Water Supply Failure

Primary reference(s)

UN-Water, no date. Water Scarcity. Accessed 10 November 2020.

Franchin, P. and F. Cavalieri, 2013. Seismic vulnerability analysis of a complex interconnected civil infrastructure. In: Handbook of Seismic Risk Analysis and Management of Civil Infrastructure Systems. Woodhead Publishing Series in Civil and Structural Engineering, pp. 465-513 514e.

Jain, R., M.K. Camarillo and W.T. Stringfellow, 2014. Drinking water security for engineers, planners, and managers: Integrated water security series. Butterworth-Heinemann.

Additional scientific description

A water supply system loss of safety may result from: failure of its individual subsystem or elements such as water intakes, pumping stations, the water distribution network or its utilities; failure of other technical systems such as sewerage, energy, water structures; extreme natural hazards such as floods and droughts; poor organisational structures; and from incidental pollution of water sources (Pietrucha-Urbanik and Tchórzewska-Cieślak, 2018).

A water supply system failure generally results in a decreased amount of water supplied with inadequate parameters such as low pressure which could lead to water scarcity. Public water system bodies have the responsibility of maintaining physical and human infrastructure to supply water and are often bound by regulations. However, water use has been increasing globally at more than twice the rate of population growth over the past century. Some regions are reaching the limit at which services can be sustainably delivered. In the latter half of the twentieth century, there was an increase in major accidents and disasters relating to the functioning of public water supply systems in rural, urban and industrial areas (Pietrucha-Urbanik, 2015). Failures in water supply systems, treatment processes, and distribution networks can often lead to water contamination incidents, some of which result in disease outbreaks.

As the global population rises, there is a need to balance competing demands on water resources to provide basic necessities for operation and survival. In order to keep up with demand, water supply systems require periodic inspections, maintenance and repairs. Inspections allow for early detection of potential damage, with planning for repair to prevent negative and ongoing consequences associated with the lack of water supply (Pietrucha-Urbanik and Tchórzewska-Cieślak, 2018). Recent practice to reduce the number of emergency failures, has been the implementation of preventative renewal. This identifies the elements within the water supply systems that are most vulnerable to failure and ensures that they are replaced, thereby reducing the probability of failure (Pietrucha-Urbanik and Tchórzewska-Cieślak, 2018). This has largely been applied for aging infrastructure. Actions taken to reduce the number of water supply system failures include but are not limited to: technical renewal of pipelines (renovations, maintenance and diagnostics); replacement of pipes and fittings; improvements in detecting places of leaks; network pressure limitation to the lowest permissible value; and proper operation, design and execution of water supply systems.

Metrics and numeric limits

While significant progress has been made towards improving water supply infrastructure and achieving access to basic water, sanitation and hygiene, gaps remain in the quality of services provided. A recent report concluded that 1.8 billion people have gained access to basic drinking water services since 2000, but there remains vast inequalities in the accessibility, availability and quality of these services and more than 2 billion people around the world do not have safely-managed drinking water (UN-Water, no date a).

Examples of drivers, outcomes and risk management

Water is essential for socio-economic development, energy and food production, healthy ecosystems and human survival. Access to safe drinking water is a major global health concern and water is also considered at the core of adaptation to climate change, providing the crucial link between society and the environment.

In recent decades, analyses and assessments of water system failures have been conducted in many countries, concluding that assessments have been used to improve programming, design, implementation and operation, and to inform and/or amend technical regulations, design standards, guidelines and instructions for the performance and acceptance of facilities of water supply systems (UN-Water, no date a).

Integrated water resources management, which has been accepted internationally, provides a broad framework for governments to align water use patterns with the needs and demands of different users (UN-Water, 2008).

In addition to Integrated Water Resources Management, a number of regulations and standards have been developed to address water supply security and safety, particularly from the World Health Organization in regards to the applications of water safety plans, some of which include:

• Water sanitation hygiene: Global water supply and sanitation assessment 2000 report (WHO, 2000a).
• Operation and maintenance of rural water supply and sanitation systems A training package for managers and planners (WHO, 2000b).
• Global costs of attaining the Millennium Development Goal for water supply and sanitation (WHO, 2008).
• Vision 2030: The resilience of water supply and sanitation in the face of climate change Summary and policy implications (WHO, 2009).
• Guidance on water supply and sanitation in extreme weather events (WHO Regional Office for Europe, 2012).

The United Nations (UN) seeks to support countries in monitoring water and sanitation related issues within the framework of the 2030 Agenda for Sustainable Development and in compiling country data to report in global progress toward Sustainable Development Goal 6 (SGD6). The aim of this initiative is to increase the availability of high quality data to inform evidence-based policymaking, regulations and planning investments at all levels.

UN-Water has developed a global data portal ‘The SDG 6 Data Portal’ which brings together all the UN’s water and sanitation information to show the global status on Indicator 6.4.1: Change in water-use efficiency over time. The objective of the portal is to: track overall progress towards SDG6 at global, regional and national levels; enable assessment and analysis of the state of water resources and linkages to other sectors; raise awareness of water and sanitation issues to help catalyse action; and encourage and improve SDG6 monitoring and reporting at all levels (UN-Water, no date b).