Around 55% of the world’s population lives in urban areas, a proportion that is expected to increase to 68% by 2050.
New challenges for sanitation and wastewater and fecal sludge management place growing pressure on policymakers and industry professionals, and investment and innovation in this sector has become critical.
The need for climate adaptation interventions, alongside digital technology use for the improvement of service management, are two key trends that have emerged as solutions to address these growing challenges in global sanitation and wastewater management.
By Marta Koch, UCL Engineering for International Development Centre, University College London
UN-Habitat’s ‘Global Report on Sanitation and Wastewater Management in Cities and Human Settlements’ was launched at the Second UN-Habitat Assembly in Nairobi, Kenya, in June 2023 in honor of the UN International Decade for Action for Water for Sustainable Development (2018-2028) and the Water Action Agenda.
The report, prepared by a consortium led by Water & Sanitation for the Urban Poor (WSUP), and supported by Agence Française de Développement and the Bill & Melinda Gates Foundation, aims to provide professionals and policymakers working at the intersections of water, the environment, health, energy, agriculture, spatial planning, and land use with a global cooperative and cross-sectoral reference on the current situation and developments in sanitation and wastewater and fecal sludge management in cities and human settlements.
In a foreword to the report, Maimunah Mohd Sharif, Under-Secretary-General and UN-Habitat Executive Director, highlights the need to “develop more sustainable and resilient cities and communities by taking a more comprehensive approach… while encouraging environmental sustainability and preserving public health” as the world marks the halfway point to the 2030 deadline for implementing the SDGs. As Sharif notes, wastewater is increasingly being “viewed as a resource, not a waste stream,” and this paradigm shift is creating timely opportunities for the development and application of novel sanitation and wastewater management systems.
The report’s key findings from data gathered from existing literature and through primary data collection across 18 cities in Africa, Asia, Europe, the Middle East, Latin America, the Caribbean, and North America highlight the recent developments and problem-solving potential of climate-resilient initiatives and digital innovation across the sector globally. Around 55% of the world’s population lives in urban areas, a proportion that is expected to increase to 68% by 2050. Projections show that urbanization, the gradual shift in residence of the human population from rural to urban areas, combined with the overall growth of the world’s population, could add another 2.5 billion people to urban areas by 2050, with around 90% of this increase taking place in Asia and Africa. As a result of these urban developments, new challenges for sanitation and wastewater and fecal sludge management place growing pressure on countries to invest in physical and digital infrastructures and implement urgent service provision improvements.
The report emphasizes the increasing importance of structural and non-structural interventions in climate adaptation and risk mitigation as droughts, flooding, and sea level rise continue to cause damage to sanitation infrastructure. Non-structural adaptation measures include planning, institutional, and regulatory arrangements such as revising master plans, community training sessions, capacity building for sanitation system managers, and improving public awareness. For instance, the report highlights eThekwini Water & Sanitation Company’s adoption of resource-efficient technologies in South Africa and their use of a resource recovery demonstration facility which produces 30% less sludge, uses 30% less energy, and has a 50-75% smaller physical footprint than conventional treatment works.
Structural intervention measures include constructing improved sanitation facilities to hygienically separate excreta from human contact, implementing water-saving and reuse-oriented sanitation systems, and separating stormwater from wastewater, as done in the UK. Digital infrastructure improvements include developing effective climate resilience information and monitoring systems. Case studies from cities like Hanoi in Viet Nam and Shanghai in China illustrate climate-resilient urban drainage systems, emphasizing a ‘blue, green, and grey’ infrastructure approach involving water-sensitive urban design, integrated flood control planning, and decentralized infrastructure as key components.
Despite the sanitation sector’s exposure to climate risks, it is still not a major component of Nationally Determined Contributions (NDCs) under the Paris Agreement on climate change that reflect countries’ priorities for reducing national emissions and climate change adaptation. Only a small percentage of NDCs, mostly in the Middle East and North Africa (MENA) region and sub-Saharan Africa, focus on sanitation and wastewater management, the majority addressing other water-related activities. US data show that wastewater managers are aware of climate change but often perceive it as a distant threat. Furthermore, sanitation services receive only a small share of climate financing, and lack of understanding among stakeholders about how climate financing schemes work is a key barrier to accelerating innovative sanitation service adaptation measures.
In addition, the report emphasizes the growing importance of data systems as key drivers for improving global sanitation services. Notable examples from South America and Africa include the National Data Management Entity (DANE) in Medellin, Colombia, and the CWIS-SAP tool in Nakuru, Kenya, which aim to provide accurate monitoring information on wastewater and fecal sludge treatment processes to bridge the data gap.
To ensure effective data collection and use, the integration of data infrastructure platforms into wider policy frameworks, institutional planning, and financial systems and feedback loops via a holistic approach is imperative. There has been a global rise in the use of tools to improve customer-utility relationships, data acquisition and integration, network infrastructure and connectivity, data processing and storage, management, and analytics. Interestingly, the COVID-19 pandemic has been noted as having acted as a positive catalyst for digital revenue collection in the sector.
However, digitization initiatives for collecting, analyzing, and disseminating sanitation data must be viewed in the broader context of addressing key financial, technological, and socioeconomic barriers. Financial barriers include lack of financial resources, inappropriate funding allocation, and lack of clarity on return on investment for public-private partnerships (PPPs). Technological barriers include technological complexity, cybersecurity concerns, and IT failures, while key socioeconomic barriers include resistance to change, decentralized governance system challenges and political and community opposition.
The report recommends urgent action in support of climate mitigation initiatives and digital innovation throughout the sanitation service chain via further peer-to-peer learning and South-South cooperation in order to replicate best-fit case studies of cities leading in green and digital solutions in other global contexts. There is a need to invest more smartly in collaborative research, technologies, and service models adapted to suit different contexts and their associated data and climate change risks as well as socioeconomic barriers.
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Marta Koch is a researcher at the UCL Engineering for International Development Centre at the Bartlett School of Sustainable Construction, University College London, and co-author of UN-Habitat’s ‘Global Report on Sanitation and Wastewater Management in Cities and Human Settlements’ (2023).