Abteilung Siedlungshygiene und Wasser für Entwicklung

Citywide Inclusive Sanitation (CWIS)

CWIS markiert einen Paradigmenwechsel in der städtischen Abwasserentsorgung und rückt Gerechtigkeit, öffentliche Gesundheit, Umweltschutz sowie die Koexistenz hybrider Abwassersysteme in den Fokus. Dieses Konzept befindet sich in kontinuierlicher Weiterentwicklung, wobei Forschung und Praxis sich gegenseitig befruchten. Ziel ist es, einen Konsens zu schaffen, indem wichtige Akteure des Sektors wie die Weltbank, die Gates Stiftung, NROs wie WaterAid, sowie andere zusammengebracht werden, um ihre Anstrengungen an einer gemeinsamen Front zu bündeln.

Sandec nimmt bei der Forschung im Bereich der städtischen Abwasserentsorgung eine führende Rolle ein, und mehrere Projekte tragen zur CWIS-Initiative bei. Die folgenden Projekte haben einen direkten Bezug

CWIS Planung

Im Rahmen dieses Projekts wurde eine innovative Planungsmethodik namens "Bridged Approach to Inclusive Planning (BAIS)" entwickelt. Diese Methodik zielt darauf ab, die städtische Abwasser­entsorgung für Städte in Entwicklungsländern nach den CWIS-Prinzipien zu planen. Sie verbindet Top-down- und Bottom-up-Planungsansätze für unterschiedliche sanitäre Kontexte. Projektschwer­punkt liegt in Indien, wo die Abwasserentsorgung höchste Priorität hat, sowie in anderen Ländern südlich der Sahara und in Lateinamerika nimmt diese Forschung eine ganzheitliche Perspektive auf die Planung für CWIS ein.

>> Lesen Sie die Doktorarbeit zu diesem Thema:

Planning citywide inclusive sanitation. Mapping the paradigm shift in the Global and Indian context

Sanitation is fundamental to a city’s health, liveability, and social and economic development. Yet, as the world continues to urbanise, progress in urban sanitation is outpaced by rapid urbanisation and population growth. Today, about 40% of the world’s urban residents do not have safely managed sanitation, with a vast majority of them are living in low- and middle-income countries (LMICs). In the last five decades, numerous international development agendas on urban sanitation have been set and failed to reach the expected sanitation outcomes in LMICs. Reasons for this failure include poor planning, narrow infrastructure focussed approach, inadequate consideration of contextual factors, lack of attention to policy and institutions, and absence of community involvement. [...]

Die Abwasserentsorgung ist von grundlegender Bedeutung für die Gesundheit, die Lebensqualität sowie die soziale und wirtschaftliche Entwicklung einer Stadt. Doch während die Welt immer weiter verstädtert, werden die Fortschritte bei der städtischen Abwasserentsorgung durch die rasche Urbanisierung und das Bevölkerungswachstum überholt. Heute verfügen etwa 40 % der Stadtbewohner weltweit nicht über eine sichere Abwasserentsorgung, wobei die überwiegende Mehrheit von ihnen in Ländern mit niedrigem und mittlerem Einkommen (LMICs) lebt. In den letzten fünf Jahrzehnten wurden zahlreiche internationale Entwicklungspläne für die städtische Abwasserentsorgung aufgestellt, ohne dass die erwarteten Ergebnisse in den LMICs erreicht wurden. Zu den Gründen für dieses Scheitern gehören schlechte Planung, ein eng auf die Infrastruktur ausgerichteter Ansatz, eine unzureichende Berücksichtigung kontextbezogener Faktoren, mangelnde Aufmerksamkeit für Politik und Institutionen sowie eine fehlende Einbeziehung der Bevölkerung. [...]
Sankara Narayan, A. (2022) Planning citywide inclusive sanitation. Mapping the paradigm shift in the Global and Indian context, 182 p, doi:10.3929/ethz-b-000561822, Institutional Repository

Entwicklung von Kapazitäten

Das ConCaD Projekt hat zum Ziel, die Beratungskapazitäten des Privatsektors für die Planung, Gestaltung und Umsetzung einer flächendeckenden, inklusiven Abwasserentsorgung auszubauen. Durch den Ausbau der Beratungskapazitäten sollen die Bereitstellung und Nachhaltigkeit von Sanitärdienstleistungen für alle verbessert werden. Zudem soll die Wirkung von Investitionen in die Sanitärversorgung auf städtischer Ebene in Afrika und in Südasien erhöht werden, wobei der Fokus auf groß angelegten Programme der Siedlungswasserwirtschaft liegt, die von Regierungen und/oder internationalen Finanzierungsinstitutionen und Entwicklungspartnern finanziert werden.

Towards CWIS Series (Auf dem Weg zu CWIS)

Die Video-Serie Towards CWIS Series porträtiert afrikanische und asiatische Städte, die sich auf dem Weg zu einer stadtweiten inklusiven Abwasserentsorgung befinden. Abwasserexperten aus Kampala (Uganda), Lusaka (Sambia), Kathmandu (Nepal), Abidjan (Elfenbeinküste) und Dhaka (Bangladesch) erzählen die Geschichte der Abwasserentsorgung in ihren Städten, gewähren persönliche Einblicke in ihre Arbeit, liefern Hintergrundinformationen über die aktuelle Situation der Abwasserentsorgung und teilen ihre Visionen. Sektor Innovationen werden dabei besonders hervorgehoben.

Publikationen und Berichte

Einige ausgewählte Veröffentlichungen zu diesem Thema:

Lüthi, C.; Sankara Narayan, A. (2018) Citywide inclusive sanitation: achieving the urban water SDGs, In: Camarena, L.; Machado-Filho, H.; Casagrande, L.; Byrd, R.; Tsakanika, A.; Wotton, S. (Eds.), Urban waters - How does water impact and is impacted by cities and human settlements?, 11-13, Institutional Repository

Solving urban sanitation - sustainably and equitably

Citywide Inclusive Sanitation (CWIS) is gaining traction as an integrated approach that can achieve multiple United Nations Sustainable Development Goals (SDGs). Abishek S. Narayan and Christoph Lüthi at the Department of Sanitation, Water and Solid Waste for Development (Sandec) at the Swiss Federal Institute of Aquatic Science and Technology (Eawag) in Zurich, Switzerland, explain the concept and its implementation through current projects.
Narayan, A. S.; Lüthi, C. (2020) Solving urban sanitation - sustainably and equitably, World Water, 43(4), 18-21, Institutional Repository

Social network analysis for water, sanitation, and hygiene (WASH): application in governance of decentralized wastewater treatment in India using a novel validation methodology

Social network analysis (SNA) is a versatile and increasingly popular methodological tool to understand structures of relationships between actors involved in governance situations. Given the complexity of the set of stakeholders involved in the governance of Water, Sanitation and Hygiene (WASH) and the diversity of their interests, this article proposes SNA to the WASH sector. The use of SNA as an appropriate diagnostic tool for planning Citywide Inclusive Sanitation is explored. Missing data is a major problem for SNA in the studies of governance situations, especially in low- and middle-income countries. Therefore, a novel validation methodology for incomplete SNA data, relying on information from internal and external experts is proposed. SNA and the validation method is then applied to study the governance of decentralized wastewater treatment in four cities of India. The results corroborate key differences between mega and secondary cities in terms of institutions, community engagement and overall sanitation situation including aspects of decentralized wastewater treatment plants, based on the city types.
Narayan, A. S.; Fischer, M.; Lüthi, C. (2020) Social network analysis for water, sanitation, and hygiene (WASH): application in governance of decentralized wastewater treatment in India using a novel validation methodology, Frontiers in Environmental Science, 7, 198 (18 pp.), doi:10.3389/fenvs.2019.00198, Institutional Repository

The clean plan: analysing sanitation planning in India using the CWIS planning framework

Sanitation in India has received national attention for over a decade, especially with the Swachh Bharat Mission (SBM) making it a political priority. However, due to the lack of appropriate sanitation planning practices, there have been little long-term gains made in urban sanitation beyond the ending of open defaecation. In this paper, we analyse the key barriers to sanitation planning, in India, in the context of the emerging paradigm of Citywide Inclusive Sanitation (CWIS). A mixed method approach of shit flow diagrams, social network analysis, policy analysis, interviews and workshops at the national, state (2) and city (4) levels was conducted. Eight factors were identified as important barriers for planning including inadequate planning capacities, lack of ownership of city sanitation plans among city governments, poor community involvement, absence of a uniform planning framework, unreliable political and financial support, overlapping jurisdictions, and scheme-based funding. The paper also proposes the CWIS Planning Framework which offers a perspective at overcoming these barriers with the recommendation of bridging top-down and bottom-up planning approaches. While there is increasingly more clarity on what CWIS means, there is little understanding on how to plan for it. Therefore, this framework provides the theoretical basis for planning with the CWIS approach.
Narayan, A. S.; Maurer, M.; Lüthi, C. (2021) The clean plan: analysing sanitation planning in India using the CWIS planning framework, Journal of Water Sanitation and Hygiene for Development, 11(6), 1036-1047, doi:10.2166/washdev.2021.130, Institutional Repository

Regulating citywide inclusive sanitation (CWIS) in Colombia

The conventional top-down scope of relying only on centralised sewerage has proven insufficient to reach the entire global population with safely managed sanitation and meet Sustainable Development Goals 6.2. and 6.3 by 2030. Citywide Inclusive Sanitation (CWIS) has emerged as an approach to accelerate progress by considering different technologies and service provision models within the same city to expand sanitation access equitably and sustainably. However, to generate an enabling environment for CWIS to be implemented successfully, regulatory frameworks must be adapted, as they are often unsuited for non-sewered sanitation solutions. By analysing the Colombian case study through a mixed qualitative methodology comprised of a policy review, semi-structured interviews, and workshops with key stakeholders in the urban sanitation sector, the country's regulatory framework was evaluated to determine if it is adequate to implement CWIS. Regulations were identified to pose barriers for CWIS and produced a disabling environment for its application. This research proposes recommendations to adapt the regulatory framework to allow CWIS application in Colombia based on the encountered barriers. This is the first comprehensive study on regulations for CWIS in the Latin American context and therefore provides the basis for further research to understand the dynamics related to effective regulations for CWIS globally.
Saker, A.; Pedraza, A. B.; Narayan, A. S. (2022) Regulating citywide inclusive sanitation (CWIS) in Colombia, International Journal of Environmental Research and Public Health, 19(9), 5669 (21 pp.), doi:10.3390/ijerph19095669, Institutional Repository

Sanitation potpourri: criteria for planning mix of sanitation systems for citywide inclusive sanitation

Sanitation is a universal need and thus requires universal access. Despite having the world’s largest sanitation campaign, only 37% of urban India has access to safely managed sanitation systems. Due to the heterogeneity of Indian cities, a mix of different sanitation systems is required to meet the demands of these rapidly urbanising cities. The Manila principles on Citywide Inclusive Sanitation (CWIS) propose a mix of technologies as a key pillar in achieving the Sustainable Development Goals on urban sanitation. However, there is a lack of understanding on the criteria to consider when planning the technological options for CWIS. The mega-city of Chennai is chosen as a case study, and mixed methods including a Faecal Waste Flow diagram (SFD), Social Network Analysis (SNA) and interviews are applied. This study then presents a set of 14 contextually relevant criteria for the implementation of sewered and non-sewered technologies in the city. The SFD shows that 35% of Chennai’s faecal waste remains unsafely managed while using SNA identified that the water and sanitation utility, the municipal corporation and the slum clearance board are the best placed stakeholders in the city to create a change in the sanitation situation. Furthermore, 17 drivers and barriers for the implementation of non-sewered technologies are identified. The criteria catalogue was also theoretically tested for an example ward in Chennai. The findings of the study show that a catalogue of physical, technical, institutional and financial criteria is useful for planning a mix of technologies with the CWIS approach.
Mitra, A.; Narayan, A. S.; Lüthi, C. (2022) Sanitation potpourri: criteria for planning mix of sanitation systems for citywide inclusive sanitation, Environment and Planning B: Urban Analytics and City Science, 49(8), 2195-2215, doi:10.1177/23998083221091568, Institutional Repository

There is no environmental health without public health: exploring the links between sanitation and waterbody health in Bengaluru, India

Over 70 per cent of India’s surface water is polluted by human excreta and other waste and less than 35 per cent of urban wastewater is treated. This poses a severe risk to public and environmental health. Urban waterbody rejuvenation in India often focuses on aesthetic improvements rather than addressing its systemic interdependencies with sanitation. This paper establishes these systemic links through a mixed-methods study using water-quality testing and stakeholder interviews in the city of Bengaluru, India. A conceptual system dynamics model of technical, social, institutional and environmental factors is developed. Results show that sewage leaks into lakes via stormwater drains are a major pollution pathway, among others. Three system levers for positive change have been identified: coordination of government entities, adequate faecal sludge management and strong citizen involvement. Citywide inclusive sanitation (CWIS) is proposed as an approach to provide leverage and solve the intertwined issues of public and environmental health.
Sundar Navamany, C. G.; Narayan, A. S.; Scholten, L. (2022) There is no environmental health without public health: exploring the links between sanitation and waterbody health in Bengaluru, India, Environment and Urbanization, 34(1), 76-98, doi:10.1177/09562478221084243, Institutional Repository

Es wurde eine Sonderausgabe zum Thema "Citywide Inclusive Sanitation" zusammengestellt, und mehrere Artikel wurden in der internationalen Fachzeitschrift "Frontiers in Environmental Science" veröffentlicht.

Diese Artikel sind frei zugänglich unter www.frontiersin.org/research-topics/9491/city-wide-sanitation-the-urban-sustainability-challenge