From UPSC perspective, the following things are important :
Prelims level : Important facts mentioned
Mains level : Wastewater treatment in India
Sewage treatment plants (STPs) in India are able to treat a little more than a third of the sewage generated per day, according to the latest report of the Central Pollution Control Board (CPCB).
What is Wastewater?
Wastewater is used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/ stormwater, and any sewer inflow or sewer infiltration.
In everyday usage, wastewater is commonly a synonym for:
- Sewage also called domestic wastewater or municipal wastewater which is wastewater that is produced by a community of people.
- Industrial wastewater, water-borne waste generated from a variety of industrial processes, such as manufacturing operations, mineral extraction, power generation, or water and wastewater treatment.
- Cooling water, released with potential thermal pollution after use to condense steam or reduce machinery temperatures by conduction or evaporation
- Leachate, precipitation containing pollutants dissolved while percolating through ores, raw materials, products, or solid waste
- Return flow, carrying suspended soil, pesticide residues, or dissolved minerals and nutrients from irrigated cropland
- Surface runoff, the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil.
- Urban runoff, including water used for outdoor cleaning activity and landscape irrigation in densely populated areas created by urbanization
- Agricultural wastewater, generated from confined animal operations
Wastewater in India
- India generated 72,368 MLD (million litres per day) whereas the installed capacity of STPs was 31,841 MLD (43.9 per cent), according to the report.
Treatment facilities available
- Of this installed capacity, developed and operationalized capacity was 26,869 MLD (84 per cent).
- Of the total operationalised capacity, 20,235 MLD (75 per cent) was the actual utilised capacity.
- In other words, out of total 72,368 MLD sewage generated every day, only 20,235 MLD is treated.
- Five states and Union Territories (UT) — Maharashtra, Gujarat, Uttar Pradesh, Delhi and Karnataka — account for 60 per cent of the total installed treatment capacity of the country.
- These, along with five other states and UTs — Madhya Pradesh, Haryana, Punjab, Tamil Nadu and Rajasthan — alone constitute 86 per cent of the total installed capacity.
- Arunachal Pradesh, Andaman & Nicobar Islands, Lakshadweep, Manipur, Meghalaya and Nagaland have not installed sewage treatment plants.
- There are states like Bihar which do have a small installed capacity of STPs. But on the operational front, they score a zero.
- Chandigarh ranks first in terms of total sewage generated to what is actually treated. It generates 188 MLD of sewage and has an operational capacity to treat 271 MLD.
Major issue: Reuse of sewage
- The reuse of treated sewage is an issue which hasn’t assumed much importance in the policy planning of many state governments.
- Treated sewage water can be reused for horticulture, irrigation, washing activities (road, vehicles and trains), fire-fighting, industrial cooling, toilet flushing and gardening.
- The proportion of the reuse of treated sewage is maximum in Haryana (80 per cent) followed by Puducherry (55 per cent), Delhi (50 per cent), Chandigarh (35 per cent), Tamil Nadu (25 per cent), Madhya Pradesh (20 per cent) and Andhra Pradesh (5 per cent).