Development of a Generic Domestic Water Security Index, and Its Application in Addis Ababa, Ethiopia PDF

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water Article Development of a Generic Domestic Water Security Index, and Its Application in Addis Ababa, Ethiopia Yonas T. Assefa 1,2 , Mukand S. Babel 1, *, Janez Sušnik 2 and Victor R. Shinde 1 1 Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology...

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Development of a Generic Domestic Water Security Index, and Its Application in Addis Ababa, Ethiopia Yonas T. Assefa 1,2 , Mukand S. Babel 1, *, Janez Sušnik 2 1 2

*

and Victor R. Shinde 1

Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, Pathumthani 12120, Thailand; [email protected] (Y.T.A.); [email protected] (V.R.S.) Integrated Water Systems and Governance Department, IHE Delft Institute for Water Education, 2601 DA Delft, The Netherlands; [email protected] Correspondence: [email protected]

Received: 21 October 2018; Accepted: 18 December 2018; Published: 25 December 2018







Abstract: Water security is a global concern because of the growing impact of human activities and climate change on water resources. Studies had been performed at global, country, and city level to assess the water security issues. However, assessment of water security at a domestic scale is lacking. This paper develops a new domestic water security assessment framework accounting for water supply, sanitation, and hygiene through twelve indicators. Water supply, sanitation, and hygiene are central to key water-related sustainable development goals. The framework is subsequently applied to the city of Addis Ababa, Ethiopia. From the domestic water security assessment of Addis Ababa, the water supply dimension was found to be of good level, whereas the sanitation and hygiene dimensions were of poor and fair level, respectively, indicating both a challenge and an opportunity for development. Because the analysis is spatially explicit at the city-branch level (in Addis), variation in domestic water security performance across Addis Ababa can be assessed, allowing efficient targeting of scant resources (financial, technical, personnel). Analysis further shows that a lack of institutional capacity within the utility, existing infrastructure leading to ‘lock-in’ and hindering maintenance and upgrade initiatives, and an unreliable power supply are the main issues leading to poor domestic water security in the study city. These areas should be tackled to improve the current situation and mitigate future problems. The developed framework is generic enough to be applied to other urban and peri-urban areas, yet provides planners and policy makers with specific information on domestic water security considering water supply, sanitation and hygiene, and accounting for within-city variability. This work could therefore have practical applicability for water service providers. Keywords: developing cities; domestic water security; Ethiopia; hygiene; sanitation; urban water security; water supply

1. Introduction “Water security is the capacity of a population to safeguard sustainable access to adequate quantities of acceptable quality water for sustaining livelihoods, human well-being, and socio-economic development, for ensuring protection against water-borne pollution and water-related disasters, and for preserving ecosystems in a climate of peace and political stability” [1]. Securing drinking water supply is one of the fundamental components in urban water security, and delivery of clean water and sanitation is one of the sustainable development goals (SDG6). However, meeting drinking water demands is becoming a big challenge globally, particularly in developing countries, due to an increase in consumption that is driven by urbanization, rapid population growth, economic growth, and change in local climate [2]. Water 2019, 11, 37; doi:10.3390/w11010037

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Currently, about 1 in 2 people is an urban dweller and by 2030 about 60% of the population are expected to live in cities, partially contributing to an expected water consumption increase of 55% by 2050 [3]. In addition, low-income countries are expected to be the most affected by climate change and the impact on securing water resources [4]. Sub Saharan and eastern Africa are particularly exposed to climate change impacts [5]. Ethiopia is one of the Horn of Africa countries which is currently most exposed to droughts. It follows that rapidly expanding urban areas in lower income countries face considerable water supply and sanitation challenges in the near future. Addis Ababa, Ethiopia, is no different. The city is home to more than 25% of the urban population of Ethiopia and is one of the fastest growing cities in Africa [6]. Ndaruzaniye [5] reports that investment in the water supply and sanitation coverage has not followed population growth. As a result, the water supply service only covers 55% of the city area, half of the population is served for less than 12 h per day, and a quarter of the population have no formal service at all [5]. More recent studies show that the city still suffers similar water supply problems [7,8]. Although studies have been performed to identify the major factors affecting water security [9,10], a fundamental challenge is developing a general method to measure water security that also yields city-specific information. One of the main reasons making it difficult is that water security is broadly defined and is a combination of various aspects which vary at different scales. For example, Vörösmarty et al. [11] assessed water security on a global scale, considering human water security and biodiversity. On the other hand, the national scale is also commonly used. A common framework for water security assessment at the country level is a framework with five key dimensions, chosen for their simplicity, developed by the Asian Water Development Outlook (AWDO) [12,13]. It has been applied in 49 ADB member countries in Asia and the Pacific. A recent study in assessing water security at city level was conducted by Babel et al. [14]. The research establishes a framework with five components of water security, and was applied in Bangkok, Thailand. It is shown that the indicators are good in representing water security at the city level in which they considered domestic water security, water productivity, security against water-related disasters, environmental water security, and governance and management aspects. The proportion of piped water supply, water consumption, and proportion of safe drinking water were considered to evaluate the domestic water security. A similar city-level study, but lacking in sub-city detail, was carried out by Jensen and Wu [15]. In most water security assessment studies, domestic water security is studied as one component or dimension. Access to improved water supply and sanitation was taken as an indicator to assess domestic water security [16]. A recent study which solely focuses on the household level domestic water security used the following indicators: piped water coverage, improved sanitation coverage, and hygiene (number of age-standardized disability-adjusted life years (DALYs) per 100,000 people for the incidence of diarrhea) [13]. Measuring the water security at the global or national level will only give the general picture of the situation from a countrywide standpoint, not from a local perspective [17]. Accordingly, assessing the specific water supply and sanitation components at the local level will be helpful for considering detailed challenges and opportunities for the domestic water security situation. According to Babel et al. [14], domestic water security is one of the water security components which needs to be assesssed at the local level. In most of the assessments, only a few indicators were considered to evaluate the domestic water security of a city. However, those indicators give a limited picture of the challenge on water security. Thus, improved indicators are required to investigate the water security situation at the domestic level. The biggest challenge in assessing domestic water security is the lack of a well-organized framework. This paper develops a domestic water security framework to include water supply, sanitation, and hygiene to determine domestic-level water security, and applies it to Addis Ababa to assess the current

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domestic water security situation. Because the developed framework is generic, it can be readily applied to other cities globally while retaining locally relevant information. 2. Development of a Domestic Water Security Framework 2.1. Definition of Domestic Water Security Domestic water security is the ability of a population to safeguard sustainable access to adequate quantities of and acceptable quality water for the basic household needs of drinking, sanitation, and hygiene. Although it can be argued that water security is a much broader issue incorporating aspects such as crises and emergency planning and response, addressing vandalism and terrorist acts, development of warning and monitoring systems, ecosystem preservation, and mitigation against water-related hazards, in this paper, the focus is very much on the water security at a household level. It is, therefore, centered on the water supply, sanitation, and hygiene dimensions of domestic water security. 2.2. Structure of the Framework The developed framework has three levels of information for water security assessment: dimensions, indicators, and variables. Dimensions are the various broad components of domestic water security. Numerous indicators are used to represent the dimensions of domestic water security. Variables are then identified to quantify the indicators (Table 1). Table 1. Dimensions, indicators, and definition of variables for this study. Dimension, i

Indicator, j

Variable, k

What Is Assessed?

Measurement Unit

Availability

The available volume of water resource for drinking purpose

Is the available water sufficient to fulfill the required water demand for the household purpose?

m3 cap−1 year−1

Accessibility

Improved water supply (treated and piped water supply) Water supply service duration

Is the accessibility of water supply service good enough in terms of access to piped water supply and service duration?

% people with access to network Hours of service

Quantity

Adequate water for domestic consumption (per capita consumption)

Is the supplied water adequate enough to satisfy the required water consumption?

L cap−1 day−1

Quality

Acceptable water quality for human health

How well is the supplied water quality for the health of human beings?

pH, mg L−1 , NTU

Affordability

Water tariff

Is the cost of water affordable to all types of community?

US$ m−3

Water management efficiency

Water loss (NRW)

Is the distributed water reaches efficiently to the consumers?

% NRW in the network

Accessibility

Improved sanitation system in terms of customers who use sewerage system

Is the sanitation service good enough in terms of access to improved sanitation coverage?

% people with access to network

Quantity

The amount of wastewater generated

Are the available treatment plants adequate enough to treat the produced wastewater?

m3 , m3 cap−1 year−1

Quality

Quality of the effluent

Are the effluent water quality parameters fulfilling the required standards?

pH, mg l−1 , NTU

Affordability

Affordability of domestic wastewater collection (tariff)

Is the cost for wastewater transportation affordable to all the communities?

US$ m−3

Water availability for hygiene

Is the supplied water adequate to fulfil the required amount for hygiene?

m3 cap−1 year−1

Is there diarrheal problem due to lack of water and poor toilet facilities (lack of hygienic toilet)?

Toilets per number of people

Is the population aware of about hygiene?

Questionnaire responses

Water Supply

Sanitation

Hygiene

Adequacy of water for hygiene

Awareness

The dimensions of domestic water security were established based on the Sustainable Development Goals of clean water and sanitation (SDG6). The dimensions for this study are: (i) water supply; (ii) sanitation; and (iii) hygiene. These three dimensions are represented by numerous indicators, which are measured via the variables (Table 1). More than one variable can be used to assess an indicator. Many indicators combine to represent dimensions. Table 1 details the dimensions,

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Is the cost for wastewater transportation affordable to all the US$ m−3 communities? Water 2019, 11, 37 4 of 23 Is the supplied water adequate to fulfil m3 cap−1 year−1 the required amount for hygiene? Adequacy of Is there diarrheal problem due to lack per number of the associated indicators, and the variables related to the indicators. It also providesToilets definition of each Hygiene water for of water and poor toilet facilities (lack people of them. Figure 1 shows how the variables, indicators, and dimensions are related to form the overall hygiene Awareness of hygienic toilet)? Is the population awaredetails of aboutabout each Questionnaire domestic water security index. The rest of this section provides more indicator and hygiene? responses how it is calculated or assessed in this work. Affordability

Affordability of domestic wastewater collection (tariff) Water availability for hygiene

Figure 1. developed The developed domestic water security index framework. Figure 1. The domestic water security index framework.

2.3. Water Supply Dimension 2.3. Water Supply Dimension 2.3.1. Per Capita Freshwater Availability 2.3.1. Per Capita Freshwater Availability The available water resources should be adequate for different domestic and non-domestic The water resources should be adequate for water different domestic non-domestic stress index and to measure wateruses. scarcity. uses.available Many studies use the Falkenmark et al. [18] Many studies use the Falkenmark et al. [18] water stress index to measure water scarcity. According 3 − 1 − 1 According to this index, water availability...