Flowing in the Thames model

Published : Oct 21, 2005 00:00 IST

The Yamuna river resembles an open drain as it flows through Delhi. Here, the scene at Punjabi Ghat. - SHOVAN GANDHI

The Yamuna river resembles an open drain as it flows through Delhi. Here, the scene at Punjabi Ghat. - SHOVAN GANDHI

In yet another attempt to clean up the Yamuna river, the Union Ministry of Urban Development has adopted the Thames river model of constructing sewage treatment plants at points where the major drains empty into the river. If the plan fails it may be too late to save the river.

THE Union Ministry of Urban Development has unveiled a "Thames river" model to clean up the Yamuna and reverse the effects of the millions of litres of sewage that is poured into the river every day. An affidavit filed in the Supreme Court by Union Urban Development Secretary Anil Baijal states that sewage treatment plants (STPs) shall be constructed on the banks of the Yamuna at all the points where major drains empty into it. A timetable for the plan, spread over four years, has been drawn up and 14 companies have already responded to the tenders for the consultancy contract.

The Supreme Court consented to the plan on September 6 and recorded no major objections apart from expressing its anguish at the torpid pace of progress. The issue was brought before the court first in 1985 and since then it has seen a large degree of judicial involvement.

"The reason that the Yamuna is so dirty is that Delhi treats it like a drain and not a river," says Ravi Aggarwal, an environmentalist with Toxics Link, a non-governmental organisation (NGO) specialising in waste and pollution management. Indeed, all of Delhi's waste - domestic and industrial - is dumped into the river. Only some of the waste is treated. The Environment Pollution (Prevention and Control) Authority (EPCA), the National River Conservation Directorate (NRCD), and the Central Pollution Control Board (CPCB) have stated in their reports that the 22 kilometres of the Yamuna running through Delhi is its most polluted stretch.

The Yamuna enters Delhi at the Wazirabad Barrage, at which point water is drawn for Delhi's needs, and the river that flows through the city consists mainly of sewage discharged from 17 drains.

The Ministry of Urban Development now wants to ensure that, as a first step, the waste is treated before it enters the river. The project has been termed the "Thames proposal", as it is broadly based on the project implemented in the United Kingdom to clean up the Thames river.

Attempts to clean up the Yamuna have been many and the first serious one, by the Union government, was the Yamuna Action Plan (YAP-I) launched in April 1993. It was given the task of making the water fit for bathing by tackling the problem of domestic sewage; the problem of industrial effluents was to be dealt with under the existing environmental laws. The first phase of YAP ran until February 2003, after which the government launched YAP-II, scheduled to run until 2008.

YAP's main focus is the construction of infrastructure to deal with the massive amounts of sewage pumped into the Yamuna every day. The plan, which is being implemented in 21 towns across three States, involves the construction of STPs with a combined capacity of 900 million litres a day (MLD), repairing of existing sewerage systems, and the construction of low-cost toilets and crematoriums to deal with non-point pollution.

Delhi, specifically, has 17 STPs meant for domestic sewage, of which two have been funded by YAP, and 10 Common Effluent Treatment Plants (CETPs) for industrial waste. The treatment plants are meant to ensure that the water that enters the Yamuna has a Biochemical Oxygen Demand (BOD) of less than 20 milligram per litre and Total Suspended Solids (TSS) of less than 30 milligram per litre. Water, thus treated, should be fit for irrigation of sports fields, public parks and crops that are not eaten raw.

Given that the treatment plants are in place and that Delhi has spent around Rs.1,500 crores on Yamuna-related projects thus far, why is the Yamuna still so polluted? According to an internal memo of the Delhi Jal Board (DJB) made available to Frontline, a clean Yamuna is possible only when 90 per cent of the sewage entering it is treated. Senior DJB officials admit privately that most of the sewage treatment plants are working far below their capacity. The plants simply do not receive enough sewage, which is rather surprising in a city that produces approximately 2,800 MLD of waste.

The under-utilisation of STPs may be explained on two counts. First, 55 per cent of Delhi's population - the 45 per cent that stays in slums and unauthorised colonies and the 10 per cent that resides in jhuggi jhompri clusters - is not connected to the sewer system, according to the 2002-2003 Annual Report of the CPCB. However, this 55 per cent produces much less waste than the population in the colonies connected to the sewerage system because of very low per capita availability of water.

Second, domestic sewage does not reach the STPs because of faulty sewerage infrastructure. Unofficial estimates of leakage in Delhi's sewerage system range from 30 to 50 per cent. Since there is no way of measuring sewage lost, it is impossible to fix a definite value to the extent of leakage. In spite of YAP-I's emphasis on improving sewer pipes, the condition of Delhi's sewers remains abysmal. Alarmingly, most freshwater pipes and sewers are laid side by side, increasing the possibility of water contamination through leaks in the pipelines or corroded pipes.

Ironically, the DJB pumps treated water back into the drain from which it is drawn. In the absence of a parallel network, the STP, which is often miles away from the river, has a significant amount of treated water with nowhere else to pump it. Under the policy guidelines, the water has to be pumped to agricultural land for irrigation. However, Delhi's urban expansion has ensured that there is very little agricultural land left. Engineers at the DJB claim that pumping the water back into the drain increases the dilution factor in it and thereby reduces the pollution load on the river.

The condition of the CETPs - designed to treat industrial waste - is no different. An EPCA Special Report published in March 2004 states: "Most plants were complete in all respects but were not functioning. In some cases the waste was received by the plant and was discharged outside, without any treatment. In other cases the plant was simply bypassed and the waste was pumped directly into the drains." The report concludes: "Not only is there a complete and total waste of public funds, but also the purpose for which these plants were ordered has been negated."

The Delhi State Industrial Development Board (DSIDC), which operates the CETPs, says that work has been slowed down by issues relating to funding and ownership. Ideally, the CETPs should be part-financed by the industries that use them and managed by an industrial cooperative. However, the failure to arrive at a formula acceptable to all concerned has meant that assets built at the cost of Rs.256 crores are rusting away. While conceding that the EPCA report was factually consistent, Harjit Singh, Chief Electrical Engineer, Operations and Maintenance, DSIDC, said the ownership issues had been sorted out and 10 of the 15 plants were fully functional. However, problems with design and treatment persist.

The basic problem with the STP/CETP approach towards waste management is its excessive reliance on a centralised system of waste collection and treatment. High capacity plants are ineffective unless paired with extensive networks for sewage and treated discharge. The primary reason for the failure of most of the Yamuna proposals has been the emphasis on massive treatment units at the cost of adequate conveyance networks.

Sharad Gaur, an environmentalist with the Centre for Environment Education, an NGO associated with the public participation stage of YAP-I, said YAP's emphasis on the capacity augmentation could have worked against it. An emphasis on technological solutions to a fundamentally ecological problem meant that low-cost, decentralised options were ignored.

The first step towards reviving the Yamuna is ensuring that the volume of fresh water in the river is increased. An April 2000 report of the CPCB on the "Water quality status of Yamuna river" concludes that an estimated total flow of 18,000 MLD is required to maintain a desirable quality of water.

Apart from increasing the flow, the government should implement decentralised waste treatment on a pilot basis. This could take several forms, including community septic tanks and root-zone treatment. Apart from the low installation and running costs, decentralised systems ensure that water is treated close to the source and utilised locally, obviating the need for expensive water networks.

Instead of learning from the shortcomings of previous plans, the Thames plan seems to fall into the STP trap - building large and expensive plants that have to be serviced constantly with more and more sewage. The one major alteration is the insistence that the plants be built at the mouth of major drains, eliminating the problems of sewage supply and discharge and reducing transmission costs. However, this will render a significant number of STPs upstream redundant.

The DJB points out that the clean-up drive is still in the planning stages. If it succeeds, the Thames proposal shall accomplish in four years what could not be done in over a decade; if it fails, it may just be too late to save the river.

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