Treating and Reusing Wastewater

Why most of India's urban sewage goes untreated, how treated wastewater can be reused, and the economics of treatment plants.

Indian cities produce huge amounts of sewage, but much of it goes untreated.

The gap

According to Central Pollution Control Board estimates, India’s sewage treatment capacity has covered only a portion of urban sewage generation, and many plants operate below capacity.

Consequences

Rivers like the Yamuna in Delhi become heavily polluted.
Health risks from contaminated water.
Groundwater contamination.

Reuse

Treated wastewater can be used for:

Industry: cooling in power plants and factories.
Agriculture.
Gardening and flushing.
Groundwater recharge.

Examples

Nagpur sells treated wastewater to a power plant, earning revenue.
Chennai supplies treated water to industries.
National rules require thermal power plants near cities to use treated sewage water.

Economics

Treatment plants cost money to build and run; many fail due to poor maintenance.
Selling treated water creates revenue to pay for operations.

Namami Gange

The Namami Gange programme (2014) built sewage treatment plants along the Ganga.

The power plant's water

Nagpur's municipal corporation sells treated sewage to a nearby power plant, earning money while saving fresh water for residents.

Thinking sewage is only a waste problem

Treated wastewater is a valuable resource for industry and farms.

Key takeaways

Much urban sewage in India goes untreated.
Untreated sewage pollutes rivers and groundwater.
Treated wastewater can be reused by industry and farms.
Selling treated water can fund operations.