Safely Managed Sanitation for All Means Fecal Sludge Management

Jan 27, 2017 - ABSTRACT: Although global access to sanitation is increasing, safe ... current need for fecal sludge management (FSM) in LMICs by regio...
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Safely managed sanitation for all means fecal sludge management for at least 1.8 billion people in low and middle income countries David M. Berendes, Trent A. Sumner, and Joe M. Brown Environ. Sci. Technol., Just Accepted Manuscript • DOI: 10.1021/acs.est.6b06019 • Publication Date (Web): 27 Jan 2017 Downloaded from http://pubs.acs.org on February 7, 2017

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Safely managed sanitation for all means fecal sludge management for at least 1.8 billion

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people in low and middle income countries

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David M. Berendes*1, Trent A. Sumner1, Joe M. Brown1

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1

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Georgia, USA; *corresponding author (email: [email protected]; address: 311 Ferst

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Dr. #3368, Atlanta, GA, 30332; phone: 404-894-3317; fax: 404-894-2278)

School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta,

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Abstract

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Although global access to sanitation is increasing, safe management of fecal waste is a rapidly

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growing challenge in low- and middle-income countries (LMICs). The goal of this study was to

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evaluate the current need for fecal sludge management (FSM) in LMICs by region, urban/rural

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status, and wealth. Recent Demographic and Health Survey data from 58 countries (847,685

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surveys) were used to classify households by sanitation facility (facilities needing FSM, sewered

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facilities, ecological sanitation/other, or no facilities). Onsite piped water infrastructure was

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quantified to approximate need for wastewater management and downstream treatment. Over all

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surveyed nations, 63% of households used facilities requiring FSM, totaling approximately 1.8

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billion people. Rural areas had similar proportions of toilets requiring FSM as urban areas. FSM

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needs scaled inversely with wealth: in the poorest quintile, households’ sanitation facilities were

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almost 170 times more likely to require FSM (vs. sewerage) than in the richest quintile. About

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one out of five households needing FSM had onsite piped water infrastructure, indicating

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domestic or reticulated wastewater infrastructure may be required if lacking for safe management

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of aqueous waste streams. FSM strategies must be included in future sanitation investment to

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achieve safe management of fecal wastes and protect public health.

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Introduction

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While progress toward meeting the Millennium Development Goal (MDG) target for sanitation

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fell short in 2015—an estimated 2.4 billion people still lack access to improved sanitation1—

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significant expansion in global coverage has been achieved in the MDG era, and investment

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continues to reduce open defecation and expand access to safer sanitation facilities. Sustainable

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Development Goal (SDG) 6 goes further,2 explicitly recognizing the normative goal of “safely

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managed” sanitation in addition to coverage, highlighting the importance of safe excreta disposal

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to reduce health risks. This shift is also reflected in refinements to the “sanitation ladder”

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approach adopted by the Joint Monitoring Program (JMP), explicitly focusing on the safe

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management of fecal wastes to reduce downstream exposures.1

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Wastewater management—the removal of fecal wastes through water-based transport to

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downstream treatment and disposal (e.g. piped networks like conventional sewerage)—has been

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practiced as the normative standard for management of fecal waste since the mid-1800’s in urban

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areas, where population density creates economies of scale.3 Fecal sludge management (FSM)—

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the on-site management of fecal biosolids with generally lower water content—is a challenge

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with new visibility in the urban sanitation sector in low and middle-income countries (LMICs).4

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The advent of fecal waste flow diagrams and sanitation mapping exercises have revealed the

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global predominance of on-site sanitation (dry or pour-flush latrines), even in settings where high

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population density might justify reticulated sewerage.5,6 Many sanitation facilities available to

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both the urban and rural poor require FSM to adequately sequester fecal wastes: a delayed, rather

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than immediate, problem. The apparent global need for FSM services may be partly attributable

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to the metrics-driven focus on expansion of toilets to increase coverage and reduce open

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defecation, justifiably apriority in meeting immediate sanitation needs. More latrines, however,

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leads to concentration of wastes that must be safely managed to protect public health. FSM has a

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tendency to be forgotten during and after infrastructure is built.7,8

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Many households in LMICs have sanitation facilities requiring FSM services7 Despite

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FSM’s central importance to the functionality, impact, and sustainability of global sanitation

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infrastructure, no estimate of the worldwide need for FSM services is available. An accounting

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of how many households require FSM is an essential step in the effort to ensure sanitation

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infrastructure and services deliver the greatest possible health impact under the SDGs. Such

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estimates are also valuable for advocacy, targeting FSM programs, and stimulating interest in

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developing better FSM technologies and services to meet growing needs as sanitation coverage

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expands.

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This study examined the worldwide prevalence of households using sanitation facilities

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requiring FSM based on recent Demographic and Health Survey (DHS) data from 58 LMICs.

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We assessed the types of sanitation facilities reported to be used by households by World Health

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Organization (WHO) region, urban/rural status, and wealth quintile to quantify the current

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prevalence of sanitation facilities requiring FSM to function safely and to understand how this

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prevalence varies across key population segments. We also estimated the proportion of facilities

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reportedly used by households connected to water supplies to inform future demand for

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wastewater management. This research will contribute to quantifying inequalities in the need for

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FSM and wastewater management in LMICs worldwide, an explicit focus of the SDGs in

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addressing sanitation needs for the poorest of the poor.2

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Methods

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Data sources

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Data for this study were extracted for analysis from the Demographic and Health Survey (DHS)

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program from Phase 5 (2003-2008), 6 (2008-2013), and 7 (current, 2013-2018: the most recent

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survey was from 2015) surveys. DHS surveys are country-specific and if a country had more

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than one survey within the Phase 5-7 period, only the most recent survey data were analyzed.

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DHS methodology generally involves two-stage sampling: selection of enumeration

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areas/clusters followed by selection of households.9 Household questionnaires ask about

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numerous topics, including water and sanitation. Questions about the kind of toilet facility used

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by the members of the household and the main source of drinking water for the household were

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the focus of this analysis. Further, information about urban or rural location of the household and

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wealth were obtained from each survey. Wealth indices were country-specific and based on

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household assets and utilities, which were weighted by the DHS program using principal

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components analysis. These index scores were then grouped into country-specific wealth

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quintiles based on household population figures from the survey.10

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Classification of DHS Sanitation and Drinking Water Source Questions

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DHS questions about the sanitation facility (DHS question 109 in Phase 7 survey11) and type of

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drinking water source (DHS question 101 in Phase 7 survey11) were used to classify households’

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need for fecal sludge management (FSM) or wastewater management. First, households’

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responses to the type of sanitation facility usually used were classified into four categories: 1)

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use of facilities connected to sewerage or sewers—any response listing connection to sewered or

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piped system (“Sewered”); 2) use of facilities that were composting toilets, associated with

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composting facilities, “other”, or no response (“Other/EcoSan”); 3) no use of facilities (“No

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facility”); and 4) use of facilities that retain waste onsite (latrines connected to septic tanks and

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subsurface discharge or pits) or discharge waste onsite (latrines with surface discharge) and

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therefore must be managed onsite (“FSM needed”). Second, households’ responses to reported

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drinking water source were grouped into 4 categories based on location and type of infrastructure

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associated with the source: 1) drinking water sources that were piped into the household or plot

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(“On-premises piped connections ”, though the source may not have been onsite); 2) sources that

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were onsite, but not piped, or were present at a neighbor’s house (“Other on-

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premises/neighbor”); 3) sources that were not listed as onsite or at a neighbor’s house (“Not on-

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premises”); and 4) other/no response (“Other”). Responses from both of these questions allowed

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broad categorization of households by potential need for wastewater vs. FSM based on the type

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of sanitation facility and piped water infrastructure present. On-premises water supply, in

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combination with sanitation facilities, was used to indicate potential current or future demand for

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pour-flush or flush latrines using water to convey waste, and therefore higher wastewater

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volumes and need for access to septic systems with safe discharge (low population density) or

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sewerage (high population density).

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The proportions of households per country in each category were calculated using

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complex survey weighting to account for the two-stage cluster survey techniques used in the

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DHS.9,12 Households not responding to these questions were included in the denominator to

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ensure accurate survey weighting and population estimates (see below). Households were further

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divided by urban/rural status and wealth quintile. Use of sanitation facilities was quantified 1)

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among all households, (including those with no access to sanitation); and 2) among only those

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households reporting using sanitation facilities (to better describe FSM needs among those with

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current access to a sanitation facility).

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Population estimation

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The most-recent (2016) country-level population estimates from the Central Intelligence

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Agency (CIA) Factbook13 were multiplied by the weighted proportions of households in each

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category to estimate the total population in each category.

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Analysis Data were analyzed from 847,685 surveys from 58 countries across all six World Health

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Organization (WHO) regions: 33 countries in Africa, 7 in Latin America and the Caribbean

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(“LAC”), 6 each in Europe and Southeast Asia, and 3 each in the Eastern Mediterranean (“E.

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Med.”) and Western Pacific (Table 1). The total estimated population across the 58 countries in

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the analysis was 3,205,819,618, representing 44% of the global population and 54% of the

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population residing in LMICs as defined by the United Nations.14 All analyses were conducted in

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R version 3.2.1 using base packages, as well as the “lme4” package for mixed-effects logistic

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regression and the “survey” package for complex survey weighting.15–18 Mixed-effects logistic

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regression models were used to quantify the magnitude of associations between a) drinking water

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location, b) urban/rural status, and c) wealth quintile; and the reported use of a sanitation facility

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that required FSM to function (compared to those connected to sewerage). Random effects for

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country of the survey, as well as enumerations areas within each country, were included in the

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model.

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Results

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FSM requirements among surveyed nations

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The average prevalence and total population of households that reported using different

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categories of sanitation facilities (connected to sewerage vs. those in need of FSM vs. no facility)

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were calculated by country. Prevalence estimates were then averaged by WHO region and across

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all countries surveyed, with estimated populations summed (Table 1). Over all countries

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surveyed, an average of 63% of all households reported using sanitation facilities in need of

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FSM, summing to almost 1.8 billion people out of the 3.2 billion people currently living in the

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included countries (56%). The population-level need for FSM was greatest in Africa (mean of

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65% of households, summing to 577 million people) and Southeast Asia (mean of 61% of

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households, summing to 816 million people), though the Western Pacific had the highest mean

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proportion of households reporting using facilities requiring FSM (74%).

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To assess the need for FSM among households with current access to a sanitation facility,

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we conducted a separate analysis of the prevalence and population of households that reported

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using facilities in need of FSM among only those that reported using a sanitation facility.

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Overall, 81% reported using sanitation facilities needing FSM, with over half of households

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reported using sanitation facilities that needed FSM in all regions (data not shown). The largest

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average figures were in the Western Pacific (94%), Africa (90%), and Southeast Asia (81%),

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followed by LAC (63%), E. Med. (56%), and Europe (60%). Notably, almost 22% (more than 1

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billion people) of households in surveyed nations did not use a facility currently.

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Overall, an average of about one-quarter of households (26%) reported using on-premises

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piped connections to water sources (693 million people). Few households (< 2% on average)

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reported using other on-premises or a neighbor’s water sources, while most (70% on average,

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summing to over 2.3 billion) reported using an off-premises drinking water source.

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FSM needs in urban and rural areas in surveyed countries

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The average proportions of households reporting using sanitation facilities needing FSM

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were similar in urban (66%) and rural (65%) areas, though the urban population-level need was

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lower (735 million) when compared with the rural areas (1 billion, Table 2). Among households

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that did not report using sanitation facilities needing FSM, the majority (79%, 248 million) in

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urban areas reported using sewered facilities, while the majority (89%, 959 million) in rural areas

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did not report using a facility. A larger average proportion reported using sanitation facilities

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needing FSM in urban areas, compared with rural areas, in the African region (78% vs. 60%) and

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W. Pacific region (80% vs. 73%). However, the size of the population that reported using

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facilities in need of FSM was generally higher in rural areas than in urban areas. Over 2.5 times

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more people reported using facilities in need of FSM compared with sewerage in urban areas

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(735 million vs. 285 million), while over 30 times more people reported using facilities in need

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of FSM compared with sewerage in rural areas (1 billion vs. 32 million).

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Among only households that reported using sanitation facilities, an average of 72% in

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urban areas and 91% in rural areas reportedly used facilities that need FSM to function (data not

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shown). This proportion was more variable by region in urban areas (range: 30 – 86%) compared

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with rural areas (range: 76 – 98%). The African (86%), W. Pacific (83%) and Southeast Asian

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(67%) regions had the largest urban proportions. In contrast, rural areas of all regions, with the

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exception of LAC, had at least 88% of households using facilities needing FSM.

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FSM needs by wealth quintile in surveyed countries

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While the need for FSM appeared to be unrelated to wealth quintile across all households,

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among households that reported using sanitation facilities (thus excluding households without

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access to sanitation facilities, the need for FSM scaled with poverty (Table 3). For example, in

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the richest households, an average of 64%—representing 66% of households that reported using

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sanitation facilities (data not shown)—reported using sanitation facilities needing FSM services.

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In contrast, in the poorest households, 50%—representing 92% of households that reported using

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sanitation facilities—reported using sanitation facilities needing FSM services. Almost 47% of

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the poorest households did not report using a sanitation facility.

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By population, about 2.5 times more people reportedly used facilities needing FSM than

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sewerage in the richest quintile (457 million vs. 177 million), while almost 75 times more people

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reportedly used facilities needing FSM than sewerage in the poorest quintile (209 million vs. 2.8

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million). Though the proportion of households that reported using facilities needing FSM in each

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wealth quintile was generally higher in rural areas than in urban areas, the trend of increasing

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need for FSM from richest to poorest households among households reporting using sanitation

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facilities was consistent between rural and urban areas (data not shown).

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FSM needs and wastewater management potential by region among surveyed nations

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To estimate the potential for wastewater management (in contrast to FSM), reported use

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of “on-premises piped connections” for drinking water (from measurement of the location of a

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household’s reported drinking water source) was used as an indicator of potential preference for

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or possibility of flush toilets (and subsequent need for additional reticulated or domestic

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wastewater infrastructure such as sewerage or subsurface discharge of septic effluent, Table 4).

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Overall, an average of 69% of households with on-premises, piped connections to drinking water

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sources reported using sanitation facilities in need of FSM to function, representing over 381

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million people (about 22% of the almost 1.8 billion in need of FSM). These population figures

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were highest in Southeast Asia (191 million), Africa (almost 76 million), and the Western Pacific

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(43 million). In the Western Pacific, 93% of households with onsite, piped drinking water

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reported using sanitation facilities in need of FSM to function. Of note, almost 100 million

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people reported using sewered sanitation facilities, but reported having a drinking water source

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that was not on the premises.

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Households’ wastewater management and FSM needs were further divided by urban/rural

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areas and wealth (Table 5). About two-thirds (259 million) of the 384 million who reported using

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both on-premises piped connections for drinking water and sanitation facilities in need of FSM

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were in urban areas. However, an average of 78% of households in rural areas with on-premises

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piped connections for drinking water reported used sanitation facilities in need of FSM. Overall,

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when moving down in wealth quintile in each water category, the proportion of households that

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reported using sewered facilities decreased and the proportion reportedly not using a facility

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increased, similar to previous observations.

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When examining only households that reported using sanitation facilities by wealth

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quintile and drinking water location, both drinking water location and management of the

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sanitation facility varied with wealth. Among the richest, 128 million (21%) reported using both

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on-premises piped connections for drinking water and sewered facilities, another 187 million

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(31%) reported using on-premises piped connections but used sanitation facilities in need of

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FSM (as well as 48 million reportedly using sewered facilities without on-premises piped

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connections), and 246 million (40%) did not report on-premises piped connections and needed

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FSM for their sanitation facilities. However, among the poorest, there was very little reported use

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of 1) both on-premises piped connections for drinking water and sewered facilities (1 million,

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0.5%); or 2) on-premises piped connections with sanitation facilities in need of FSM (15 million,

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8%). Instead, the majority (180 million, 91%) lacked on-premises piped connections and needed

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FSM for their sanitation facilities.

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Multivariate modeling of drinking water location, household location, and wealth on FSM need

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within surveyed nations

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To understand the magnitude of associations between drinking water location, household

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location (urban/rural status), wealth, and the need for FSM, mixed-effects logistic regression was

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used to model sanitation facilities needing FSM relative to those that were sewered among

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households reporting using sanitation facilities. Nested random effects were included for the

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country and sub-country enumeration areas of each survey. Estimates of odds of needing FSM

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(vs. having sewerage) are presented with 95% confidence intervals for the single, multivariate

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model in Table 6. Households that reported using on-premises piped connections for drinking

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water were half as likely to report using a sanitation facility in need of FSM compared to those

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with water sources that were not onsite. Households in urban areas were 90% less likely to report

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using sanitation facilities needing FSM compared with those in rural areas. Finally, the odds of

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reporting using a sanitation facility needing FSM increased exponentially with decreasing wealth

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quintile (increasing relative levels of poverty). Compared with the richest households, those in

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the next lower quintile were 2.7 times more likely to report using a sanitation facility in need of

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FSM, while those in the poorest wealth quintile were almost 170 times more likely.

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Discussion The goal of this study was to estimate the current global use of sanitation facilities

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requiring fecal sludge management (FSM) to continue to function, as well as divided by region,

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urban/rural setting, wealth, and presence or absence of on-premises piped connections for

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drinking water (an indicator of waste stream type and potential mobility of fecal waste). Among

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the 58 countries included in this analysis, almost 1.8 billion people (56%) reported using

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sanitation facilities requiring FSM to function properly, with the highest needs in rural areas.

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Among households reporting using sanitation facilities, the poorest were also most likely to use

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facilities in need of FSM, indicating an under-recognized disparity (beyond the 47% in this

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quintile without access to sanitation facilities) that places additional burden on poor households

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seeking to safely manage fecal waste. Discrepancies between the prevalence of on-premises

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piped connections for drinking water and that of sewered sanitation indicate opportunities for

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potential wastewater infrastructure expansion, distinct from FSM as it is usually understood

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(manual or mechanical extraction, transport, and disposal of latrine waste biosolids).

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Although previous estimates of improved sanitation categories exist1, this study is the first

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to quantify the magnitude of the population using sanitation facilities in need of onsite FSM at a

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global scale and to evaluate these needs by wealth equality and urban/rural status, both important

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covariates when informing global, national, and local policy targets and service delivery

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models.19 Further, use of on-premises piped drinking water infrastructure as a proxy for potential

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wastewater management, in lieu of FSM, recognizes that fecal waste management strategies

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depend on the waste stream characteristics, which may change given that rapid expansion of on-

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premises water service may increase wastewater volumes faster than FSM service delivery can

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adapt. The evidence in this manuscript improves the resolution of recent global estimates of

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improved sanitation coverage by the JMP, WHO, and UNICEF1 and geographic inequalities in

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access to improved facilities20—both of which have not quantified FSM and sewerage needs

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separately—in preparation for monitoring the SDGs.2,21

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Within the 58 countries with recent DHS data (2003 – 2015), almost 1.8 billion people

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reported using sanitation facilities that require FSM—representing over 80% of the sanitation

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facilities in LMICs. Though likely an underestimate of the true population-level need worldwide

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due to countries excluded from this analysis, the prevalence of FSM needs vs. sewered sanitation

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facilities underscores the discrepancy in expenses faced by non-governmental organizations,

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local governments, and communities between these sanitation technologies. Many reasons,

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including the almost 40-fold higher initial costs of sewerage, previous emphasis on coverage of

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sanitation facilities, the lack of immediate need for FSM associated with installing sanitation

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infrastructure, and the unsuitability of water-based sewerage systems in certain contexts,

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contribute to sanitation facilities that contain waste onsite being much more prevalent than those

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connected to sewerage worldwide.22–24,6 While onsite containment may safely separate fecal

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waste from human contact immediately after being built, the sustained functionality and usability

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of these facilities depends on management of the sludge: a large logistical and time burden for

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users.22,25 Access, availability, cost, and reliability of FSM emptying services are highly variable

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worldwide, depending on a range of locally specific factors.24,26–29 In contrast to areas already

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piped for sewerage, areas with facilities in need of FSM incur logistical, financial, and

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governmental challenges.6,30,31 Recent studies in large cities of LMICs have indicated that

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governmental organization of FSM is generally poor, making sustained, reliable FSM

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difficult.6,32 With the renewed focus on safe management of fecal sludge along the entire

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sanitation chain in the SDGs, local governments must begin to include longer-term

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considerations of the management of fecal sludge with existing demands for growth of sanitation

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coverage.1,2

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The need for FSM is not restricted to urban areas, where much of the research has been

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focused, but instead is just as prevalent in rural populations.5,6,33 In contrast to the division

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between sewered and unsewered facilities in urban areas, households in rural areas lacked

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sewerage (likely due to infrastructural constraints in connecting households) and thus only

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reported using unsewered facilities, if they reported using a facility at all.23 Despite rural areas

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having more space to dig new pits than urban areas, they face other FSM needs in the form of

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poorer availability of knowledge, training, and resources sufficient for the user to construct a

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new collection area (i.e. dig a new pit), safely cover the old pit, and move the superstructure.29

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Further, in many rural areas of the world, including India, water-based sanitation is a cultural

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necessity, which therefore requires homes to have septic tanks or other onsite collection tanks,

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increases the volume of sludge in the tanks, and necessitates conventional emptying similar to

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urban areas.34,35 Thus, there is a need to provide for the technical aspects and logistics of facility

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maintenance—either through separate services or in trainings to the user themselves—as part of

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sanitation facility construction in rural areas.36

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The costs of FSM needs are unequally distributed across the wealth spectrum due to

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geographic inequities in infrastructure and differences in the financing and payment structures

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between sewerage and FSM. Areas with sewerage are generally more expensive to live in, yet

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have the benefit of wastewater management included in the cost or otherwise borne, in large part,

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by the utility.22,29,37 In contrast, financial structures for FSM pass the majority of costs on to the

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users themselves—up to 84% of the annual operating costs compared to 6% for sewered systems

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in previous literature from Dakar, Senegal.22 These costs, by themselves, constitute a large

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portion (almost 5%) of household income in the poorest neighborhoods and often are borne in

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the form of one-time payments, rather than monthly installments.22,38 These financial concerns—

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with the logistical burden associated with unreliable service—may force the poorest users to

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either empty the waste themselves or abandon regular management of their sanitation facilities,

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contaminating the local environment with fecal pathogens and increasing subsequent health

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risks.22,25,39 In addition to their own fecal sludge, the fecal sludge of others further ‘upstream’

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may impact the exposure of low-income households, for example in urban informal settlements,

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with annual flooding, exacerbating health risks.40–43

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A limitation of this study is that the need for FSM was assessed based on the standard DHS

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sanitation metric, a self-reported measure that largely focuses on where defecation occurs, rather

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than the final fate of the household’s fecal sludge, in the most recent DHS data available for each

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country. There is a need to develop more comprehensive, rapid, feasible, and potentially risk-

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based assessments of sanitation facilities and FSM to measure safe containment along the entire

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sanitation chain.44

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Further, these data give no indication of the composition of fecal sludge biosolids, current

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availability of FSM services, functionality of sewerage, or the final treatment of the fecal sludge

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in either case, limiting conclusions about the overall safety of the sanitation system present or the

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potential for unmet demand for FSM services. While on-premises piped connections were used

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to estimate potential need for strategies addressing more aqueous wastewater streams, the finding

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that 100 million people used sewered sanitation yet lacked on-premises water connections

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suggests a need for further investigation. Also, it is important to note that fecal waste transported

334

by sewerage may remain untreated in its final fate in many cases, thus sewerage – like other

335

FSM strategies - does not guarantee safe sanitation that precludes downstream human

336

exposure.45 Estimates of service provision from a study of 12 cities throughout four of the six

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WHO regions suggest that a majority of fecal waste in onsite systems is not safely managed (61-

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72% in Africa, 62-68% in LAC, 100% in SE Asia, and 5-100% in W. Pacific, the region with the

339

most variation) and in only 1/12 cities were 100% of sewered systems considered safely

340

managed.6 These data represent selected urban areas and thus there is a need for more active

341

research in quantifying current levels of service provision, including in rural areas.

342

While the construction and maintenance costs of sanitation facilities in need of FSM may

343

be lower for the implementer and FSM systems may be more sustainable than water-based

344

sewerage in the long term, their costs need to be included in the sanitation costs associated with

345

achieving the SDGs.22 The need for FSM is growing, both with the future expansion of sanitation

346

coverage to the more than 1 billion people in surveyed nations without a facility and with the

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filling of pits and septic tanks of the almost 1.8 billion people currently served by sanitation

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facilities in need of FSM. Further, increasing coverage of piped water infrastructure supplying

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greater volumes of water to households will likely result in higher prevalence of water-based

350

flush toilet use. Local water provision can therefore change the nature of fecal waste streams,

351

resulting in greater volumes of more mobile waste requiring wastewater conveyance and

352

treatment. More aqueous waste may change technology choice and drive sanitation infrastructure

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development. Given the interconnections between water and sanitation infrastructure expansion,

354

a systems approach to ensure safe management of fecal waste may be helpful to sustain both

355

human and environmental health.46

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The current need of FSM worldwide is large and inequitably distributed amongst the

357

poorest households in both rural and urban areas. Existing piped water networks suggest that the

358

infrastructure for wastewater management may be present for about one out of every five people

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with sanitation facilities without sewerage; however, for the rest of the population, financially-

360

sustainable and logistically-feasible business models for reliable, safe FSM services are needed.

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In all, both wastewater management and FSM represent the next challenge in sanitation service

362

provision to ensure that the sustainable development goals are met and thus improve human

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health and well-being.

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Bassan, M.; Brdjanovic, D.; Dangol, B.; Dodane, P.-H.; Hooijmans, C. M.; Manuel Lopez-Vazquez, C.; Mbeguere, M.; Mikhael, G.; Moya Diaz-Aguado, B.; Niwagaba, C. B.; et al. Faecal Sludge Management; Strande, L., Ronteltap, M., Brdjanovic, D., Eds.; IWA, 2014. Jenkins, M. W.; Cumming, O.; Scott, B.; Cairncross, S. Beyond “improved” towards “safe and sustainable” urban sanitation: assessing the design, management and functionality of sanitation in poor communities of Dar es Salaam, Tanzania. J. Water, Sanit. Hyg. Dev. 2014, 4 (1), 131. Ingallinella, a M.; Sanguinetti, G.; Koottatep, T.; Montanger, A.; Strauss, M. The challenge of faecal sludge management in urban areas--strategies, regulations and treatment options. Water Sci. Technol. 2002, 46 (10), 285–294. Boot, N. L. D.; Scott, R. E. Faecal sludge in Accra, Ghana: problems of urban provision. Water Sci. Technol. 2009, 60 (3), 623–631. Oyoo, R.; Leemans, R.; Mol, A. P. J. The determination of an optimal waste management scenario for Kampala, Uganda. Waste Manag. Res. 2013, 31 (12), 1203–1216. Nelson, K. L.; Murray, A. Sanitation for Unserved Populations: Technologies, Implementation Challenges, and Opportunities. Annu. Rev. Environ. Resour. 2008, 33 (1), 119–151. Ashipala, N.; Armitage, N. P. Impediments to the adoption of alternative sewerage in South African urban informal settlements. Water Sci. Technol. 2011, 64 (9), 1781–1789. Kennedy-Walker, R.; Holderness, T.; Alderson, D.; Evans, B.; Barr, S. Network modelling for road-based faecal sludge management. Proc. Inst. Civ. Eng. Eng. 2015, 167 (ME3), 157–165. Bassan, M.; Mbéguéré, M.; Tchonda, T.; Zabsonre, F.; Strande, L. Integrated faecal sludge management scheme for the cities of Burkina Faso. J. Water, Sanit. Hyg. Dev. 2013, 3 (2), 216. Chowdry, S.; Kone, D. D. Business Analysis of Fecal Sludge Management: Emptying and Transportation Services in Africa and Asia. 2012, No. September, 116. Coffey, D.; Gupta, A.; Hathi, P.; Khurana, N.; Spears, D.; Srivastav, N.; Vyas, S. Revealed Preference for Open Defecation. Econ. Polit. Wkly. 2014, 49 (38), 43–55. Coffey, D.; Gupta, A.; Hathi, P. Culture and the health transition: Understanding sanitation behavior in rural north India; 2014. Tilley, E.; Strande, L.; Lüthi, C.; Mosler, H.-J.; Udert, K. M.; Gebauer, H.; Hering, J. G. Looking beyond Technology: An Integrated Approach to Water, Sanitation and Hygiene in Low Income Countries. Environ. Sci. Technol. 2014, 48, 9965–9970. Fobil, J.; May, J.; Kraemer, A. Assessing the relationship between socioeconomic conditions and urban environmental quality in Accra, Ghana. Int. J. Environ. Res. Public Health 2010, 7 (1), 125–145. Parkinson, J.; Boot, N. Assessing demand for faecal sludge management ( FSM ) services in Freetown. Waterlines 2016, 35 (4), 336–356. Berendes, D.; Kirby, A.; Clennon, J. A.; Raj, S.; Yakubu, H.; Leon, J.; Robb, K.; Kartikeyan, A.; Hemavathy, P.; Gunasekaran, A.; et al. The Influence of Household- and Community-Level Sanitation and Fecal Sludge Management on Urban Fecal Contamination in Households and Drains and Enteric Infection in Children. Am. J. Trop. Med. Hyg. Accepted. Kolsky, P. J.; Butler, D. Solids size distribution and transport capacity in an Indian drain.

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Urban Water 2000, 2 (2000), 357–362. Turley, R.; Saith, R.; Bhan, N.; Rehfuess, E.; Carter, B. Slum upgrading strategies involving physical environment and infrastructure interventions and their effects on health and socio-economic outcomes (Review); 2013. Unger, A.; Riley, L. W. Slum health: From understanding to action. PLoS Med. 2007, 4 (10), 1561–1566. Berendes, D.; Leon, J.; Kirby, A.; Clennon, J.; Raj, S.; Yakubu, H.; Robb, K.; Kartikeyan, A.; Hemavathy, P.; Gunasekaran, A.; et al. Risk factors for pediatric enteric infection in a low-income urban neighborhood in Vellore, India: Examining the contributions of the household environment, neighborhood geography, and exposure behaviors. In Water and Health Conference: Where Science Meets Policy; 2016. Acker, W.; Parkinson, J.; Mabote, M.; Campos, L. C. Assessing health risks associated with municipal sanitation systems in Maputo, Mozambique. Waterlines 2016, 35 (4), 397– 411. Baum, R.; Luh, J.; Bartram, J. Sanitation: A global estimate of sewerage connections without treatment and the resulting impact on MDG progress. Environ. Sci. Technol. 2013, 47 (4), 1994–2000. Zuerbruegg, C.; Tilley, E. A system perspective in sanitation – Human waste from cradle to grave and reincarnation. Desalination 2010, 251 (May 2008), 410–417.

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Table 1: Sanitation coverage and location of drinking water source by country and WHO region among surveyed nations Sanitation coverage and type Sewered FSM needed No facility On-premises piped

All countries (n = 58) Africa (n = 33) Angola Benin Burkina Faso Burundi Cameroon Chad Comoros Dem. Rep. Congo (DRC) Rep. Congo Cote d’Ivoire Ethiopia Gabon The Gambia Ghana Guinea Kenya Lesotho Liberia Madagascar Malawi Mali Mozambique Namibia Niger Nigeria Rwanda Sao Tome and Principe Sierra Leone Tanzania Togo Uganda Zambia Zimbabwe LAC3 (n = 7) Bolivia Colombia Dominican Rep. Guyana

Location of drinking water connection Other onNot on-premises premises/neighbor Total pop.2 Mean %1 Total pop.2 Mean %1 Total pop.2 693,404,785 1.9 146,891,193 70.1 2,348,469,785

Mean %1 14.0

Total pop.2 316,555,344

Mean %1 62.8

Total pop.2 1,774,646,390

Mean %1 21.6

Total pop.2 1,073,001,372

Mean %1 26.3

5.4 7.6 1.3 0.6 1.1 0.8 0.9 5.3 0.2

30,861,856 1,528,842 143,235 114,192 119,586 202,626 102,381 42,351 173,509

65.4 13.2 43.5 50.1 95.9 92.0 28.1 92.4 85.0

577,391,250 2,660,805 4,673,442 9,779,179 10,642,929 22,413,865 3,327,184 733,944 69,136,238

27.5 40.7 54.2 49.0 3.0 7.0 71.0 0.8 14.7

225,737,951 8,208,601 5,823,062 9,567,314 336,784 1,716,622 8,415,066 6,440 11,965,843

17.9 12.7 19.9 13.1 5.1 14.7 5.6 37.9 15.2

96,256,978 2,560,256 2,142,270 2,556,771 564,626 3,585,025 659,492 301,257 12,362,962

0.7 0 0 0 1.8 0 0 0 0

8,640,317 0 0 0 203,615 0 0 0 0

81.4 87.3 80.1 86.9 93.1 85.3 94.3 62.0 84.8

742,524,581 17,612,076 8,599,188 16,954,326 10,329,652 20,769,262 11,172,449 492,167 68,951,625

1.6 6.4 0.6 33.2 2.6 7.8 3.0 10.0 1.4 1.0 0.2 3.5 1.5 0 37.3 0.6 5.5 1.3 5.8

78,910 1,523,470 595,967 577,528 51,282 2,106,401 368,094 4,672,579 28,179 43,968 40,586 649,314 256,438 0 908,277 110,094 10,158,331 165,596 11,391

89.6 60.1 56.4 63.5 95.2 75.2 77.4 81.6 71.4 53.5 43.3 84.2 87.3 58.3 16.0 26.6 65.0 94.0 32.3

4,347,436 14,256,340 57,709,987 1,103,764 1,913,845 20,245,354 9,363,303 38,164,707 1,395,101 2,299,195 10,570,207 15,627,166 15,251,150 15,122,858 389,366 4,949,480 120,960,291 12,206,930 63,850

8.7 33.2 38.3 2.3 2.1 16.9 19.5 8.0 27.1 45.2 56.5 12.2 11.0 41.7 46.3 72.8 29.4 3.9 61.4

421,091 7,892,666 39,230,191 40,217 42,219 4,544,237 2,354,183 3,753,824 529,666 1,942,180 13,798,349 2,267,951 1,924,261 10,807,292 1,127,743 13,566,790 54,741,717 507,909 121,321

25.4 31.5 11.0 63.7 41.5 9.7 22.2 24.2 25.6 1.1 2.8 14.2 8.9 10.8 50.9 7.2 2.8 9.5 30.6

1,231,022 7,471,807 11,273,281 1,108,172 834,865 2,616,601 2,685,567 11,330,076 499,662 46,044 693,069 2,644,986 1,555,712 2,806,116 1,241,232 1,337,438 5,175,068 1,229,950 60,370

0 0 0 0.4 0 0 0 0 0 0 0 0 0 6.3 0 0 0 0 0

0 0 0 6,247 0 0 0 0 0 0 0 0 0 1,641,587 0 0 0 0 0

74.6 68.4 88.9 35.7 58.4 90.3 77.7 75.8 74.4 98.8 97.2 85.8 91.1 82.8 49.0 92.8 97.0 90.5 69.4

3,619,567 16,246,299 91,061,315 620,575 1,172,910 24,291,661 9,402,358 35,460,682 1,453,408 4,250,152 23,737,256 15,925,335 15,911,396 21,482,447 1,192,663 17,301,162 180,531,398 11,753,375 137,171

0.2 0.7 0.1 0.6 10.2 26.8

14,249 348,081 4,120 244,695 1,581,279 3,896,307

77.8 86.6 50.3 93.4 73.5 46.9

4,684,981 45,471,705 3,900,354 35,794,731 11,407,105 6,824,457

21.4 12.3 48.8 5.7 16.2 26.2

1,286,522 6,474,557 3,786,204 2,199,710 2,519,829 3,817,593

3.6 10.8 5.7 6.2 18.1 28.8

218,404 5,658,961 438,616 2,368,910 2,812,463 4,185,926

0 12.6 0 0.5 0 0

0 6,606,672 0 182,196 0 0

96.2 76.6 94.3 93.3 81.7 71.2

5,790,009 40,217,093 7,311,512 3,574,177 12,671,430 10,361,035

31.3 75.0 72.9 4.2

46,342,876 35,415,596 7,731,733 30,981

55.1 20.1 23.7 94.7

44,666,150 9,508,821 2,509,509 697,212

10.0 4.8 3.4 1.0

11,189,454 2,267,916 363,569 7,451

48.5 78.7 83.9 10.6 32.4

78,346,621 8,636,131 39,621,592 1,128,415 238,352

0.5 0 0 0 0

768,541 0 0 0 0

50.9 20.9 16.1 89.4 67.6

40,482,594 2,293,483 7,599,264 9,478,229 497,389

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Haiti Honduras Peru

1.0 34.4 0

108,934 3,055,625 0

73.6 55.9 62.7

7,715,094 4,971,207 19,264,308

25.1 9.4 16.5

2,632,616 834,991 5,082,912

8.6 48.6 76.4

906,134 4,317,778 23,498,159

1.7 0 1.9

174,493 0 594,048

89.6 51.4 21.6

9,391,107 4,574,265 6,648,856

E. Med. (n = 3) Jordan Pakistan Yemen

38.2 60.3 29.6 24.5

71,535,375 4,938,352 59,877,818 6,719,204

46.1 39.7 49.0 49.8

115,771,012 3,245,787 98,880,200 13,645,025

15.5