Sewage

It is really very strange that Delhi, which is India’s national Capital, one of the fastest growing metropolitan cities of the country, does not have a proper sewage disposal and drainage system. Delhi is facing severe problem of untreated sewage such that only about 55% homes in Delhi are linked to a proper sewerage and the rest of the 45% of wastes goes in to the Yamuna river directly.

In fact, it is really very sad to say that the faeces of the functional commodes of the modern bathrooms in urban Delhi are contributing to the pollution of Yamuna. In spite of the fact that a number of plans and programmes have been implemented by the Government for sewage and wastewater treatment, these are not being able to keep pace with the growing generation of waste water. While there are certain sections like developed and organized areas of Delhi which are given wastewater treatment services to a certain extent, the slums or the unorganized areas are not provided any sewage treatment, the reason being they are not within the jurisdiction of the Delhi Jal Board (DJB).

Facts and figures of sewage treatment in Delhi

According to report published in 2012, only about 30% of all the sewage that comes in Delhi is treated. It has been estimated that on an average per day 3296 million litres of sewage is dumped in the Yamuna. Per day, Delhi generates around 600 million gallons of sewage, but the sewage treatment plants (STPs) set up in Delhi have a capacity to treat only 512.4 million gallons of waste.

On November 11, 2012, the Supreme Court had declared that all parameters of water quality of Yamuna more or less are similar to a drain. Also, the national Capital does not have a proper drainage system and sewer lines. There are 30 sewage treatment plants located at 17 locations in Delhi, out of which only two are running within the capacity limit, 20 are running under capacity, five are running over capacity and three are non-functional.

Outcome of sewage problems

Improper and inadequate sewage treatment have impacted the environment and the citizens of Delhi in many ways:

  • Malfunctioning septic systems have resulted in contamination of well water, ground water, river water and causing threats to public health
  • Untreated and open drainages have produced conducive breeding for mosquitoes, flies, rodents, insects and other diseases carrying vectors.
  • Untreated sewage have led to stinking and foul smell
  • Direct physical exposure to wastewater for people bathing and washing clothes and utensils
  • Toxic food farming has increased around the Yamuna river due to improper sewage treatment, leading to various diseases like as vomiting, gastroenteritis, diarrhea, blood infection, dehydration, kidney dysfunction and urinary infection.
  • The toxins have polluted the ground water and soil.

Who is responsible for the wastewater and sewage treatment in Delhi?

The Delhi Jal Board (DJB) is the authority responsible for planning, execution, designing of water supply and wastewater and sewage management within its jurisdiction in the National Capital Territory of Delhi. As per DJB, the sewerage system available in various categories are as follows:

  • Planned colonies (only 40%)
  • Unauthorized regularized colonies
  • Resettlement colonies
  • Urban villages
  • Rural villages, unauthorised colonies and JJ Cluster

Major problems in sewage treatment

  • Delhi’s population is growing everyday and this is one prime reason that affects the sewerage services available to its citizens.
  • Most of treatment plants do not perform effectively due to operational problems.
  • The present capacity of the STPs is underutilized on account of deficiency in the collection system.
  • The large network of sewers and drains in the city is very old and most of them are small and also in damaged condition.
  • Low flow of sewage to STPs
  • No proper sewage management and planning
  • Delhi Jal Board had not prepared any “proper and perspective” plan for sewage treatment.
  • High cost treatment but low cost recovery that forces DJB to depend on excessive loan help from the Government.

Other problems

  • Lack of infrastructure
  • Weak financial base
  • Corruption
  • No co-ordinating body
  • Lack of political will
  • Lack of accountability etc.

What is the solution? Opt for decentralized small-scale sewage treatment systems

As per a report by the Delhi Government of 2013, between 2007 and 2012, Rs 3,132.50 crore have been spent in sewage treatment programmes in the Capital city. In Delhi today, there is a deficit of 9,500 km sewage pipeline and an investment of Rs 25,000 crore is required to build these sewage pipelines. The DJB has spent around 1,634.18 crore in 2011-12 on the operations, maintenance and construction of STPs but of no relevant outcome.

The Government and the DJB should consider decentralising its sewage treatment system. Decentralized sewage treatment also known as “Onsite wastewater treatment system” is one that treats discharges, sewages, wastewater at the location itself where the sewage is generated. For example, we still have the simple system of septic tanks and leach fields serving single homes in various towns and villages in India. Instead of sending the wastes into a huge STP in a particular location, the water is treated and returned to the ground on the same area.

A centralized STP collects sewage from various locations of the city and then treat it. But this system requires large amounts of capital investment and is highly labour intensive which require regular maintenance and make use of large amounts of electricity and in most cases is non-functional.

That is why, opting of privatisation or decentralisation of sewage water treatment is a good solution. The resident welfare associations should be made responsible for operation and maintenance of the decentralised sewage treatment. In fact, many real estate developers in Delhi have already implemented this in the various townships and apartment societies located in Delhi. Decentralized small-scale sewage treatment systems are an efficient way of planning and upgrading Delhi’s urban environment to a sustainable level.