1.3 Climate Resilient Sanitation

Climate-resilient sanitation needs not only to adapt to changing climate conditions but should also contribute to mitigate GHG emissions. In this way it enhances people’s health, the resilience of communities, and it contributes to a sustainable living environment.

• Adaptation to changing climate : Climate-related changes in water availability often have a negative impact on sanitation systems. Extreme heat can negatively impact functioning of user interface/containment (e.g. limiting microbial growth in composting toilet or worms in vermicompost toilets); sewer system through corrosion due to increased production of hydrogen sulphide and biological treatment processes. Flooding, for instance, can impact the functionality of onsite sanitation systems or even destroy them and contaminate water resources. Flooding could impact drainage and transport systems, preventing service vehicles accessing onsite sanitation systems to empty their contents; sewer overflows and damage to treatment facilities (typically located in low lying areas near to water bodies. Water stress can also lead to systems dysfunction, affecting water quality and availability. It can then render systems inoperative and force communities back to practices like open defecation.
• Health and contamination risks: Sanitation systems, impacted by climate hazards as flooding or drought, impose significant health and contamination risk. People most affected are poor families, women, girls and persons with disabilities.
• Mitigation to climate change: Sanitation systems contribute a significant amount of GHG emissions and by adopting climate-resilient approaches the sanitation sector can contribute to the global climate goals. Simple examples are the substitution of fossil fuels by renewable energy sources, reduction of methane emissions from septic tanks or a local low-emission procurement.

An increasing number of people live in extreme heat, water stressed or flood-prone areas, a problem that is rapidly increasing as a result of climate change. Households that have gained access to basic or safely managed sanitation systems risk losing them in the event of climate-related disasters, changing climate patterns and sea level rise if due care is not taken in the planning and development of such systems and consideration is not given to mitigating potential risks and shocks. Access to sanitation is a human right. It provides benefits across society in improved health as well as economic and social development. Making sanitation resilient is in the best interest of everybody. According to Intergovernmental Panel on Climate Change (IPCC), key sanitation infrastructure systems will be increasingly vulnerable if design standards do not account for changing climate conditions. Non-climate-resilient sanitation services pose a substantial public health hazard. During more frequent and severe flooding, damaged toilets and sanitation systems have spread disease across entire communities. In drought-affected areas, non-resilient sanitation systems can exacerbate water stress or cease to function, causing families to revert to open defecation. This impact is greatest on the most vulnerable individuals, especially women and girls and persons with disabilities. Unless urgent actions are taken, the impact of climate change is set to undermine decades of progress in the sanitation sector. Systems and services must be made resilient to protect investments, promote public health and ensure universal access to sustainable, equitable and safe sanitation for all. Furthermore, safe use of sanitation wastewater and sludge from sanitation systems for irrigation and energy recovery has a large unmet potential to contribute to adaptation and mitigation in the agriculture and energy sectors. A study (UNICEF, 2020) estimated that $105 billion per year is needed to achieve the sanitation component of SDG target 6.2 by 2030 and additional amounts are required to adapt to impact of climate change. Sanitation especially is often underfunded at the country level and is failing to take advantage of climate funding opportunities, with less than 1% of major climate funding being allocated to the sanitation sector. Emissions from sanitation systems are often underestimated, and global estimates do not always consider the non-sewered sanitation systems which are prevalent in rapidly growing cities in low-and middle-income countries. The global methane emissions from non-sewered sanitation systems in 2020 was estimated at 4.7% of global anthropogenic methane emissions, which are comparable to the GHG emissions from wastewater treatment plants (Cheng S. et al., 2022). A recent study found that in an African city, sanitation systems may account for as much as half of all city-level emissions. Yet approaches to balance cost effective access to resilient sanitation for all and lower emissions are not yet clear and projects to mitigate these emissions remain small in number. The sanitation sector in most countries must be supported to put emphasis on climate adaptation and mitigation and the opportunities for building resilience or achieving mitigation goals are incorporated as part of routine programming. There is an urgent need for the sector partners to mainstream adaptation and mitigation measures in sanitation programming. (Climate Resilient Sanitation Coalition, 2022)