Water Purification in Emergencies Overview

Compiled by:
Risch Tratschin (seecon international gmbh), Dorothee Spuhler (seecon international gmbh)

Executive Summary

Emergencies push a community’s coping mechanisms to the limit – also in relation to drinking water supply and sanitation facilities. The main health problems after emergencies arise from poor hygiene due to insufficient water supplies and the consumption of contaminated water. Commonly, securing of appropriate water quantity is prior to securing that water quality is at safe drinking water level. According to Sphere Project, the minimum of basic water needs i.e. water intake, hygiene and cooking, amounts to 7.5 litres per day and person. After a first assessment of water needs and water sources as well as existing water distribution networks, the optimal of immediate response is chosen depending on the local conditions and implemented. However, upgrading of the systems for long-term water supply and reconstruction has to be considered already at the beginning.

Introduction

The health of survivors of a natural disaster is exposed to high risk – even if the actual disaster was of short duration. In most disasters and other emergencies, the main health problems are caused by poor hygiene due to insufficient water supply and the consumption of contaminated water (THE SPHERE PROJECT 2011). Water and sanitation (see also sanitation in emergencies overview) are critical determinants for survival immediately after and during the initial stages of a disaster (GWC 2009). Therefore, the availability of sufficient clean water in the immediate aftermath of a disaster is crucial in order to take care of the sick, provide for human consumption and maintain basic hygiene, support search and rescue efforts, and ensure that productive and commercial activities get back to normal. In addition, the lack of water and water facilities often adversely affects the dignity of those caught up in emergencies (GWC 2009).

Emergency Water Supply and Purification: What and How

The general objectives of emergency water supply and purification are (CHALINDER 1994; THE SPHERE PROJECT 2011):

  • To protect water sources in order to minimise the risk of contamination and transmission of water borne diseases (immediate objective);
  • To provide water of a reasonable quantity (immediate objective);
  • To improve the physical and biological quality of the water (medium-term objective);
  • To improve access to supplies through improved water distribution networks and storage facilities (medium-term objective).

After a first assessment of water needs and water sources as well as existing water distribution networks, the optimal of immediate response is chosen depending on the local conditions and implemented. However, upgrading of the systems for long-term water supply and reconstruction has to be considered already at the beginning.

Immediate Assessment of Water Supply

      HOUSE & REED (2004)

Key factors to be considered when selecting the most suitable water treatment process in case of emergencies. Source: HOUSE & REED (1997)     

The first step to provide water in emergencies is an immediate assessment. Questions to be asked are: How many people need water? What are the problems related to water availability and quality now and how will the situation evolve in some time? Which surface or groundwater sources in the area are affected? How is the water quality of these sources, what is their capacity and how far are they away? How can this water be brought to the people in need and what are the possibilities for treatment if required (see also DAVIS & LAMBERT 2002, table 11.1 for a detailed list of questions to be asked)?

The concrete measures to be taken after a disaster depend on the answers to these questions, the geographical and climatic context (cold or warm weather; draught or flooding); the reason for people being without water and type of target groups (refugees, internally displaced persons, returnees who may temporarily be accommodated in camps or temporary housing, or populations whose lives have been modified by the emergency, but have not been displaced, HOUSE & REED 1997).

The on-going assessment of water needs is divided into four typical emergency phases (DAVIS & LAMBERT 2002; CLASEN & SMITH 2005):

Minimum Standards

The standard needs established by the Sphere Project consider 7.5 to 15 litres per day as the basic water needs per person per day in emergencies (THE SPHERE PROJECT 2011). In some situations, only water used for drinking and preparing food needs to be treated, which still amounts to 5.5 to 9 litres (KAYAGA & REED 2011). In refugee situations, the UNHCR calculates 20 litres per person per day for domestic needs and personal hygiene. The absolute minimum amount of water required for survival is 7 litres.

 

Survival needs: water intake (drinking and food)

2.5 – 3 litres per day

Depends on the climate and individual physiology

Basic hygiene practices

2 – 6 litres per day

Depends on social and cultural norms

Basic cooking needs

3 – 6 litres per day

Depends on food type and social and cultural norms

Total basic water needs

7.5 - 15 litres per day

 

The basic survival water needs according to the humanitarian standards defined by the Sphere Project. Source: THE SPHERE PROJECT (2011)

Communal building water needs (e.g. hospitals, administration, etc.) will require extra water (UNHCR 2007). In a refugee/IDP camp these include (UNHCR 2007; WISNER & ADAMS 2002):

  • Health centre, field hospitals, first-aid stations: 40-60 litres/patient/day
  • Feeding centres: 20-30 litres/patient/day
  • Schools: 3 litres/pupil/day
  • Mosque: 2-5 litres/person/day
  • Hand washing at communal latrines and offices: 1-2 litres/user/day for hand washing, and 2-8 litres/cubicle/day for cleaning
  • Operation of water-borne sewerage system: 20-40 litres/person/day
  • Livestock accompanying displaced persons/refugees: 30 litres/day/cow or camel, 15 litres/day/goat or other small animal.

Moreover, basic water needs vary depending on climate, individual physiology of affected people, social and cultural norms, and the degree of displacement (THE SPHERE PROJECT 2011; CHALINDER 1994). Leakages and other losses of water in the catchment, treatment or distribution process and spare capacity for possible new arrivals in a camp situation are to be considered. The more convenient the supply, the higher will be the consumption (UNHCR 2007).

Water Supply and Purification in Emergencies

Depending of the availability of water sources and the needs, different options are going to be chosen and for each type of source and type or predicted use (e.g. cooking, washing, medical care, etc.) the right treatment is considered.

The water may be brought to people in need by existing water distribution networks, which may need to be repaired. Either the water is then distributed at water points with or without treatment (see also camp water supply or water purification in general) depending on the use (e.g. drinking, cooking, washing, etc.). In some cases, organisations also choose to promote point of use treatment that users can apply themselves after they have recovered the water manually from the water points or a water tanker. If distribution via a network is not possible, motorised distribution is a very common method in the first phase of emergencies. However, if possible tinkering water should be avoided, as it is expensive and difficult to organise. Water tinkering should be seen as no more than an interim measure to allow for the development of new water sources or the improvement of existing supplies. If there is no viable solution to the water problem, then people should be relocated (DAVIS & LAMBERT 2002).

 

 

Camp Water Supply and Purification (mobile treatment units)

Point-of-use Water Supply and Purification

Principles

After and during an emergency, a mobile water treatment unit (either pre-assembled or assembled in the field) is brought close to the water source and the people in need and installed and operated by trained staff.

End-users (households and communities) are trained to apply simple multi-barrier methods based on the HWTS approach.

Typical technologies used

Different units available on the market.

Sedimentation, chemical disinfection and flocculation, boiling, SODIS.

Advantages and Disadvantages

Fast to set up

Effective treatment processes

Expensive

Requires knowhow to operate and maintain

Low-cost

Easy-to-use after short introduction briefing

Requires awareness raising and hygiene promotion

High responsibility of user

Comparison of semi-centralised (camp water supply) and small-scale supply in emergencies (first response).

It is important to note that in emergencies, the securing of appropriate water quantity is prior to securing that water quality is at safe drinking water level. Quantity is more related to water sources selection (availability, proximity and sustainability of sufficient water quantity), while quality affects hygiene promotion and all aspects of water safety plans (THE SPHERE PROJECT 2011).

Simply providing sufficient water will not, on its own, ensure its optimal use or impact on public health. In order to achieve the maximum benefit it is imperative that disaster-affected people have the necessary information, knowledge and understanding to prevent water- and sanitation-related diseases and to mobilise their involvement in the design and maintenance of those facilities. Generally, WASH emergency programmes aim at the above mentioned objectives through (THE SPHERE PROJECT 2011):

International Emergency Responses in the WASH Sector

In case emergencies require or trigger international humanitarian interventions, the availability of material resources and organisational preferences often dictate the solutions chosen for emergency water supply in the field. These variations typically include (HOUSE & REED 1997):

References Library

BUTTLE, M.; SMITH, M. (2004): Out in the Cold. Emergency Water Supply and Sanitation for Cold Regions. Leicestershire: Water, Engineering and Development Centre (WEDC), Loughborough University. URL [Accessed: 24.05.2011].

CHALINDER, A. (1994): Water and Sanitation in Emergencies. Good Practice . (= Review 1). London: Overseas Development Institute. URL [Accessed: 23.05.2011].

CLASEN, T.; SMITH, L. (2005): The Drinking Water Response to the Indian Ocean Tsunami, Including the Role of Household Water Treatment. Geneva: World Health Organization (WHO). URL [Accessed: 14.07.2010]. PDF

DAVIS, J.; LAMBERT, R. (2002): Engineering in Emergencies. A Practical Guide for Relief Workers. London: Intermediate Technology Publications, Ltd..

DENG, F. (2007): The Guiding Principles on Internal Displacement. New York: United Nations (UN).

GWC (Editor) (2009): The Human Right to Water and Sanitation in Emergency Situations. The Legal Framework and a Guide to Advocacy. New York: Global WASH Cluster (GWC), Unicef. URL [Accessed: 23.04.2012].

HOUSE, S.; REED, B. (1997): Emergency Water Sources. Guidelines for Selection and Treatment. Loughborough: Water, Engineering and Development Centre (WEDC). URL [Accessed: 13.10.2011]. PDF

KAYAGA, S.; REED, B. (2011): Emergency Treatment of Drinking-Water at the Point of Use. Geneva: World Health Organization (WHO). URL [Accessed: 01.03.2012]. PDF

THE SPHERE PROJECT (Editor) (2011): Humanitarian Charter and Minimum Standards in Humanitarian Response. Bourton on Dunsmore: Practcal Action Publishing. URL [Accessed: 23.04.2012]. PDF

UNHCR (Editor) (2007): Handbook for Emergencies. Third Edition. Geneva: UNHCR Emergency Preparedness and Response Section. URL [Accessed: 17.10.2011]. PDF

UNHCR (Editor) (2008): A Guidance for UNHCR Field Operations on Water and Sanitation Services. Geneva: UNHCR Water and Sanitation Unit. URL [Accessed: 17.10.2011].

WHO (Editor) (n.y.): Household Water Treatment and Safe Storage Following Emergencies and Disasters. pdf presentation. Geneva: World Health Organisation (WHO). URL [Accessed: 30.03.2010]. PDF

WHO (Editor) (2008): Guidelines for Drinking-water Quality, Third Edition. Third Edition incorporating the First and Second Addenda. Geneva: World Health Organization (WHO). URL [Accessed: 23.04.2012]. PDF

WISNER, B. (Editor); ADAMS, J. (Editor) (2002): Environmental Health in Emergencies and Disasters. Chapter 7: Water Supply. A Practical Guide. Geneva: World Health Organization (WHO). URL [Accessed: 27.05.2011]. PDF

Further Readings Library

Reference icon

HOUSE, S.; REED, B. (1997): Emergency Water Sources. Guidelines for Selection and Treatment. Loughborough: Water, Engineering and Development Centre (WEDC). URL [Accessed: 13.10.2011]. PDF

This comprehensive and very well-presented guideline provides much information on the selection and treatment of water sources but also discusses the design and costing of the water supply system, the ordering of material and equipment, the organisation of human resources, and the implementation of projects.


Reference icon

OXFAM (Editor) (2001): Oxfam Guidelines for Water Treatment in Emergencies. Oxford: Oxfam GB. URL [Accessed: 25.05.2011]. PDF

OXFAM with its long-standing experience in WASH emergencies outlines within these guidelines a comprehensive overview about assessing water quality, treatment technologies, application, installation strategies for bulk water supply and additionally the operation and monitoring of such facilities during emergency operations.


Reference icon

THE SPHERE PROJECT (Editor) (2011): Humanitarian Charter and Minimum Standards in Humanitarian Response. Bourton on Dunsmore: Practcal Action Publishing. URL [Accessed: 23.04.2012]. PDF

The Sphere Project is an initiative to determine and promote standards by which the global community responds to the plight of people affected by desasters. This handbook contains a humanitarian charter, protection principles and core standards in four disciplines: Water, sanitation and hygiene; food security and nutrition; shelter, settlements and non-food items; and health action.


Reference icon

UNICEF (Editor) (2008): UNICEF Handbook on Water Quality. New York: United Nations Children's Fund (UNICEF). URL [Accessed: 30.03.2010]. PDF

This handbook is a comprehensive a new tool to help UNICEF WASH field professionals, but it will also be useful to other UNICEF staff and for partners in government, other external support agencies, NGOs and civil society. The handbook provides an introduction to all aspects of water quality, with a particular focus on the areas most relevant to professionals working in developing countries. It covers the effects of poor water quality, quality monitoring, the protection of water supplies, methods for improving water quality, and building awareness and capacity related to water quality.


Reference icon

WHO (Editor); WEDC (Editor) (2013): Technical Notes on Drinking-Water, Sanitation and Hygiene in Emergencies. Geneva: World Health Organization (WHO). URL [Accessed: 27.08.2013]. PDF

These technical notes are relevant to a wide range of emergency situations, including both natural and conflict-induced disasters. They are suitable for field technicians, engineers and hygiene promoters, as well as staff from agency headquarters.


Reference icon

GLOBAL WASH LEARNING PROJECT (Editor) (2008): Lessons Learned in WASH Response During Urban Flood Emergencies. New York: Global WASH Cluster. URL [Accessed: 23.04.2012]. PDF

This paper identifies various lessons that can be learned from urban flood emergencies, with a focus on the WASH sector. It includes urban flood management issues in emergencies related to water, sanitation, hygiene and various crosscutting issues.


Reference icon

GLOBAL WASH LEARNING PROJECT (Editor) (2009): Lessons Learned in WASH Response During Rural Flood Emergencies. New York: Global WASH Cluster. URL [Accessed: 27.08.2013]. PDF

This paper identifies various lessons that can be learned from the experiences of relief agencies when responding to rural flooding emergencies. It includes background information on flood emergencies and challenges of WASH response to rural floods and is intended for WASH technical advisors and personnel involved in planning and delivery of WASH programmes in rural flood emergency situations.


Reference icon

HARVEY, B. (2012): Water, Sanitation and Hygiene (WASH) in Health-Care Facilities in Emergencies. Technical Notes on Drinking-water, Sanitation and Hygiene in Emergencies. (= Technical Notes on Drinking-Water, Sanitation and Hygiene in Emergencies, 17). Geneva: World Health Organization (WHO). URL [Accessed: 30.09.2013]. PDF

Health-care facilities play a vital role within the community by providing essential medical care at all times including during emergencies. Any incident which causes loss of infrastructure, energy supply, loss of equipment, loss of staff or staff attrition, interruption to supply chains, or patient surge - such as sudden communicable disease epidemics, natural disasters (e.g. floods, earthquakes), or conflict - requires a holistic health response and recovery effort which includes actions to assess and restore basic WASH services.


Reference icon

WHO (Editor) (2011): Guidelines for Drinking-water Quality, Fourth Edition. Geneva: World Health Organization (WHO) . URL [Accessed: 08.08.2011]. PDF

This volume of the Guidelines for Drinking-water Quality explains requirements to ensure drinking-water safety, including minimum procedures and specific guideline values, and how those requirements are intended to be used. The volume also describes the approaches used in deriving the guidelines, including guideline values. It includes fact sheets on significant microbial and chemical hazards.


Case Studies Library

Reference icon

CLASEN, T.; SMITH, L. (2005): The Drinking Water Response to the Indian Ocean Tsunami, Including the Role of Household Water Treatment. Geneva: World Health Organization (WHO). URL [Accessed: 14.07.2010]. PDF

This study documents the drinking water response, including the role played by household water treatment after the Indian Ocean Tsunami.


Awareness Raising Material Library

Reference icon

YATES, T. ; VIJCIC, J.; JOSEPH, M. L.; LANTAGNE, D. (2016): Impact of WASH Interventions During Disease Outbreaks in Humanitarian Emergencies. A Systematic Review Protocol. Oxford, UK: Oxfam. URL [Accessed: 04.05.2016]. PDF

The purpose of this document is to clearly describe the proposed research questions and methodology for a systematic review on water, sanitation, and hygiene (WASH) interventions in disease outbreaks. The systematic review has a singular overarching objective in assessing the impact of emergency hygiene interventions.


Training Material Library

Reference icon

OXFAM (Editor) (2000): Water, Sanitation, and Shelter Equipment. For Emergencies and Longer Term. Oxford: Humanitarian Department Oxfam. URL [Accessed: 13.10.2011]. PDF

This short manual describes purpose, development and use of standard water and sanitation equipment packages of OXFAM, as well as individual packages for water storage, water pumping, borehole drilling, but also excreta disposal and shelter equipment. These measures can serve urgent but also longer term needs.


Important Weblinks

http://www.watersanitationhygiene.org/ [Accessed: 09.08.2011]

This forum features comments and discussions on topics of emergency water e.g. water treatment units, storage, distribution equipment, transport and many more.