Wastewater management in India

 

 

In news:

• Recent incident of severe water crisis in various parts of the country highlights the need for efficient waste water management practices in India.

 

Wastewater Generation in India

• India, one of the world’s most water-stressed countries, will become water-scarce with time. Per capita water availabile is set to decline to 1,465 cubic metres by 2025 from 1,544 m3 in 2011 (and 1,816 m3 in 2001), according to a 2018 Niti Aayog study.

• India generates a staggering 1.7 million tonnes of faecal waste a day. Official figures show that 78% of the sewage generated remains untreated and is disposed of in rivers, groundwater or lakes.
• The two main sources of water contamination are sewage and industrial waste. With both the population of India and its industrial landscape increasing at a phenomenal speed, wastewater volume is also at an alarming rise.
• Adding to this is the shrinking of freshwater sources like rivers, wells, and groundwater.
• Only one-third of India’s wastewater is currently treated, leading to the high burden of water-borne diseases.
• While urban water access is high on average, significant gaps remain across the country, and wastewater treatment remains stuck at the national average of around 33%.

 

 

Tapping wastewater

• Almost 80 per cent of the water supplied to a household is discharged as wastewater. The discharge is mostly untreated. So, it is a potential pollutant of ground water or being discharged into the natural drainage system, causing pollution in downstream areas and water bodies.
• As of now, only 30 per cent of India’s urban wastewater is recycled. The apathy with regard to sewage treatment plants (STPs) lies in the fact that those in urban spaces are neither properly financed nor designed.
• For example, in Delhi, the situation of wastewater treatment is better on paper. A consumption of 3,420 million litres per day (MLD) leads to wastewater of over 2,600 MLD. Of this 1,600 MLD is treated and 338 MLD is reused.

• Mumbai is worse. According to officials in the Municipal Corporation of Greater Mumbai, out of a supply of 3,750 MLD, 2,300-2,400 MLD goes into the sea, almost untreated.

 

 

 

Problems of waste water:

• Harmful effect on the river and marine life
• Lack of drinking water
• Overabundance of certain harmful chemicals in sources of water, some of which are chronic
• Adverse effect on groundwater
• Soil pollution
• Rise in chronic health conditions related to toxic chemicals like lead and mercury in all living creatures
• Rise of pollution in the coastal area
• Untreated wastewater poses a threat to both human health and our aquatic ecosystems, and is a challenge that is particularly acute in Asia-Pacific.
• The lack of attention and resources devoted to effective wastewater management ignores one of the most potentially effective means of addressing the global water crisis.
• Waste water is emerging as a thrust area for investment opportunities and is expected to grow in value and volume.

 

 

What are the various uses of waste water?

• Waste water is a resource in a circular economy.
• Waste water, once treated, can be recycled and/or reused for drinking purposes, in industry, in the artificial recharge of aquifers, in agriculture, in the rehabilitation of natural ecosystems and so on.
• Recycling waste water is not just an ecological imperative.
• By 2050, it is estimated, India will be water-scarce in terms of per capita availability of water per year.
• India’s demand for water is growing in all sectors, given continuing economic growth and improving lifestyles.
• Climate change, due to human induced interventions, will affect the variability of water supply in many countries, including India.
• This is difficult to achieve unless water is conserved, recycled and reused.
• It is also crucial to the growth of smart cities.

 

 

Dangers of waste water:

• Source: The sources of waste water are many: domestic, industrial, commercial, agricultural, surface run-off or storm water, and sewer inflow.
• Impact on human health: Untreated waste water is contaminated with urban waste containing not only a mix of chemical and biological pollutants, but also high levels of pathogens from excreta. This generally impacts human health.
• Impact on water bodies: Waste water is discharged directly into water bodies, overloaded rivers, lakes and the ground with toxic chemicals and wastes. This consequently poisons water resources and supplies.
• Ecological toxicity: These toxins feed their way into plants and animals, causing severe ecological toxicity at various levels, including in the human food chain.
• Biological magnification: This leads to biological magnification i.e the increasing concentration of a substance, such as a toxic chemical, in the tissues of organisms at successively higher levels in a food chain.

 

The Legal Mechanism for Waste-water Regulation in India

• The Water (Prevention and Control of Pollution) Act, 1974, amended 1988
  • This legislation was introduced to provide for the prevention and control of water pollution and the maintaining or restoring of wholesomeness of water.
  • It also provides for the establishment of boards for the control of water pollution.

• The Water (Prevention and Control of Pollution) Cess Act, 1977, amended 2003
  • This Act binds consumers who are carrying on an industry that falls within the provisions to affix meters for the purpose of assessing the quantity of water used in the act.
  • Industries also have to include operations or processes or treatment and disposal systems which consume water or give rise to sewage effluent.

 

 

Way ahead:

• More effective and efficient management of wastewater requires greater support of municipalities and local governments, which often lack the human and financial resources they need to enforce environmental rules and improve infrastructure and services. 
• A proper mechanism is needed to deal with wastewater. The existing centralised approach should not be considered the only method. This is due to the approach's limited sewerage network access, inadequate functional STPs and budgetary restrictions.
• Sound policy and regulatory interventions by the Central and state governments are a prerequisite for launching innovative reuse projects. Government interventions will need to focus on incentivising the use of reclaimed water and developing institutional support mechanisms.
• States including Gujarat, Maharashtra, Rajasthan, Chhattisgarh,  Karnataka and Madhya Pradesh have announced a wastewater treatment policy. 

 

Decentralised wastewater management approach:

Need and Significance:

• Cost effective: Decentralised wastewater management approach can be considered as a sustainable and cost-effective alternative as it treats, discharges or reuses the effluent in the relative vicinity of its source of generation.
• Low operation and maintenance: In the rapidly urbanising cities of developing countries, decentralised wastewater treatment systems are an attractive solution for addressing the problems of water pollution and scarcity. They have been promoted extensively due to their low operation and maintenance requirements and smaller scale investments.
• Feasible alternative: Decentralised wastewater treatment systems could be a feasible alternative for areas which are not connected to sewer networks as well as ones which are newly developed, so that the construction of their infrastructure is inadequate, not ready or would be executed in the future.
• Government schemes: Central urban development schemes — such as Jal Shakti Abhiyan, Swachh Bharat Mission, Atal Mission for Rejuvenation and Urban Transformation (AMRUT), Smart Cities Mission and Namami Gange — are crucial for wastewater treatment.
• They also emphasise the reuse of wastewater (including grey and blackwater) for various purposes, especially non-potable ones like horticulture and flushing.
• Instead of constructing large conventional STPs in which emphasis is placed on setting up a large infrastructure network, what we need to look at are alternative methods which don’t burden the economy and environment.
• Based on the size of the served area, there are different scales of decentralisation:

• Decentralisation at the level of a suburb or satellite township in an urban area — These systems are applied to small towns.
• Decentralisation at the level of a neighborhood — This category includes clusters of homes, gated communities, small districts and areas which are served by vacuum sewers.
• Decentralisation at ‘on-site’ level ( on site sanitation) — In these cases, the whole system lies within one property and serves one or several buildings.

• Decentralised and low‐cost wastewater treatment systems can augment limited treatment capacity. The mainstreaming of decentralised wastewater treatment systems needs a policy-level thrust from the government.
• Bioremediation: The National Green Tribunal recently said decentralised technologies such as bioremediation and / or phytoremediation or any other remediation measures could be started as an interim measures until STP units become functional.
• Not only government but also many institutes and non-profits like the Delhi-based Centre for Science and Environment (CSE), have for the past few decades, been advocating and capacitating practitioners on the approach of decentralised wastewater management, with the aim of recycling and reuse of wastewater.
• To generate awareness, involvement, and participation from local users for the decentralised approach, an online web-based tool —MOUNT (Menu on Un-Networked Technologies for Sewage and Septage Management) — is being created by the CSE which comprises successfully implemented decentralised wastewater treatment technologies.
• The socio-economic situation and the context of urbanisation highlight the need for decentralised wastewater solutions. In such circumstances, local reuse and recycling of treated wastewater too holds immense potential in terms of overall urban environmental sustainability.

 

Best practices:

International example:

The Singapore example

Singapore, for example, is using reclaimed water, branded “NEWater”, to serve up to 30% of its needs. While largely used for industrial purposes, the water is potable and demonstrates what can be accomplished through innovative policy approaches. The largely industrial use of NEWater also points to wastewater’s potential benefits for food production and industrial development.

 

 

Domestic example:

Best Practices in Wastewater Management

• Avadi Sewage Treatment Plant: Sustainable off-grid sewage treatment in Chennai
  • The Tamil Nadu Police Housing Corporation (TNPHC) has successfully constructed an off-grid sewage treatment plant (STP) to improve living conditions in the police housing colony in Avadi, a suburb of Chennai.
  • This sewage treatment plant has not only solved the problem of sewage disposal but also provided a pond of treated water for fishing, vegetable cultivation and recharging of groundwater.
  • It treats 12 lakh litres of sewage every day with no negative discharge, produces manure, recharges groundwater, removes the source of foul odour and waterborne diseases, and beautifies the area.
• Sewage-fed aquaculture system of Kolkata: A century-old innovation of farmers

• Farmers around Kolkata city in India developed a technique of using domestic sewage for fish culture and other agricultural purposes, almost a century ago. This technique is widely used to meet the growing demand for fish. The technique is considered to be unique and is the largest operational system in the world to convert waste into consumable products.

 

 

Conclusion:

With the country hurtling towards a water crisis and treated wastewater a possible alternative, using models that are different from the centralised approach, is a sustainable and cost-effective solution. If appropriate and time-bound measures are not taken, the country may have to confront a series of associated problems, ranging from health issues due to poor sanitation and conflicts over water access, to food security and climate change.

 

 

Source)

https://timesofindia.indiatimes.com/city/delhi/dutch-treat-barapullah-drain-project-enters-ph-ii/articleshow/71588384.cms