I. Introduction

The modern concept of sustainable development has emerged in the 1980s as the need for

environmental protection was recognised in the practices of development planning around the world

(Cobbinah et al., 2015). Widely used definition of sustainable development is by Brundtland

Commission, which defines it as development that “[meets] the needs of the present without

compromising the ability of future generations to meet their own needs” (Satterthwaite, 1997). As

various problems have appeared in this urbanising world, sustainable development was perceived as

a paradigm shift and a new notion of development (Du Pisani, 2006).

Achieving sustainable development in cities require a number of factors that play a significant role,

such as sustainable consumption of finite resources and implementation of renewable resources. For

instance, the provision of water and sanitation systems in cities serves as a crucial part in the

sustainable development of cities. Especially in the developing countries, rapid urbanisation has

caused uncontrolled growth of population, causing numerous problems such as increase in urban

density, vulnerability, insecurity, and poverty (Cobbinah et al., 2015). This further creates uncontrolled

and unplanned growth of slums, and insufficient provision of water and sanitation systems aggravate

the situation.

i. Research Background

According to UNICEF and WHO (2019), 1 in 3 people do not have access to safe drinking water, and

around 3 billion people lack basic handwashing facilities with soap and water. This is a major issue

especially for the countries in the Global South. Particularly, the low-income groups of the society,

many living in slum areas, do not have the privilege to be connected to centralised water infrastructure.

A recent report by the World Resources Institute on 15 cities in the Global South, including Lagos,

Mumbai and Caracas, states that 42% of the households in these cities lack access to in-house piped

water (McDonnell, 2019). Moreover, it is also reported that the number of residents in the urban areas

that lack access to piped water has increased by over 200 million since 1990. In urban slum areas,

those who do not have access to in-house piped water often get water from a tanker truck. In the case

of Mumbai, however, the cost of the water from the tanker truck is 52 times more expensive than the

water from public pipe (McDonnell, 2019).

It is not just the problem of in-house piped freshwater supply that these slums lack of, but most of the

cases they also lack of proper sanitation and wastewater management systems. Cornell University

(2019) also referred to the report by the World Resources Institute, and stated that 62% of sewage

and faecal sludge is unsafely managed in the above mentioned 15 cities. They further reported that

according to WHO, the number of people who lack well-managed sanitation in cities has increased

more than 20% since the 2000, from 1.9 billion to 2.5 billion, around the world, and that it is expected

to reach 6 billion by 2030. In the case of India, 120,000 tonnes of faecal sludge is produced daily, but

only around one-third of the toilets are connected to the sewer system (Sivaramakrishnan, 2019). This

means that, most of the human waste is dumped on open land and in water, contaminating the natural

resources. According to Sivaramakrishnan (2019), inadequate urban sanitation and wastewater

management can greatly affect not only the health of the residents, but also a country’s economic

growth and productivity, as well as the natural environment of our planet.

According to United Nations (2018), “universal access to safe, affordable drinking water and basic

sanitation has a direct effect on urban development, providing higher standards of living and health,

and better conditions in the living environments of cities.” United Nations (n.d.) 2030 Agenda for

Sustainable Development Goals (SGDs) clearly shows the correlation of ‘Goal 6: Clean water and

sanitation for all’ and ‘Goal 11: Sustainable cities and communities.’ Currently, a large proportion of

the world’s population is already living in cities. Hence if SDGs 6 and 11 can be realised, they will

become increasingly symbiotic (United Nations, 2018). For instance, the indicator for Target 11.1

addresses upgrading of slums and ensuring access to “adequate, safe and affordable housing and

basic services” to all, including water and sanitation (Rudd et al., 2018; United Nations, n.d.). The

achievement of Target 11.1 will directly contribute to achievement of SDG 3 on good health and well-

being and SDG 5 on gender equality, and further indirectly contribute to other SDGs.

In most parts of the developed world, water and wastewater systems are centralised by the

government and the private sector (Sitzenfrei and Rauch, 2014). Many developing countries have also

adapted the centralised water infrastructure, mainly in the urban areas; however, in the case of low-

income areas, it is difficult to rely on the centrally managed water systems, because of the

inconsistency in the provision due to political manipulation and deliberate overlooking of the slum

areas by the municipality (De and Nag, 2016). The lack of water infrastructure in urban slums not only

generates potential health risks and environmental problems for the residents, but this further affects

their economic capabilities. According to Nhapi (2004), the concept of decentralised water and natural

treatment of wastewater systems suits developing countries because they are more financially

affordable, as well as socially responsible, and better for the environment.

ii. Research Aims and Objectives

The overall aim of this research is to explore the potential of decentralised water infrastructure in

urban slums in developing countries and how this contributes to sustainable development of cities.

This research will focus on two African cities—Nairobi, Kenya and Lagos, Nigeria. Case studies of

implementations of decentralised water infrastructure in the slums of each city for the time period of

2000-2020 will be conducted. Within the context of decentralised water infrastructure, the objectives of

this research are to:

1. Identify different approaches of decentralised water and sanitation systems in urban slums.

2. Analyse and evaluate the feasibility of each approach of the decentralised systems.

3. Investigate the social, economic, and environmental impacts on the development of that city.

4. Propose policy suggestions for the city municipality for revitalisation of the decentralised

water and sanitation systems in low-income areas.