Soil biotechnology at Nehru Park, New Delhi

Site visit done by: Amrita Bhatnagar
Date of visit: 7 August, 2017

Location: Opposite Ashoka Hotel, Chanakyapuri (28.594564, 77.195497)

Designed Capacity: 500 KLD (Design)
570 KLD (Actual)

Scale: Zonal

Operational since: April, 2017

Implementing Organisation: Vision Earthcare&EPC Ecosystem

Capital Cost: N/A

Area: 325 Sq. m

O&M: INR 3600/ year (cost of electricity) + INR 30,000/ month

Project Background
Located near the Diplomatic Enclave, New Delhi the Nehru Park covers an area of 80 acres. To supply water needed to meet the horticultural requirements of the park, was an uphill task. To deal with this problem, the New Delhi Municipal Corporation decided to build a decentralized sewage treatment plant which would treat sewage being pumped in from NDMC’s Santushti Complex.

Nehru Park‘s Soil Biotechnology STP is a part of NDMC’s (New Delhi Municipal Corporation) project of building 10 decentralized sewage treatment plants across the city on PPP (Public Private Partnership) model.

Treatment technology

The system comprises of the following components:

  • Inlet Chamber/Grit Chamber

The water enters the plant via this chamber .This is a small chamber meant to filter out any plastic waste.

  • Raw Water Tank

This tank is further divided into three parts

  • Filtration: The first part of the tank is fitted with a honey comb like screen with aperture size of 4 inch x 4inch.This is intended to filter out as much solid waste as possible.
  • Tube Settler: the second part of the tank has tube settlers installed which help in further treatment of water
  • Final Storage: This part of the tank involves collection of water from the previous two chambers.
  • Bio Reactor I

Water is pumped to the bio reactor with the help of a 3 HP pump, which then gets delivered to the plants with the help of sprinklers.60% of treatment gets completed, by the time the water flows out of the Bio reactor I. The bioreactor is made up of different layers of brick bats, aggregates and cultural catalyst.

  • Layer I: 10 mm Aggregates,

Thickness of layer : 150-200mm

  • Layer II :Cultural Catalyst(patented material)
  • Layer III :40-60 mm Brick media,

Thickness of layer:400mm

  • Layer IV:40 mm aggregate

Thickness of layer:100 mm

  • Collection Tank I

The water under the influence of gravity percolates through the bio reactor and gets collected in the collection tank 1.A 3 HP motor then delivers the water to the bio reactor II.

  • Bio Reactor II

The bio reactor II is identical to the bio reactor II and intends to facilitate another cycle of filtration. The water from the bio reactor II percolates into collection water tank II.

  • Collection Water Tank II

The water gets pumped to water hydrants with the help of a 10 HP motor.