Convenient solutions to inconvenient truth: Domestic wastewater management-based approaches to sustainable development goal no. 6

Most cities of low- and middle-income countries in Asia, in which more than 80% of the urban population is facing wastewater collection and treatment problems, generally employ conventional centralized systems to treat wastewater from bathrooms and kitchens. Despite the Sustainable Development Goal No. 6 (SDG6) targets which aim to improve unsafely managed sanitation conditions by 2030, about 2.8 billion people are still employing unsafe sanitation facilities which usually cause environmental impacts and faecal pathogen infections. Because of this problem, the challenge in identifying convenient solutions on safe domestic wastewater management is needed to accomplish the SDG6 targets. This research evaluates the existing domestic wastewater management of some cities in Southeast Asian countries (Indonesia, Thailand, and Vietnam), and proposes some convenient solutions based on four important indicators. These indicators included collection and treatment performance for domestic wastewater management, cost-benefit ratio, and social content. Based on actual domestic management data compiled from the 55 cities in three Southeast Asian countries, influencing factors affecting effectiveness of domestic wastewater management of these cities were classified using Response Surface Methodology (RSM) techniques. Domestic wastewater management effectiveness chart was generated and tested with the five tested cities in three Southeast Asian countries having similar domestic wastewater management conditions during the period January–June 2021. The convenient solutions on safely domestic wastewater management were proposed such as contributing the capacity of wastewater collection to be 20,000 m³ per day per 5,000 households, and introducing the wastewater collection fees covering the full cost of operations and maintenance to accomplish the SDG6 targets on safe domestic wastewater management.