A lecture on Solid Waste Management was organised at the Conference Hall of the Department of EVS, Nagaland University, Lumami, in hybrid mode on 21st October 2026, by the University’s Committee for Mission LiFE. The resource person, Prof. Ligy Philip, Institute Chair Professor, Dept of Civil Engineering, IIT Madras was introduced by Peter Ki, PRO, Nagaland University.
Prof. Philip shared that effective solid waste management has emerged as a critical requirement for protecting public health, preserving soil and water resources, and promoting sustainable development. She highlighted that waste generation varies considerably between rural and urban areas, with rural communities generating approximately 0.1 to 0.4 kg of waste per capita per day, while urban areas generate between 0.5 and 1.2 kg per capita per day. The higher generation rate in towns and cities is largely attributable to packaged and ready-to-eat food, commercial activity, rising incomes, and changing lifestyles. In rural areas, although a major share of domestic waste is biodegradable, much of it is reused within households for feeding livestock and therefore does not always reach central waste-management facilities.
Improper disposal of solid waste, particularly through open dumping, poses serious environmental and public-health risks. Rainwater percolating through unsegregated waste produces leachate, which can carry heavy metals, organic pollutants, and hazardous household fluids into groundwater and surface-water sources. Plastic waste further degrades soil structure, reduces water absorption capacity, and affects agricultural productivity. Open dumping also encourages the breeding of disease vectors such as rats and mosquitoes, releases methane from decomposing organic matter, and contributes to air pollution. The growing presence of microplastics - plastic particles smaller than five millimetres - has added a new dimension to the problem, as these particles can adsorb toxic pollutants and potentially contaminate soil and groundwater.
Prof. Philip emphasized that a sustainable waste-management system must begin with proper classification and segregation at the source. Waste should be separated at minimum into organic or biodegradable waste, non-biodegradable waste, and sanitary waste. Organic waste, including kitchen and garden waste, can be converted into compost or used for biomethanation. Non-biodegradable waste includes plastics, paper, textiles, metals, glass, electronic waste, and similar materials, many of which can be recycled if kept clean and segregated. Sanitary waste, such as diapers, sanitary napkins, bandages, syringes, and needles, requires separate handling to prevent contamination of recyclable materials and to protect sanitation workers.
The preferred hierarchy of solid waste management places source reduction and reuse at the top, followed by recycling, composting, waste-to-energy recovery, and finally sanitary landfilling. Source reduction and reuse - such as carrying cloth bags instead of accepting single-use bags - remain the most sustainable option because they prevent waste from being generated in the first place. Recycling recovers valuable materials such as paper, plastic, metal, and glass, while composting converts biodegradable waste into nutrient-rich soil conditioner. Landfilling should be treated only as the last option for residual waste after maximum resource recovery, and it must be distinguished clearly from open dumping. A sanitary landfill is an engineered facility with protective liners, leachate-collection systems, daily covering, and measures to prevent groundwater contamination.
Prof. Philip went to point out that composting was identified as one of the most practical and decentralised solutions for managing biodegradable waste. In proper aerobic composting, organic waste should reach a temperature of approximately 55 to 60 degrees Celsius for three to five days, a condition that helps destroy pathogens. Mature compost is generally produced within 20 to 60 days, depending on the method adopted. Maintaining an appropriate carbon-to-nitrogen ratio of about 30:1 and moisture content of around 40 to 45 per cent is essential for effective decomposition and odour control. Methods such as pit composting, windrow composting, vermicomposting, and mechanical or in-vessel composting can be adopted according to the scale of operation, from individual households to municipalities.
Community participation and local-level implementation are essential for the success of any waste-management initiative. The discussion referred to a corporate-social-responsibility-supported sustainable-villages programme implemented in more than 12 villages, integrating segregation, collection, composting, recycling, wastewater management, and community training. In one village, improved composting practices reportedly produced mature compost within 20 to 25 days, which was sold at ₹25 per kilogram. Income from compost and recyclable materials was stated to meet approximately one-third of the operating costs. The initiative demonstrates that with awareness, community involvement, appropriate infrastructure, and sustained local participation, solid waste can be transformed from an environmental burden into a valuable resource, asserted Prof. Philip.
The lecture also included a Q&A session. The vote of thanks was proposed by Dr. Latonglila Jamir, HoD, Dept of EVS, Nagaland University. The lecture was attended by faculty, staff, research scholars, PG students, and members of the University’s Committee for Mission LiFE.
