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The enabling environment for citywide water service provision: Insights from six successful cities


Equitable access to safe drinking water remains a key challenge in many urban areas of low- and middle-income countries. This study aimed to characterize the enabling environment for inclusive urban water service delivery, and specifically to elucidate the institutional arrangements, policies, regulations, service delivery approaches, financing models, and surrounding contextual factors that influence progress. We identified six cities across Africa, Asia, and South America that offered historical examples of success in inclusive piped water provision, resulting in high levels of access and service quality, including within low-income areas. Using a modified form of the social-ecological systems framework to structure our investigation, we conducted a comparative case study analysis to learn from these cities. Our analysis focused on a review of existing case-specific literature, supplemented by interviews with 1–3 key informants per case to update or fill gaps in the literature. A variety of characteristics supported safe and inclusive services, with contextually appropriate strategies depending on existing institutional arrangements, infrastructure, and the surrounding social, economic, political, and environmental context. Our study cities illustrated three types of progress–utility-driven, regulator-supported, and municipality-driven–each characterized by specific features and drivers of success. We also identified 12 characteristics making up the enabling environment across all three types. These characteristics highlighted two broad themes. First, a well-functioning water service provider was often a prerequisite for inclusive, pro-poor service provision. Elements such as clear performance indicators, customer feedback mechanisms, and strategies to sustainably finance operating costs contributed to cities’ success. Second, inclusive water services often required explicit pro-poor policies and strategies, such as the removal of land tenure requirements for piped connections and community mobilization for participatory decision-making. Although the importance of specific characteristics will vary depending on context, our analysis offers a common foundation to guide progress toward universal access to safe water.

1. Introduction

Achieving and sustaining equitable access to safe drinking water remains a key challenge in many urban areas of low- and middle-income countries (LMICs), especially in view of continued urban expansion and the threats posed by climate change [1]. In 2020, an estimated 42% of urban residents in low-income countries did not have access to safely managed drinking water, and these average levels masked wide disparities across household income levels [2]. For example, while 95% of the richest urban residents in Uganda had access to at least basic drinking water service in 2017, only 53% of the poorest residents did [2]. Additionally, urban water access levels in some countries (such as Niger and Pakistan) have stagnated or fallen since 2000, while rural access has improved [2, 3]. Future trends in population growth, urbanization, and increasing pollution will likely exacerbate these issues [4]. Sustaining equitable improvements in safe urban water access requires an understanding of the enabling environment and best practices from similar settings. In particular, the enabling environment consists of relevant policies, regulations, institutional arrangements, financing approaches, and additional contextual factors that influence the actors and infrastructure responsible for delivering water to residents [5].

A number of contextual factors may contribute to non-inclusive and inequitable urban water provision that does not adequately serve low-income populations. These include persistent colonial-era arrangements, where infrastructure development favors a small, privileged class living in a city’s inner core [6]. The exclusion of low-income populations from formal private property and rental markets can drive unplanned urban expansion into the peripheral and marginal areas that remain available for informal development [1, 3, 7]. Unstable or flood-prone soils, shallow groundwater tables, unfavorable topography or geology, high-density housing, and uncertain land tenure often characterize these locations, hindering the installation of conventional piped networks and increasing pollution risks [3, 79]. Those without access to the network typically rely on small-scale providers, who might operate private boreholes or resell tap water, often at prices higher than those of piped services–paradoxically requiring the most vulnerable households to pay more than wealthier residents for water that may be of lesser quality [1, 6, 10].

The local enabling environment is foundational to the development, operation, and outcomes of service provision approaches, including their effectiveness, inclusivity, and sustainability. Broadly speaking, what may be most useful for today’s decision-makers is an overall understanding of the enabling environment for urban drinking water across a variety of geographic, governance, social, political, economic, and environmental contexts [11]. Previous research has often focused on the challenges and opportunities associated with individual aspects of the enabling environment, such as water policies for informal settlements, cost recovery, or privatization [3, 6, 10, 12]. Among more comprehensive analyses of enabling environments, few have captured multiple countries [13, 14]. Both approaches leave room to better characterize the enabling environment for urban drinking water and draw parallels across diverse contexts. Specific considerations that require further study include the identification and application of appropriate pro-poor mechanisms across different service provision and regulatory environments and the roles of foreign aid and consumer tariffs in balancing financial sustainability with affordability [1, 3, 6, 10, 1517].

Accordingly, the objective of this study was to learn from diverse historical examples of improvements in inclusive, citywide delivery of piped water services in LMICs. Specifically, we sought to answer the following research question: What policies, regulations, institutional arrangements, and contextual factors have historically driven inclusive improvements in urban piped water access in lower-income countries? We focused on piped water because it is typically considered to be the highest standard of service [1, 18]. Based on existing literature and knowledge, we hypothesized that inclusive, citywide improvements in safe and affordable water provision require institutional, regulatory, and policy frameworks that specify clear mandates and strategies for reaching the poor. Additionally, we hypothesized that many factors beyond formal policies–such as community participation, environmental shocks, and champions (i.e., individuals who proactively drive institutional or sector-wide reforms)–influence the effectiveness and sustainability of these improvements. To answer our research question, we conducted a comparative case study analysis of six successful examples of citywide piped water service from various contexts. While we did hypothesize that the enabling environment would have certain general characteristics, we employed an inductive approach to allow for the possibility that additional features may emerge from our analysis.

2. Materials and methods

2.1. Conceptual framework for analysis

In this study, we used a modified form of the social-ecological system (SES) framework to structure our analysis and characterize the urban water sector [11, 19]. Conceptual frameworks such as the SES framework can aid in categorizing key components and their relationships [11, 20, 21]. The SES framework originally emerged from studying governance of common-pool resource systems such as forests and fisheries and built upon the earlier Institutional Analysis and Development (IAD) framework [2022]. For this study, we chose to employ the SES framework rather than others such as the IAD framework because the SES framework has a more explicit focus on contextual factors related to social, economic, political, and ecological conditions and resources [21]. This feature was especially useful, as we expected such contextual factors in our six cases to substantially influence the enabling environment for water service provision, regulation, and progress toward greater access and equity. The SES framework has been revised, adapted, and applied across multiple sectors, including by one of this study’s authors for urban water and sanitation [11, 19, 21, 23]. For this work, we modified the framework slightly to focus on the characteristics of governance structures, relevant actors, service delivery approaches, socioeconomic and political context, and environmental context (Fig 1).

Fig 1. A version of the social-ecological systems (SES) framework modified to focus on governance, actors (e.g., service providers, regulators, policymakers, consumers), and contextual factors, adapted from previous work of one of this study’s authors [11].

The five categories of the modified SES framework provided the basis for our comparative case study analysis. The Governance category defines rules and conditions under which actors and service delivery approaches operate [11]. At their core, these governance structures involve laws, statutes, policies, and institutional arrangements that organize water and sanitation service delivery and regulation. Actors participate in numerous ways, including as service providers, regulators, policymakers, and consumers [11]. Relationships across these actors are connected with the roles and responsibilities defined through governance structures. Service delivery approaches designate the infrastructure, technologies, and types of services that deliver water, including piped or non-piped provision [11, 19]. The previous three categories exist within a broader context that helps to define why elements have evolved in a certain way and what opportunities for improvement are feasible [11]. The social, economic, and political context includes political agendas, economic trends, and social norms. Finally, the environmental and resource context recognizes that water services are closely linked with local ecosystems and global climate change, with factors such as water scarcity, groundwater table depth, soil types, and pollution affecting decisions regarding water sources, treatment and distribution approaches, and conservation measures [11, 19].

2.2. General literature review on the enabling environment for urban water service improvements

To begin our process of understanding the enabling environment for urban water provision, we reviewed existing peer-reviewed and grey literature concerning urban water provision, quality, policies, governance, pro-poor mechanisms, and related topics (e.g., [1, 3, 6, 810, 12, 17, 18, 2443]). Search terms used to identify literature resources included “urban water,” “water policy,” “urban drinking water quality,” and similar phrases. We also included additional resources referenced in key papers from the searches, as well as those recommended by experts interviewed during the case identification process (see Section 2.3). Generally, we focused on materials published within the past 10 years (over 80% of reviewed references were published after 2012), aiming to develop a picture of the current body of knowledge. We categorized literature findings according to the SES framework, separating well-established knowledge from unresolved debates (Tables A and B in S1 Text; these tables also identify relevant second-tier variables from the original SES framework [21]). This literature review provided a lens for our subsequent case study analysis.

2.3. Case study identification and selection

For our comparative case study analysis, we selected six cities from low- and middle-income countries that have demonstrated historical success in providing inclusive city water services. This number of cases allowed us to capture wide-ranging contexts while also exploring the details of each city in depth. Our identification and selection process involved three steps, described in detail below: (i) shortlisting candidates based on expert interviews and literature review; (ii) screening shortlisted candidates for eligibility; and (iii) selecting a subset of eligible candidates to capture a diversity of contexts (Fig A in S1 Text). As described below, the first two steps represented a two-pronged approach in which we balanced the nuanced (but subjective) information provided by expert knowledge with the objective (but less nuanced) data used for screening.

We shortlisted 18 candidate cities based on seven expert interviews and our review of existing literature (Section 2.2). Experts interviewed were individuals having several years of experience working and conducting research in the international urban water sector, and each individual provided verbal consent to contribute to the study (Table C in S1 Text). Interviews were unstructured and began with the following prompt: “What cities do you know that have made meaningful progress toward safe water for all?” During each discussion, we intentionally kept the definition of “meaningful progress” broad to allow for various forms of progress and success, though we probed on specific topics such as water service coverage levels, water quality, reliability, non-revenue water, cost recovery, and affordability [1, 10]. We also specified that we were particularly interested in progress with regard to equity and inclusion of low-income urban residents [1], emphasized in the original prompt with the phrase “for all.” Additionally, we asked interviewees about specific cities that were identified in the literature, if they did not surface naturally during the conversation, and we reviewed additional resources recommended by interviewees if we had not previously identified them through our literature searches.

After shortlisting, we removed five cities that did not meet our eligibility criteria due to (i) a lack of demonstrated citywide improvements in service provision, or (ii) a relatively high economic level during the time of improvements. In terms of improved service provision, we focused primarily on coverage of on premises piped water in each city’s subnational region, as reported by the Joint Monitoring Programme (JMP). This dataset provided a consistent indicator associated with a representative sample of the population across time and across contexts. While considerations such as water quality, reliability, and affordability are also critical elements of successful service delivery, we were unable to find consistent data across all 18 shortlisted cities. To avoid the possibility of incomplete datasets affecting our selection, we chose to focus on an indicator that was more broadly available (access to on premises piped water).

Accordingly, we required that cities met at least one of the following two conditions, based on available JMP data in subnational regions that contained each city: (i) coverage of piped water on premises was higher than 65%, according to the latest data from 2014–2019 (the specific year varied by country); (ii) average annual improvement in coverage of piped water on premises was above one percentage point per year from the earliest (2000–2006) to the latest available data (2014–2019). We also consulted other literature to confirm the trends observed in the JMP data, as some of the JMP’s subnational regions did not correspond precisely to city boundaries. The first condition employed a coverage threshold of 65% because it was the average across our 18 shortlisted cities, and there was a clear break in the data at this point. Four cities met neither of these conditions (Fig A in S1 Text).

With regard to economic level, we aimed to find examples of success with limited economic resources. Accordingly, we excluded cities where: (i) the country was classified by the World Bank [44] as upper-middle income or higher, both presently and during the period when most water service improvements occurred in the city; and (ii) the country had a gross national income (in constant 2015 dollars) [45] higher than present low- and lower-middle income countries during the city’s period of water service improvements (i.e., larger than 3,590 USD per capita, in constant 2015 dollars). One city met these exclusion criteria (Fig A in S1 Text).

Finally, from the 13 remaining cities, we selected six to represent a diversity of contexts. We first considered city- and national-level characteristics related to demographic, economic, political, and environmental factors, including: city population [46], growth rate of the city’s population [46], national urban informality [47], national democracy index [48], national income level [44], and national water stress [49]. With the aid of principal component analysis, we visualized the distribution of cities across all of these characteristics and identified four clusters with similar features (Fig B in S1 Text). We selected a final set of six cities pulled from all four clusters, with additional consideration for geographic diversity and water service levels. We did not explicitly aim to identify and highlight different forms of progress or specific characteristics associated with distinct modes of service provision and governance. From the cluster defined by large city populations (Fig B in S1 Text), we selected Bangkok (Thailand) as the highest performing city in the cluster with respect to water access, and we also chose Ahmedabad (India) to provide geographic representation from South Asia. From a second cluster defined by rapid population growth and high levels of informality (Fig B in S1 Text), we selected Phnom Penh (Cambodia) and Abidjan (Cote d’Ivoire). In particular, we chose Abidjan over Dakar, another high performer in sub-Saharan Africa, because literature reported that water prices were more affordable in Abidjan [50]. From a third cluster defined by relatively higher national income levels and democracy indices, we selected Porto Alegre (Brazil) due to its high levels of water access and because it provided geographic representation from South America. Finally, from a fourth cluster defined by high water stress, we selected Cairo (Egypt) because of its high performance. This selection process provided our six cities for the comparative case study analysis (Fig C in S1 Text).

2.4. Case study characterization

For each of the six selected case study cities, our analysis focused on a review of existing case-specific literature, supplemented by interviews with 1–3 key informants (Table C in S1 Text). Literature reviews included 26–39 pieces of peer-reviewed and grey literature per case and aimed to provide as comprehensive a picture as possible of institutional arrangements, contextual factors, and other drivers of improvements across all categories of our modified SES framework (Table D in S1 Text). Qualitative interviews with key informants were semi-structured and often focused on filling specific information gaps or confirming and providing updates on the evidence found in existing literature. Key informants were local experts, including staff of utilities or regulatory agencies, government ministry officials, academics, in-country staff of donor agencies or non-governmental organizations, and consultants (Table C in S1 Text). Generally, we identified key informants by emailing local institutions that the literature showed to be important players in the context. Interviews took place virtually in English, French, or Portuguese (with translation) and lasted 30–90 minutes, with each interviewee providing verbal consent to participate in the study at the start of the interview. From the literature and interviews, we developed for each case: (i) a timeline of key events (Figs D through I in S1 Text); (ii) an institutional map characterizing roles, responsibilities, and relationships among key actors [25] (Fig 2; Fig J in S1 Text); and (iii) a case narrative describing important elements associated with each category of the modified SES framework (Table D in S1 Text). In particular, the institutional maps, constructed using methods described by Rahman et al. [25], were complementary to the SES framework. These maps enabled us to visualize roles, responsibilities, and relationships across key actors.

Fig 2.

Examples of institutional maps [25] associated with each of the three types of progress: (a) Utility-driven: Phnom Penh; (b) Regulator-supported: Cairo; (c) Municipality-driven: Ahmedabad. Fig J in S1 Text shows institutional maps for the remaining three cases.

2.5. Comparative case study analysis

Using these three elements (timelines, institutional maps, and case narratives) as inputs, we tabulated case information and performed a comparative analysis, using a process of inductive theory building [51] to identify common or contrasting elements and drivers of success across the six cases (Tables E through I in S1 Text). Within each SES category, we qualitatively characterized how each case resonated with key literature themes and knowledge gaps (Tables A and B in S1 Text). We also specified any additional key elements that surfaced from each case, beyond the existing topics described in the general literature. Within each SES category, we also identified those elements that appeared to be especially critical in enabling, supporting, or driving progress in urban water service provision during each case’s period of improvement, with special emphasis on equity and inclusion for low-income residents. We then used these tables (one for each SES category; Tables E through I in S1 Text) to define patterns, particularly focusing on elements that played a similar role across multiple cases, either generally or in specific types of contexts. Following the example of case study research that contributed to the development of the SES framework [52], we formulated these common elements into characteristics of the enabling environment across cases. As noted when discussing the limitations of this study, we cannot state definitively that these characteristics are necessary or sufficient in different contexts, but they provide a foundation for understanding based on the existing literature and additional insights gleaned from our six cases.

3. Results

3.1. Characteristics of study cities

Our six case study cities were Abidjan (Cote d’Ivoire), Ahmedabad (India), Bangkok (Thailand), Cairo (Egypt), Phnom Penh (Cambodia), and Porto Alegre (Brazil), capturing the continents of Africa, Asia, and South America (Fig C in S1 Text). Four cities were in countries currently classified as lower-middle income (Cambodia, Cote d’Ivoire, Egypt, India). The remaining two were in upper-middle income countries (Brazil, Thailand), though water service improvements had started in periods with lower income levels. The six cities also exemplified a variety of demographic, social, political, and environmental characteristics, such as urban informality and water stress (Table 1). Population estimates in 2018 ranged from approximately 2 million in Phnom Penh to 20 million in Cairo, according to urban agglomeration data from the United Nations’ World Urbanization Prospects [46].

Table 1. Summary of selected case study cities.

LIA: low-income area.

By 2014, all study cities had achieved at least 85% coverage of piped water on premises, with some cities attaining these high levels much earlier, such as Porto Alegre in 1989 and Cairo in 1996. Coverage data specific to low-income areas was limited, but we found 57% coverage of piped water on premises in surveyed low-income areas of Abidjan in 2018 [68] and 60% in Ahmedabad in 2014 [55]. Most of the cities also performed well with respect to financial management and reliability of water services. Based on reported data from 2005 to 2018 (depending on the city; Table J in S1 Text), all cities except Bangkok were recovering at least 99% of operating costs, while all except Ahmedabad provided reliable water at least 20 hours per day. Phnom Penh performed especially well with respect to non-revenue water, which decreased from 72% in 1993 to only 6% in 2006 and has remained low since then (e.g., 8% in 2018) [81]. Non-revenue water among the remaining five cities ranged from 20% to 34% (Table J in S1 Text), similar to a recent global estimate of 30% [84].

Our six cases all exhibited unique characteristics with respect to the enabling environment for urban water service provision, including governance, key actors, approaches to service delivery, and the social, economic, political, and environmental context (Table 2, Figs D through I in S1 Text). Below, we describe the findings from our comparative analysis on how these enabling environments contributed to success in these cities. First, we define three overarching types of progress that emerged from the six cases, representing different ways in which certain types of actors and institutional arrangements drove improvements in water access and service quality. Subsequently, we present characteristics, categorized according to our modified SES framework.

Table 2. Key contextual characteristics and drivers of progress across case study cities, categorized according to the modified SES framework.

Empty cells indicate a lack of available data related to the corresponding SES category in a given city. Additional details on historical events and conditions can be found in the city timelines (Figs D through I in S1 Text). NRW: Non-revenue water. IBT: Increasing block tariff.

3.2. Types of progress toward inclusive urban water services

From our six cities, we identified three overarching types of progress, distinguished by the kinds and roles of actors that drove and supported water service improvements, as well as the mechanisms for oversight and monitoring (Fig 2, Fig J in S1 Text). We have labeled these types utility-driven, regulator-supported, and municipality-driven (Table 2), each characterized by a distinct set of features and drivers (Fig 3).

Fig 3.

Drivers promoting an effective enabling environment for urban water provision specific to certain types of progress, including utility-driven (A), regulator-supported (B), and municipality-driven (C). For each driver, we note the cities that provided key examples.

3.2.1. Utility-driven.

Bangkok, Phnom Penh, and Porto Alegre provided examples of utility-driven cases. In these cases, proactive utilities with autonomy and strong leadership drove progress through measures such as institutional reforms, increased metering, appropriate tariff increases, and public engagement [8, 17, 59, 65, 67, 83, 8588]. A lack of political interference provided these utilities with freedom to pioneer the reforms that improved services [8, 17, 89, 90]. Rather than independent regulators, the utilities’ internal bodies provided oversight and guidance [66, 78, 82, 83, 91, 92]. Despite being internal, these entities had some degree of separation from operations (Boards of Directors in Bangkok and Phnom Penh, a Deliberative Council in Porto Alegre), with members representing various political and civil society interests [66, 78, 82, 83, 9193]. For example, in Phnom Penh, the Board of Directors included representation from two national ministries, the municipal government, and utility employees [91, 92], while in Porto Alegre, civil society organizations nominated members of the Deliberative Council [66, 82, 83].

The individual cases offered similar but distinctive stories. Bangkok’s story centered on a national financial crisis in 1997, which spurred the utility–the Metropolitan Waterworks Authority (MWA)–to resist political pressure to privatize by instituting a series of reforms that improved efficiency and customer relations [57, 89]. Governor Chuanpit Dhamasiri, who led MWA through this period, later referred to the crisis as a “blessing in disguise” because it prompted the restructuring that supported the utility’s continued success [59]. In Phnom Penh, development partners including the Asian Development Bank and the World Bank documented the effective leadership of Ek Sonn Chan, director of the Phnom Penh Water Supply Authority (PPWSA) from 1993 to 2012, largely crediting him with the utility’s success [17, 24, 59, 91, 94, 95]. Similar to MWA in Bangkok, PPWSA implemented several reforms during Director Chan’s tenure to increase efficiency, transparency, and financial sustainability, after a governmental decree in 1996 granted the utility financial and administrative autonomy. It is worth noting that the beginning of Director Chan’s leadership coincided with the end of the country’s civil war and an increase in foreign assistance, two important factors that likely also contributed to success in improving water service provision. In Porto Alegre, the city’s water department transformed into an autonomous, financially independent, and municipally-owned utility (DMAE) in 1961, which expanded coverage to a high level (>94%) by 1989 [66, 82, 83]. The city’s prominent participatory budgeting process, initiated by the municipal government from 1988 to 2004, was also instrumental in prioritizing and addressing water needs in underserved low-income communities [65, 67, 82, 96].

3.2.2. Regulator-supported.

We identified regulator-supported types of progress in Abidjan and Cairo. Independent regulatory institutions providing strong monitoring and sector coordination were characteristic of this type. In both cities, the utility annually reported water quality, reliability, and financial performance data, among other information, to national-level regulators [50].

Notably, however, both of these cases also saw substantial expansions in piped water coverage prior to the introduction of independent regulators. Given these earlier periods of improvement, we could have alternatively designated these cases as central government-supported, with centralized state agencies driving infrastructure expansion primarily through donor funding. In Abidjan, a national-level utility (Société de distribution d’eau de la Côte d’Ivoire, SODECI) operated under a public-private partnership established when Cote d’Ivoire gained independence in 1960, wherein government agencies were responsible for infrastructure investment and development while the private partner was responsible for operations and maintenance [50, 69]. Eventually, overlapping and unclear responsibilities across state actors led the central government to create the regulator (Office National de l’Eau Potable, ONEP) in 2006. Along with its regulatory role, ONEP also oversaw infrastructure development and asset management, providing an additional degree of public control over SODECI’s private operation of the infrastructure and making the regulator central to the effective functioning of the public-private partnership [9799].

Until 2004 in Egypt, local water and sewer authorities were responsible for delivering services, providing high levels of coverage in Cairo but depending heavily on donor funding [60, 61, 100103]. In that year, the national government restructured the sector to establish a national holding company that managed all water and wastewater assets in the country, with all local authorities converted into subsidiary companies that still provided services. This restructuring also created an independent national regulator (Egyptian Water and Wastewater Regulatory Agency, EWRA) to oversee the companies’ performance, determine standard service levels, and establish performance indicators.[63, 104]–a reform that international donors had been encouraging as early as the 1980s [100102]. EWRA’s monitoring of financial indicators and new tariffs approved by Egypt’s Cabinet of Ministers have improved the sector’s economic performance, with all subsidiary companies in the Greater Cairo Region recovering more than 100% of operating costs in 2018 [63, 79].

3.2.3. Municipality-driven.

Finally, Ahmedabad represented a municipality-driven case, in which the Ahmedabad Municipal Corporation (AMC) was directly responsible for providing water services and used its role as the local government to proactively promote water access through various integrated initiatives. In particular, AMC leveraged property taxes–as opposed to consumption-based tariffs–to finance water services and implemented holistic informal settlement upgrading programs, which incorporated improvements in water provision alongside other urban services [56, 71, 105]. These programs followed directly from AMC’s established urban governance principles, which included a focus on addressing the needs of the urban poor, and from policies at the national and state levels that gave municipalities clear mandates to engage in pro-poor support to fulfill their constitutional responsibilities [56, 71, 74, 76]. Similar to the internal oversight bodies from our three utility-driven cases, AMC had a separate elected wing to monitor performance, impose sanctions, and confer awards concerning the services being provided by the council’s administrative wing [106]. The fact that these elected municipal officials likely received electoral benefits from improvements in pro-poor service provision may have increased their focus on such efforts. Additionally, non-governmental organizations (NGOs) played a major role in holding the municipality accountable during implementation of the upgrading programs. As key implementation partners, they monitored the work of private contractors and trained community leaders in documenting and reporting problems to reduce occurrences of corruption. Partnership between NGOs and public officials also created a culture of mutual respect between different actors and strengthened public commitment to pro-poor service provision [107]. Finally, effective tax collection systems and financial transparency raised the city’s credit rating and enabled the use of municipal bonds to fund infrastructure improvements, further contributing to AMC’s success [71].

3.3. Characteristics of enabling environments for inclusive urban water services

Across all types of progress demonstrated by the six cases, we identified a total of 12 characteristics that contributed to effective enabling environments for successful and inclusive provision of urban water services (Fig 4). These characteristics captured all five categories from our modified SES framework, which we used to guide the analysis. We also employ these categories here to structure our findings.

Fig 4. General characteristics to promote an effective enabling environment for urban water provision across types of progress.

We noted the cities that illustrated each characteristic.

3.3.1. Governance.

Under the Governance category of our modified SES framework, the use of clear performance indicators was critical to monitoring and incentivizing high levels of performance among service providers, regardless of the specific monitoring arrangements employed across all three types of progress (Fig 4) [8, 59, 64]. Performance indicators employed in our cases focused on topics such as coverage, water quality, reliability, non-revenue water, and cost recovery [8, 59, 64]. Service providers typically submitted annual reports to regulators or other oversight bodies, detailing their performance levels relative to the indicators. In Egypt, the regulatory agency also produced its own nationwide reports, which included additional water quality sampling and analysis conducted by its own staff [63].

Beyond external performance indicators, internal accountability mechanisms and incentives for service provider staff also contributed to improved service delivery. Our utility-driven cases such as Bangkok and Phnom Penh put in place clear codes of action and strict penalties for corruption to increase efficiency and transparency, as well as increased employee salaries [8, 69, 78]. Similarly, the utility in Abidjan (SODECI) offered incentives that helped to increase employee motivation, including high salaries, merit-based promotions, training programs, and funds that paid for social activities and assisted with needs such as housing. Furthermore, SODECI reportedly provided employees with stable jobs during periods when the country’s overall job market was unstable [69].

Along with these measures promoting generally high levels of performance among service providers, additional measures supported inclusive, pro-poor water service provision. These mechanisms included subsidies, explicit mandates to serve low-income residents, and the lifting of land tenure requirements for access to piped connections. In our cases, service providers commonly applied consumption subsidies through tariff structures employing some form of social or increasing block tariff, which favored customers with low water consumption [65, 69, 108, 109]. However, existing literature has noted that the poorest residents may not benefit from increasing block tariffs if they are unable to connect to the piped network, household sizes are large, or multiple households share connections [1, 110]. Accordingly, several of our cases have also implemented connection subsidies. In Abidjan, for example, consumption tariffs paid by higher-volume customers cross-subsidized connections for low-income residents. From 1986 to 1998, piped coverage expanded considerably in the city, with 87% of new connections being subsidized [108, 111]. Similarly, Phnom Penh and Ahmedabad implemented connection subsidy programs and have offered installment plans so that residents could pay the fees over time [58, 112]. Additionally in Ahmedabad, key informants described the approach of funding water services through property taxes instead of consumption-based tariffs as inherently pro-poor, since low-income residents typically pay less in property tax.

With regard to clear mandates for low-income service provision and lifting of land tenure requirements, Ahmedabad provided a strong example of both. India’s 74th Constitutional Amendment Act of 1992 outlined 18 responsibilities for local authorities, and policies at the national and state levels provided clear mandates for municipalities to engage in pro-poor support to fulfill these responsibilities [56, 71, 74, 76]. Ahmedabad also developed its own urban governance principles, one of which focused on addressing the needs of the urban poor [74], and the city’s boundaries have expanded multiple times to absorb growing peripheral areas [56, 76, 113, 114]. However, even with clear mandates and pro-poor subsidy programs, existing literature has highlighted that ambiguous land tenure can often remain a critical barrier to piped water connections, especially when households must provide proof of land ownership [3, 15, 17]. Ahmedabad instituted a program removing such land tenure requirements in 2002, called the No Objection Certificate Scheme. This program enabled low-income residents to apply for connections if their house was below a certain size and, critically, if they could provide proof of residency–rather than ownership–through an electricity bill, voter identification card, or other document showing their address [76]. Notably, the Cairo Water Company made a similar shift in 2014, following the city governor’s 2008 statement endorsing the extension of piped networks into areas regardless of legal status [103].

In our cases, these pro-poor measures appear to have been more important in making services more inclusive than constitutional rights to water. Existing literature has shown that explicit rights to water and sanitation, enshrined in national constitutions or other key policy documents, can sometimes be used in court cases to help improve access, although methods for their application may not always be clear [115, 116]. In most of our cases, constitutional rights to water and sanitation did not exist. Brazil did have a constitutional right to water, which has assisted in some legal cases. However, it also conflicted with the right to private property, allowing utilities to continue requiring proof of land tenure when households applied for piped connections and limiting its impact on water access among the poor [117].

3.3.2. Actors.

Under the Actors category, mechanisms for involving city residents–particularly those living in low-income areas–in service delivery, advocacy, and planning activities were critical in promoting inclusive water provision (Fig 4). Community mobilization efforts in low-income areas can take a variety of forms and occur in partnership with utilities and municipalities. In particular, our cases demonstrated examples of political advocacy, delegated management, and participatory budgeting. Existing literature has highlighted that community groups engaging in collective action can increase recognition and progress for low-income areas [15], and we saw similar patterns in Abidjan, Ahmedabad, and Bangkok. Residents of Abidjan’s informal urban settlements, characterized by uncertain legal status, reportedly engaged in efforts to improve services more effectively than legally secure peri-urban fishing villages, in part due to organization through community leaders to develop connections with local government officials [9]. As part of Ahmedabad’s slum upgrading projects, democratically elected neighborhood associations mobilized the necessary finances from within the community, playing an instrumental role in expanding water infrastructure [72, 75, 113]. In Bangkok, low-income community groups worked with the utility to set up what were essentially delegated management models. Locally-elected committees managed the area’s network, collected connection fees and tariffs from residents, paid bulk tariffs to the utility, and used surplus funds to support other community projects [58]. Finally, Porto Alegre’s participatory budgeting processes enabled low-income residents to contribute to the prioritization and planning of improved water services, resulting in better outcomes for areas that had largely been left out of previous water system expansions [67].

Beyond specific community mobilization efforts, broader mechanisms for gathering public feedback have also been important in ensuring that service providers were effectively meeting residents’ needs. The utilities in both Bangkok and Phnom Penh developed such mechanisms, with feedback in Phnom Penh leading PPWSA to establish easily accessible payment centers in low-income areas [95]. Outside of these two utility-driven contexts, other mechanisms for public feedback included a consumer relations center set up in Abidjan by the regulator (ONEP) and specific rights for civil society organizations to mediate between communities and the municipality in Ahmedabad [71, 75]. As in other locations [116, 118], these public engagement and accountability measures helped to ensure that service providers meet needs on the ground, including in low-income areas.

3.3.3. Service delivery approaches.

Increased metering of piped networks has contributed to substantial reductions in non-revenue water and improvements in service reliability. The literature identifies non-revenue water and reliability concerns, caused by issues such as leaks and illegal connections, as key challenges for piped water systems [1, 8]. The Bangkok and Phnom Penh cases showed that increases in metering, coupled with utilities’ efficiency reforms and transparent reporting of illegal connections, have successfully addressed non-revenue water and reliability concerns. From 1993 (the beginning of Director Chan’s leadership in Phnom Penh) to 2006, PPWSA reduced non-revenue water from 72% to 6% and increased water supply durations from 10 to 24 hours per day, while the city’s piped coverage area rose from 25% to 90% and the total number of connections increased by more than a factor of five [64]. Similarly in Bangkok, the reforms arising from the 1997 financial crisis reduced non-revenue water from 40% to 30%, with water flowing 24 hours a day [8, 59]. In contrast, Ahmedabad has continued to provide intermittent supply, with piped water only available for an average of two hours per day in 2010 [76]. Around the same time, non-revenue water was estimated to be 25–31%, though this metric has been difficult to measure due to a lack of metering [76, 119, 120]. The municipality’s use of taxes to fund operations–as opposed to consumption tariffs–may have lessened the perceived need for meters from a direct financial standpoint [74, 119], potentially also contributing to the city’s intermittency problems due to a limited capacity to detect leaks or illegal connections.

3.3.4. Social, economic, and political context.

A key feature of the social, economic, and political context concerned the sources and methods used to cover the water sector’s capital investments and operational expenses. Consistent with the literature [14, 17, 110], international support often contributed to capital infrastructure development in our cases, while consumption-based tariffs have typically funded operations. Alignment with donor countries’ economic or political priorities have led to strong funding relationships. For example, until the civil wars beginning in 2002, Cote d’Ivoire’s political stability, pragmatic policies toward former colonial powers, and capitalist priorities led to sustained relationships with international organizations and nations such as France [69]. Similarly in Egypt, President Al-Sadat’s Open Door Policy in 1974 led to increased alignment with the United States and Europe and high availability of foreign capital for infrastructure development [60, 100]. In Cambodia, following the Paris Peace Agreement that ended the country’s civil war in 1992, the lifting of trade embargoes made possible international aid to support the country’s reconstruction [121]. Director Chan, whose tenure at PPWSA began in 1993, capitalized on this political and economic climate by working with development agencies and Cambodia’s newly elected government to support the utility’s institutional reforms [8, 24, 121]. Concerning operations, most cases have achieved financial sustainability through tariffs. Phnom Penh saw particular success in raising local tariffs to financially sustainable levels through a gradual, stepwise process that involved educational campaigns, political support, and evidence of improved utility efficiency and performance to promote public acceptance [17]. In Cote d’Ivoire, nationally-set tariffs enabled the distribution of revenues across various national actors to fund operations as well as some level of infrastructure investment and debt servicing [69].

Moving beyond financial viability, political practices with strong democratic elements, particularly geared toward citizen participation in broad local planning processes, supported greater equity in service provision (Fig 4). The participatory budgeting processes applied in Porto Alegre provided a key example of these types of practices. Participatory budgeting was introduced by the local Workers Party, which had a strong commitment to democracy and came to power in 1989. In particular, the party aimed to create an arena for low-income residents to contribute to spending decisions that would address inequities, and this political commitment has been cited as the key driver of the effort’s success [66, 67]. Participants consistently prioritized water and sanitation, and access to these services increased in historically underserved neighborhoods [67]. In Ahmedabad, India’s longstanding tradition of collectivist and movement-based struggles dating back to the country’s independence contributed to the municipality’s leadership and vision in pursuing participatory projects that improved basic services in low-income areas [56, 122]. Finally, Phnom Penh’s utility-driven progress showed the value of politicians, including the city’s governor and the country’s prime minister, approving of the utility’s increased autonomy and supporting the need for increased tariffs, metering, and identification of illegal connections [17].

Similarly, a growing recognition of the complex realities associated with informal areas [36, 42] have supported shifts in public mindsets toward greater rights and levels of services in these locations. Municipal governments in Cairo and Bangkok moved away from classifying these areas as “illegal” and saw the creation of dedicated programs focused on improving services [123, 124]. Bangkok provided a particularly early example of these shifting mindsets in the 1970s, when popular views evolved to see low-income residents as having a right to basic services [58]. In Phnom Penh, the municipal government (supported by UN-Habitat) developed an Urban Poverty Reduction Strategy in 1999 that ended the practice of treating squatters as illegitimate residents and that decentralized some decision-making power to communities [125]. Finally, Ahmedabad has also been a pioneer in this area, ensuring service provision for peripheral low-income areas through holistic slum upgrading programs coupled with official expansions of city boundaries [56, 71, 76, 105, 113, 114].

3.3.5. Environmental and resource context.

Water pollution concerns were a common element contributing to advancements in water supply and (waste)water treatment. In Ahmedabad, pollution of the Sabarmati River led to additional sewage treatment plants [76], while surface water pollution associated with severe flooding in Bangkok led the city to change its water supply and treatment approaches [77]. In Porto Alegre, the presence of blue algae in Guaiba Lake, where waste was discharged, led to the development of an “integrated water cycle vision” covering the sanitation chain from household sanitation infrastructure to discharge of effluent wastewater [82], with the goal of better protecting the city’s water resources.

Beyond water pollution concerns, the occurrence or possibility of broader environmental shocks also spurred efforts toward increased water resilience and security. Bangkok’s overextraction of groundwater, which led to land subsidence that damaged the pipe network, combined with flood events that were made more severe by land subsidence, spurred changes in the city’s water supply approach. In particular, a 1983 cabinet resolution aimed to phase out groundwater use [89, 126]. While the utility did not fully reach the target, less than 0.4% of its water supply came from groundwater by 2001 [8, 126]. This example is consistent with literature noting that natural disasters can highlight weaknesses in existing systems and focus attention on necessary improvements [6].

Cairo was selected as one of our six cases primarily due to its high levels of water stress. The Nile River provides the main water source in an extremely arid climate, and this fact has driven a number of development decisions within the country [62, 127]. Most recently, the Grand Ethiopian Renaissance Dam–under construction since 2011 –is expected to reduce the Nile’s flow into Egypt by 25%, exacerbating concerns regarding the country’s large water demands [127]. As a result, Egypt’s National Water Resources Plan 2037 and National Vision 2030 both included provisions focused on developing new water supplies, advancing water purification technology, managing demand, and increasing wastewater reuse to improve water security [79, 127]. As of 2020, treated wastewater from Cairo has reportedly been used to irrigate timber and non-food crops [127]. While water reuse for agricultural irrigation does not directly contribute to urban service provision, it does advance overall water security in Cairo by lowering demands on Nile water.

4. Discussion

While our findings generally did not contradict prior literature, our analysis added three key contributions:

  1. it addressed several unresolved debates from the prior literature, such as how to effectively monitor service performance in the absence of an independent regulator, how to ensure progress achieved through individual champions is sustainable, how certain institutional arrangements can promote integrated upgrades for low-income areas, strategies for removing land tenure requirements for piped connections, and the importance of explicit pro-poor measures and mandates as compared to general constitutional rights to water (see Sections 4.1 and 4.2 for more detail, as well as Table B in S1 Text);
  2. it consolidated prior knowledge as well as new insights derived from the six study cities into a unified list of key characteristics supporting inclusive improvements in water service provision (Fig 4); and
  3. it defined a typology to categorize success pathways according to the institution driving reforms (i.e., utility/service provider, regulator, municipality/local government; Fig 3), which suggests that multiple potential entry points exist to catalyze progress.

Generally, our six cases showed that a variety of factors and approaches may effectively support safe and inclusive services, with the most appropriate strategy depending on existing institutional arrangements, infrastructure, and the surrounding social, economic, political, and environmental context.

4.1. Overarching lessons from the three types of progress

Overall, the three types of progress identified in our six cases suggest that improvements in urban drinking water access may occur in different ways, depending on existing institutional arrangements and contextual factors, and they offer multiple entry points (e.g., service providers, regulators, governments) through which implementing organizations may promote and support advances. Additionally, they illuminate three lessons that contribute toward addressing unresolved conversations within the literature (Table B in S1 Text), both within our six cases and beyond. First, performance monitoring can take multiple forms and does not necessarily require an independent regulator. The literature commonly recommends approaches involving independent regulators as being most effective and transparent [3, 5, 8, 13, 17, 115, 128, 129]. We observed this type of model in Abidjan and Cairo, where independent regulators tracked performance indicators and produced or reviewed annual reports covering multiple locations or utilities throughout the country [50, 63]. Similar approaches also exist elsewhere in sub-Saharan Africa, where stakeholders have focused on developing strong regulatory environments for water and sanitation [40]. However, other types of performance monitoring, especially those characterized by proactive utilities or municipalities with internal oversight bodies, can also be effective under the right conditions. In particular, the oversight body should have a degree of separation from operational activities to encourage honest reporting and include members representing various stakeholder interests [8, 59, 64].

Second, champions can drive sustainable institutional reforms. While the efforts of passionate individuals can move the needle on reforms and can be particularly important in weak institutional or regulatory environments [130], existing literature has noted that champion-led progress may not be sustainable if key individuals retire or change assignments [6, 14, 17, 24, 115]. For example, the reassignment of a proactive ministry secretary who had effectively promoted communication in Kenya led to concern among sector actors that progress would stall and priorities would change [115]. However, our two cases in which champions played a prominent role in utility-driven progress–PPWSA Director Ek Sonn Chan in Phnom Penh and MWA Governor Chuanpit Dhamasiri in Bangkok–showed that the improved performance levels achieved through champion-led utility improvements can be sustainable beyond the individual’s tenure [17, 59]. These cases provided examples of institutional reforms, staff incentives, and accountability mechanisms that created a lasting culture of transparency and efficiency. Some specific examples included increasing staff salaries, creating customer databases and automated billing systems, and establishing incentives for staff to report illegal connections [17]–measures which may translate well to low-performing contexts where utilities play a central role in the sector. Director Chan also reportedly took additional steps to prepare the utility for his retirement by training future management staff and promoting the strong institutional culture he created [81].

Finally, municipalities that directly provide services, such as in Ahmedabad, may integrate water provision with other services to holistically upgrade low-income areas. Previous literature has noted that upgrading multiple services simultaneously has often generated advancements in water coverage and service levels within low-income areas, for example by installing piped networks when improving road infrastructure [1, 5, 7, 13, 17], but less information exists regarding the institutional arrangements that can effectively support integrated strategies. The institutional arrangement demonstrated by Ahmedabad offers a notable example of how to achieve such upgrades. In locations where the municipality is directly responsible for delivering multiple services–and especially when a clear mandate exists to serve the poor–it can reduce the need for high levels of coordination across a number of institutional actors that may have different mandates and incentives. Ahmedabad also showed, however, that coordination and partnership with NGOs can enhance accountability and encourage public officials to commit to service improvements [107].

4.2. High-performing service providers and pro-poor strategies across different types of progress

Along with these lessons associated with different types of progress, the 12 characteristics of the enabling environment we identified across our six cases highlighted two broad themes. First, a generally well-functioning water sector is often a prerequisite for inclusive, pro-poor service provision. If utilities, regulators, or municipalities are not operating efficiently and performing baseline functions adequately, it is unlikely that they will have the capacity to push for improvements among the poor, who are often the hardest to reach. In particular, elements such as clear performance indicators, institutional reforms for greater efficiency and transparency, customer feedback mechanisms, increased metering to improve reliability, financially sustainable strategies to fund operations and infrastructure investments, and the use of crises to spur progress contributed to the overall success of our cases. Generally, these elements align with existing literature, and international funding institutions often promote many of them (apart from crises) when providing financial assistance [64, 65]. Similar measures could likely also contribute to progress in other, lower-performing settings.

Second, realizing more inclusive water services often requires the application of explicitly pro-poor policies and strategies that are contextually appropriate. Effectively serving low-income residents may necessitate dedicated measures that are distinct from conventional approaches used in wealthier parts of the city. These measures might include connection and consumption subsidies, the removal of land tenure requirements for piped connections, community mobilization that enables low-income residents to participate in decision-making and service provision, and democratic practices that support efforts to upgrade low-income areas and validate their residents’ rights to services. However, in our cases, explicit constitutional rights to water were often absent, and when these rights did exist, they tended to be less instrumental for improving equity than specific pro-poor mechanisms. This point speaks directly to one of the unresolved debates identified from existing literature (see Tables A and B in S1 Text for additional insights from the case study analysis that relate to elements identified in the literature review).

4.3. Limitations

Perhaps the most important limitation of this work is the small (though diverse) number of study cities. Our focus on successful cases limited opportunities to identify direct counterfactuals characterized by low performance. Accordingly, while this study provides an important step in identifying factors that may contribute to successful provision of urban drinking water, it did not directly test whether the characteristics we identified were necessary or sufficient for promoting success. Future research using fuzzy-set Qualitative Comparative Analysis (fsQCA) [131] and a larger sample size should examine the relative importance of the enabling factors identified here.

Additionally, our cases may not have provided insight into the full range of characteristics or types of progress that can drive improvements in water service provision across all settings [132]. Our case selection process explicitly aimed to capture a diversity of contexts, but the process also showed that we could have included a number of other cities, which may have emphasized different elements of the enabling environment. We limited the number of selected cases to six, which we felt enabled us to explore the complexities of each context with a high level of detail while also examining multiple settings. However, each of our cases exhibited some degree of path dependence [51], in that institutional arrangements and service characteristics were often contingent upon a city’s unique history. Accordingly, future study of additional cities with different historical trajectories may uncover new ingredients for success at work in other contexts.

Furthermore, we focused primarily on improvements in piped water access, but successful service arrangements that include non-piped provision may also exist. The literature has highlighted hybrid modes of service delivery, in which various public and private actors provide piped and non-piped services, and scenarios where utilities have been experimenting with approaches drawn from informal providers to expand services in low-income areas [6, 16]. We found some similar examples of hybrid provision in our cases, such as delegated management models in Bangkok and water resellers in Abidjan, but other settings may provide further insight on how utilities and municipalities can work together with private operators to effectively serve low-income residents.

It is also worth noting that the eligibility screening phase of our case selection process focused on piped water access and did not directly incorporate other important elements of successful service provision such as quality, reliability, and affordability, because we were unable to find data on these indicators across all candidates. Generally, piped water service is viewed as the gold standard, providing the highest quality water at the greatest level of convenience [1, 18]. Also, the use of open-ended expert interviews to identify successful cities prior to eligibility screening did provide a qualitative understanding of performance beyond piped coverage. However, not directly including these other elements in the process may have affected our final selections, some of which proved to be less successful with respect to certain indicators. For example, while Ahmedabad has promoted equitable access and inclusion of low-income residents, piped water services across the city were only available for an average of two hours per day in 2010 (Table J in S1 Text).

Finally, the limited number of interviews, especially when we were only able to conduct a single interview per case, may have influenced or biased our understanding of that case. We aimed to identify interviewees from institutions with a broad perspective on each context, and we followed up with additional individuals in specific roles when possible. However, it is possible for institutional or personal biases and blind spots to affect perceptions of key drivers and actors. Conducting extensive literature reviews for each case and framing the interviews as supplemental to the literature helped prepare us to identify and adjust for any potential biases. However, we may still have missed certain influences arising from interviews.

4.4. Possibilities for future research into pro-poor water service provision

As stated previously, future research that directly follows from this study could apply fsQCA [131] to evaluate the importance and relationships of the characteristics we identified across a larger number of successful and unsuccessful cases. This type of work could offer insight into the degree to which these characteristics hold true in a broader array of contexts, and how they may work together to contribute to improvements in urban water services. There may also be opportunities to integrate or conduct additional analyses of new, innovative regulatory and service provision models currently being implemented in LMICs, particularly related to citywide inclusive sanitation and fecal sludge management [5, 110, 116, 118].

Furthermore, a number of additional questions arose from the cases related to the development or advancement of specific pro-poor measures. First, the electricity sector may offer lessons on how to lift or bypass land tenure requirements for service connections. Ahmedabad and Cairo both offered clear examples of cases where low-income households with unclear land tenure status have acquired electricity connections ahead of piped water, as they used electricity bills to show proof of residency when applying for water connections [76, 103]. Future research focusing on how the electricity sector has removed land tenure requirements may be useful for the water sector in moving beyond this critical barrier to piped access.

Second, better characterizing the incentives that can effectively formalize small-scale providers is important, particularly when piped networks cannot reach certain segments of a city’s population. In Abidjan, the utility began attempting to license water resellers in the early 1980s, but these efforts were largely ineffective due to misaligned or insufficient incentives. Estimates from the late 1990s showed the number of informal resellers to be ten times larger than those with licenses [108, 133]. In such instances, some form of non-piped provision may be necessary, at least in the short term. Finding ways to successfully formalize these actors–into cooperatives, for example–may provide better opportunities for monitoring to ensure safe and affordable services, although literature has noted that pricing control may remain politicized in certain contexts [6].

Third, the use of a property tax surcharge to fund water services in Ahmedabad was an interesting alternative to the more common use of consumption-based tariffs [74]. However, it was unclear from our cases how successful this approach would be in LMICs when the municipality is not directly providing services, as this scenario would likely require high levels of coordination to efficiently and appropriately allocate tax revenues to the service provider. Further research on this topic could be beneficial in increasing the range of options available for achieving financially sustainable operations. Another interesting financial strategy from Ahmedabad involved the use of municipal bonds to enable infrastructure investments [71]. Studying the effectiveness and applicability of municipal bond markets to provide funding for capital improvements in lower-income contexts may also be worthwhile. This area of inquiry may be particularly timely, given recent findings from sub-Saharan Africa related to how constitutional and regulatory constraints can limit sub-national governments’ use of municipal bonds [134].

Finally, the adverse impact of unplanned urban expansion on citywide water service provision was clear across our six cases, but we found limited information on cities taking proactive measures towards reducing future unplanned expansion. Ahmedabad was a notable exception: while the city’s administrative boundaries increased periodically to encompass surrounding low-income areas, the city’s Urban Development Authority also established policies to reduce urban sprawl. It is worth noting that, although the city has successfully promoted equitable access and inclusion of low-income residents, it also provided a citywide average of only two hours of water service per day [56, 114]. Generally, however, the water sector literature on which we focused did not commonly engage with literature from the land use planning sector. Further research may be beneficial in identifying forward-thinking land use strategies to proactively address issues of service provision in unplanned areas.

5. Conclusion

Achieving equitable access to safe water services remains a key challenge in many urban areas of low- and middle-income countries. Our findings from six cases, each of which has made substantial progress toward this goal, demonstrate that multiple pathways toward improvement exist, and the relative importance of the various approaches, measures, and characteristics contributing to the enabling environment for urban water provision will vary from place to place. However, key elements identified in this study reflect how different sector players, including utilities, regulators, and local governments, can generate sustainable progress across various contexts, and how interventions in lower-performing cities may target each of these actors as entry points for promoting an effective enabling environment. In particular, utility-focused programming can concentrate on encouraging champions to institutionalize any strategies they use to improve service delivery and efficiency by defining clear policies and reforms, promoting clear key performance indicators for regular monitoring by external or internal bodies, and building credibility through public engagement and performance improvements to pave the way for necessary tariff increases. Similarly, programming to support regulators can emphasize regulatory frameworks defining clear roles and responsibilities within the sector, as well as the development of performance indicators specific to low-income areas. Finally, support for local governments can focus on developing or enforcing clear policy mandates for service provision in low-income areas, and on establishing strong financial management systems to promote infrastructure investments. Overall, these strategies and lessons, derived from various settings and institutional landscapes, can offer insight for decision-makers and underpin efforts in the numerous cities continuing to work toward universal access to safe water.


The authors would like to thank Irene Atieno, Faith Chepngeno, and Edinah Samuel for their assistance in identifying relevant literature, developing narratives, and generating graphics for the case studies. We are also grateful to the experts and key informants we interviewed to shortlist cities and explore individual cases. Finally, we thank Ryan Mahoney, Jesse Shapiro, Daniel Smith, Rachel Peletz, and our consortium partners in the Urban Resilience by Building and Applying New Evidence in Water, Sanitation, and Hygiene (URBAN WASH) project for their help at various stages of study design and manuscript preparation.


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