VALORIZATION OF GREYWATER USING MICROBIAL CONSORTIA FOR SUSTAINABLE REUSE IN URBAN AGRICULTURE

Abstract

Freshwater resources are becoming increasingly scarce, which is primarily caused by drought conditions, low rainfall, high evaporation, and high freshwater demands, as well as population growth, rising living standards, and economic factors. Greywater reuse and recycling is becoming more popular as a solution to the high urban water demand. Valorization of greywater refers to converting it from an inconvenience to a beneficial asset treating household wastewater and repurposing it for irrigation, flushing the toilet, or even industrial use. Greywater's composition reflects its many sources, with a combination of inorganic and organic materials, endocrine-disrupting chemicals, heavy metals, and microbiological pollutants. Concerns regarding possible health and environmental hazards related to untreated or inadequately treated greywater are raised by the presence of these chemicals. Treatment methods such as septic tanks, wetlands, aerobic and anaerobic systems, filtration, and disinfection have been applied, yet limitations persist. Biological treatment, especially through microbial consortia, offers a more sustainable approach by removing heavy metals and nutrients, reducing odor and colour, and enabling pollutant degradation. By offering an alternate irrigation source, greywater irrigation reduces reliance on freshwater reservoirs and promotes resource conservation. However, untreated greywater poses risks such as eutrophication, soil salinity, microbial contamination, and groundwater pollution. Future strategies should focus on optimized technologies, microbial consortia, and integrated treatment approaches to ensure safe and sustainable greywater valorization in urban agriculture.