An experiment of decentralized solid, liquid and energy management in a Delhi colony is unique because the efficient functioning of a well planned waste and energy management system. The experiment demonstrates that clean environment is not a burden on the exchequer and the ecosystem benefits from reduced burden on the water table, energy and resources
Waste is a by-product of living. Expenditure towards commuting, housing and living in urban areas is accepted as the investment required for attaining a high standard of life. However, the ever-increasing costs of natural resources due to the fast pace of urban growth is being ignored, whose deterioration is contributing to increased expenditure in healthcare too.
Issues of Municipal Solid Waste:
In our haste to get rid of our waste, we have created garbage-mountains of 35 metres in height (e.g. Ghazipur dumpsite) extending to at least 100 acres, which is about 0.014 km3. We have also contaminated our ground and sub-soil water through dumping besides putting out toxic emissions and dust into the atmosphere from burning in incinerators.
A viable alternative:
Case Study - Solid Waste, Waste water, Energy Management at New Motibagh, New Delhi
The General Pool Residential Accommodation (GPRA) complex at New Motibagh is a 110-acre campus housing about 1000 families of bureaucrats and their domestic help. This residential complex located in South Central Delhi, stands out among other upscale colonies in Lutyens Delhi, which are major water and energy guzzlers. The GPRA complex, constructed and maintained by National Building Construction Corporation (NBCC) Ltd, was developed for the Ministry of Urban Development, Govt. of India between 2008 and 2012. The NBCC put in place decentralized waste water and municipal solid waste management system for the houses at New Motibagh and integrated a solar energy street lighting and solar water heating system with the housing plan.
An Integrated System: This experiment of decentralized solid, liquid and energy management at the GPRA complex, New Motibagh is unique because the efficient functioning of a well planned waste and energy management system, demonstrates that clean environment is not a burden on the exchequer and the ecosystem benefits from reduced burden on the water table, energy and resources.
Waste Water Management: About 70% of the 8 lakh litres of water supplied to the residents, that is, 5.6 lakh litres of waste water generated is treated in a decentralized waste water treatment plant within the campus using the Moving Bed Bio-reactor (MBBR) technology. There is a net savings of Rs.5 lakhs per annum due to direct and indirect savings from a decentralized Waste Water Treatment plant (WWTP) in the campus whose running cost is Rs.55.55 lakhs as opposed to the centralized sewerage system costing Rs.60.62 lakhs.
Savings from Decentralized waste and energy management system:
||Amount in Lakhs of
Rupees per annum
||Surcharge of 50% on water bill for non-disposal of sewage to municipal system
||Using Treated Water from STP for gardening in the campus
||Using Sludge cake from STP
||Laying long trunk for irrigation and sewerage and pumping
||50,000 litres per day of treated waste water given free to NDMC
Solid Waste Management: Similarly, the Solid Waste Management project run by M/s Green Planet Waste Management (P) Ltd. (Operator) in collaboration with NBCC, who spent Rs.20 lakhs for providing 4000 Sqft of covered sheds and the Operator who has invested Rs 50 Lakhs on machinery, garbage bins at common places, collection trolleys/ cycle rickshaws , is now self-sustainable.
The process: The total generation of waste from the households and shops is 1.5 MT while the garden waste accounts for another 1 MT. Of the household waste, the wet compostable waste from households is about 1 MT per day which is converted to compost using the Excel method, using a composter, which does size reduction as well as mixing of wet waste with the inoculum. This is followed by composting in trays kept on racks, humidified and turned daily for about 2-3 weeks yielding about one fourth of its weight as compost, which is cured, sieved and packaged to be sold at Rs.5 per kg. Similarly, a pelletization assembly for cutting, drying, compressing and pelletizing garden waste generates about half its weight in pellets to be sold at Rs.8-9 per kg. The running cost for all activities is Rs.3,02,800 per month.
It is estimated that about 25 – 30 MT of compost and pellets are generated per month yielding about Rs.2 to 2.5 lakhs. Sale of recyclables especially paper helps to attain break-even. In addition, a plastics to fuel oil equipment has also been installed whose economics and contribution to the revenue is yet to be calculated. The big drawback is that residents do not segregate wet from dry waste, which has to be done by waste workers at the segregation area and the company is not insisting that the residents do it.
The energy savings from 300 solar street lights at the GPRA complex, covering internal roads, common areas, parking lots and bunglows, help in saving Rs.32.28 lakhs per annum. Along with solar water heaters, the savings on electricity is close to Rs.35 lakhs a year.
Therefore, a decentralised integrated solid waste, waste water and energy project for about 1000 households can achieve clean and green surroundings and financial savings to the tune of Rs.40-50 lakhs per annum. Green surroundings, ground water recharge and the reduction in carbon footprint achieved are yet to be monetized.
Land requirement for Decentralized Waste Management: The land requirement is around 6000 – 7000 sq ft for 1000 households (HH). In a well-planned locality this would be about 10 ft3 (taking average population to be 6 per HH) or 0.28 m3 per person almost permanently. In the case of mere dumping of waste in a landfill, the per household land requirement per year is 0.0003 cm3 or .0075 m3 which will be exhausted in 25 years or less if the average household garbage generation is 0.5kg/day as estimated in India. Hence, a landfill of 100 acres with the allowable height of 20 metres will barely last for 20 years. Therefore, allocating 0.28 m3 per person permanently for waste management in the city is worth it.
Planning for Integrated Waste Management in the city:
As per its master plan, Delhi has allocated 200 sq m for Dalaos in common areas for every 10,000 population, which is about 0.2m3 per person, which is what we require, especially for decentralized Solid Waste Management (SWM). If the space is appropriately modified and used, then the solid waste issue can be solved.
In addition if space along the large drains or Nallas is used for innovative technologies for decentralized treatment of waste water, then decentralized Solid and Liquid Waste management can be achieved within the city. In a city like Delhi, with a population of 12 million, a total of 0.003 km3 would be required in small pockets, which is less than 25% of the land being wasted by one of our landfills.
Therefore, we need to focus on segregation and recycling. Maintenance and efficient running rather than creation of huge assets will help us achieve this. Let’s take this first step and make our cities cleaner, greener and healthier.