that it continues only as a trickling sewage-bearing drain before joining the Chambal at Pachnada in the Etawah region of Uttar Pradesh.
The discharge of wastewater through 15 drains between Wazirabad barrage and Okhla barrage renders the river severely polluted.

There are three main sources of pollution in the river: household and municipal disposal sites, soil erosion resulting from deforestation occurring to make way for agriculture, and resulting chemical wash-off from fertilizers, herbicides, and pesticides and run-off from commercial activity and industrial sites. The water also contains faecal coliform. It may cause health hazards. Some waterborne pathogenic diseases that may coincide with fecal coliform contamination include ear infections, dysentery, typhoid fever, viral and bacterial gastroenteritis, and hepatitis A. Another reason for an increase in the pollution of the river is poor connectivity between drains and sewage treatment plants. This has caused the discharge of untreated sewage at different locations of the river Yamuna and thereby breeding of unwanted bacteria
River Yamuna poses as a threat to not only people who live nearby but also all water dependent living organisms.

There have been a few river restoration projects focused on improving the state of Yamuna, most famous being the Yamuna Action Plan (YAP).

The Yamuna Action Plan (YAP) is a bilateral project between the Government of India and Japan, introduced in 1993. It is one of the largest river restoration projects in India. Phase I, which began in 1993, marked its end in 2003, even though it was expected to be completed by 2000. The Yamuna Action Plan Project Phase II, was set in motion in 2003, and is regarded as the core project under the National River Conservation Plan of Government of India. The project tackles the abatement of serious pollution of the River Yamuna by raising sewage treatment capacity, caused by rapid population growth, industrialization and urbanization in the towns of the river basin, which includes Delhi, the capital of India. Building new and expanding capacity of old sewage treatment plants and laying and rehabilitating sewers will be done to enhance the treatment capacity particularly in Delhi and Agra. These works will lead to improvement and upgradation of the sanitation conditions for the inhabitants of towns in the river basin. The failures of the Yamuna Action Plan (YAP) are apparent in terms of the water quality, river Yamuna has not shown the desired improvement owing to a large gap between the demand and availability of sewage treatment capacity and lack of clean potable water in the river.
The YAP Phase III project for Delhi has been approved by the Environment ministry at an estimated cost of ₹ 1,656 crore with loan assistance from Japan International Cooperation Agency. According to Jayanti Natarjan (Environment Mininster) ,two projects have also been sanctioned by the ministry at an estimated cost of Rs 217.87 crore for taking up works related to pollution abatement of river Yamuna in Sonepat and Panipat in Haryana located upstream of Delhi. The plan is yet to prove its effectiveness and provide results.