The History of Toilets and Sanitation: From Ancient Rome to Today

The means of implementation (MOI) for SDG6 encompass financial resources, technology transfer, capacity building, trade, regional integration, and national enabling environments. Targets 6A and 6B address international cooperation and community participation respectively. However, current monitoring faces challenges including institutional gaps, limited scope beyond WASH, and inadequate data linkage between finance and outcomes. The strategic assessment identifies these issues to guide improvements leading to 2030 and beyond.

SDG 6 (Clean Water and Sanitation) is one of the 17 UN Sustainable Development Goals dedicated to ensuring the availability and sustainable management of water and sanitation for all by 2030, encompassing targets for safe drinking water access (2 billion people still lack it), adequate sanitation and hygiene (3.6 billion lack safely managed sanitation), improved ambient water quality, addressing water scarcity affecting 2.3 billion people, integrated water resource management, and protecting water ecosystems, with implementation requiring international cooperation and local community participation.

WHO and UNICEF's 2025 report reveals that low-income countries face open defecation rates four times higher than the global average. While 1.2 billion people gained safe sanitation access between 2024-2025, global coverage only rose from 48% to 58%. SDG 6 aims for universal WASH access by 2030, but low-income countries' high open defecation rates threaten this goal. Progress is uneven: Latin America, Caribbean, and East/South East Asia still have significant open defecation, while North Africa and West Asia have largely eliminated it.

The United Nations Sustainable Development Goal #6 aims to ensure availability and sustainable management of water and sanitation for all by 2030, addressing the global crisis where 2 billion people lack access to safe drinking water and 3 billion lack basic hand washing facilities; this goal encompasses multiple targets including safe and affordable drinking water, sanitation and hygiene, water quality, water use efficiency, integrated water resources management, water-related ecosystem protection, international cooperation, and community participation, with California facing specific challenges including contaminated water in rural communities, water affordability issues affecting 1.6 million households, and severe drought conditions exacerbated by climate change that threaten both water access and groundwater sustainability.

The 193 member states of the UN unanimously adopted the 2030 Agenda for Sustainable Development in September 2015. Target 6.2 calls for countries to end open defecation, ensure everyone has access to a basic toilet, and put in place systems for safe management of excreta, with special attention to women and girls. Washing hands with soap after contact with human waste can reduce diarrheal diseases by 40% and respiratory infections by 30%. Diarrhea and respiratory infections cause among the highest number of child deaths in India, and children who survive frequent diarrhea attacks are vulnerable to malnutrition and infections like pneumonia, which affects cognitive development and learning.

Ecological sanitation or Eco-San is a sustainable system for handling human excreta by using dry composting toilets. Such Eco-San toilets not only eliminate wastewater generation but are also practical, hygienic, efficient, and cost-effective. The natural fertilizer produced from recycled human excreta is used in fields as an excellent substitute for harmful chemical fertilizers.

Decentralized ecological sanitation encompasses multiple technologies including composting toilets with chamber systems, evapotranspiration basins for wastewater treatment, and filtration systems. Composting toilets separate liquid and solid waste, with solids covered by material and decomposed over time. Evapotranspiration basins of approximately 4 square meters can serve families of four. These systems preserve water resources, reduce state investment in centralized infrastructure, and produce high-quality compost as a byproduct. Implementation requires adapting technologies to local conditions, including soil type and territorial characteristics, and can serve communities of 30-50 families.

Conventional toilets require significant water for flushing, contributing to water waste. EcoSan (Ecological Sanitation) toilets provide water-free alternatives using dry composting technology. These systems transform human waste into safe, usable resources without contaminating groundwater. Benefits include: preventing groundwater contamination, producing biogas as fuel, and creating natural fertilizer. EcoSan toilets are now implemented in airports, public buildings, and rural communities worldwide including India, Sri Lanka, and the Philippines.

Ecological sanitation encompasses diverse technologies beyond simple 'dry toilets.' Dry toilets (letrinas) dig holes for waste deposition, commonly used in rural areas. Composting toilets emerged in Vietnam due to high water tables, featuring dual chambers for processing. Urine separation is crucial because urine contains 80% water and 20% solids, making it valuable for nutrient recovery. Living toilets (baños vivos) integrate multiple techniques, using biocameras with double-floor systems and ventilation tubes to accelerate fermentation. Biodigesters use aerobic digestion for communities, capturing methane for cooking while producing enriched sludge. Biofilters and artificial wetlands treat water-based systems while recovering nutrients. The key is understanding that ecological toilets require proper maintenance and that the error is often attributed to the system when actually the problem lies in how it is used.

Ecological Sanitation (Ecosan) toilets are sustainable sanitation systems that separate urine and feces collection, using no water for flushing; they employ natural decomposition processes with absorbent materials like ash, lime, sand, or sawdust to convert human waste into safe compost fertilizer, making them suitable for water-scarce coastal and arid regions while preventing environmental pollution.

Wastewater-based epidemiology is a public health surveillance method that analyzes sewage samples to detect and monitor disease prevalence in communities, offering a cost-effective, non-invasive alternative to individual testing that can provide early warnings of disease outbreaks and track population-level health trends.

This extensive segment demonstrates how wastewater surveillance provides real-time community health monitoring across North America. Canada showed moderate CO levels, low Flu A, moderate Flu B, and high RSV. California sites displayed medium CO with slight increases, while the West Coast generally showed lower activity compared to Midwest and Northeast regions. Northwest Washington exhibited influenza B peaking, HMPV rising, and norovirus elevated. Michigan approached baseline levels with all indicators declining. Boston showed medium CO with slight increases, elevated RSV, and high influenza B. New Orleans displayed medium CO declining, high RSV and influenza B both declining, but HMPV rising. This multi-pathogen approach enables early detection of emerging threats before clinical cases surge, supporting proactive public health interventions.

Wastewater-based epidemiology (WBE) is a surveillance method used for decades to track diseases and drugs in natural environments. The fundamental assumption is that patients shed viruses in their biological waste, which can be detected in sewage systems. WBE has been historically used to track polio and has proven effective for SARS viruses and COVID-19. People begin shedding the coronavirus in stools approximately 3-4 days after infection and continue for about 4 weeks, making wastewater testing highly sensitive for population-level surveillance. Cities like Paris and Australia have successfully used WBE to detect virus presence even when individual case numbers are low. For meaningful results, testing should be conducted at smaller geographic scales such as individual wards rather than large sewage treatment plants.

Wastewater testing represents a sophisticated approach to pandemic monitoring that detects viral genetic signals (RNA) rather than live virus particles. The absence of infectious virus in sewage, combined with the strong correlation between wastewater signals and clinical case numbers, enables early warning detection up to one week before confirmed cases emerge. This methodology supplements clinical testing by providing community-level surveillance data. However, implementation challenges persist globally, particularly in regions lacking adequate water infrastructure, requiring international collaboration to expand surveillance capabilities while addressing fundamental water access inequalities.

Wastewater-based epidemiology (WBE) is a powerful public health tool that analyzes substances excreted in human waste to monitor population-level consumption patterns and detect emerging health threats in real-time, as demonstrated by its successful application during the COVID-19 pandemic for virus tracking and its growing use for monitoring drug consumption, including new psychoactive substances (NPS), opioids, and crack cocaine, providing objective, timely data that complements traditional surveillance methods.