100 KLD Reedbed Based Pilot Project for Sanitation Improvement Plan at Ayanagar, New Delhi

Ayanagar was a clear example of the lack of a proper drainage system. The surface run-off usually mixes with the sewage water in open drains and overflows, making the streets completely unhygienic. Looking at these drastic conditions, in 2008 the Government of Delhi under a scheme of the Delhi Kalyan Samiti granted research aid to GREHA, an NGO primarily consisting of environmental design and planning experts based in Ayanagar, to propose options and possibilities that can be initiated to make Ayanagar a real model. To design an effective drainage system in these conditions, it was evident that the centralized municipal system, which originated in Europe in the nineteenth and early twentieth century, was not appropriate. Hence, GREHA proposed a new technology called small scale sewer system which could be installed below the roads without entering the private houses.  The treated effluent from the bio digesters would undergo secondary treatment through bio-remediation in a Constructed Wetland or Reedbed System in the nearest suitable open space available.

The Reedbed system is put up in Z-block, Ayanagar which caters the population around 590. Prior to this initiative, there were two types of systems available for sewage retention and disposal. In-house septic tanks with random sizes. The grey water and storm water flowed along the street in the storm water gutters which further discharged into the nearby water body.

• Some of the households had constructed local sewer lines from which the sewage got directed into the road side open drains which ultimately ended up in the local water body.

Following are the different steps involved in the treatment process:

Step 1: Pre-treatment unit in each households which included immobilization matrix enclosed in a permeable membrane. The immobilization matrix is loaded with Defence Research and Development Organization (DRDO) developed Anaerobic Microbial Inoculum (AMI). The permeable membrane retains the colonized bacteria of AMI inside whereas it also allows diffusion of AMI into the cess pool.

Step 2: Existing on-site sanitation system is being used for interception of the black water. An outlet is provided for all the on-site systems and the effluent from the systems is diverted to an intercepting chamber.

Step 3: Black water from the intercepting chamber flows into an adjoining biodigester.

Step 4:  The rainwater has been intercepted and conveyed to stormwater drains to eventually reach the greywater intercepting chamber. Parallely grey water from the household biodigester also reaches the intercepting grey water chamber.

Step 5: The mixed wastewater (effluent from biodigester, grey water from the households and collected rain water) goes into the collection tank from where it is pumped out into the reedbed.  

Step 6: After natural treatment in the reedbed it is further collected into a collection tank.

Step 7: Reedbed treated effluent is passed through multi grade filter and activated carbon filter for final treatment and disinfection. This treated water is stored into a treated water storage tank and being reused for the various purposes. The surcharge water is being discharges into the nearby Johad.

Mr. Manoj Jha
Director
Arkin Creations Pvt Ltd
Mobile No: +91 8826419993
Email Id: manoj.jha@arkin.org.in
arkincreations@gmail.com

Mr. MN Ashish Ganju
Architect
Mobile No: +91 981988114
Email Id: mnashish@gmail.com