What actions are most urgent in relation to water, sanitation and health?
The three top priorities are the provision of sufficient quantities of safe water, basic sanitation arrangements and promotion of good hygiene behaviours.
The first priority is to provide an adequate quantity of water, even if its safety cannot be guaranteed, and to protect water sources from contamination. A minimum of 15 litres per person per day should be provided as soon as possible, though in the immediate post-impact period, it may be necessary to limit treated water to a minimum of 7.5 litres per day per person. During emergencies, people may use an untreated water source for laundry, bathing, etc. Water-quality improvements can be made over succeeding days or weeks.
Major health risks due to inadequate excreta disposal arise after disasters. Where normal sanitation structures have been damaged or destroyed it is essential to provide toilet facilities immediately. Emergency facilities are usually provisional and need to be progressively improved or replaced as the situation develops.
Following damage to existing systems, or when parts of a city receive large numbers of displaced or homeless people, so putting increased pressure on facilities that may already be under strain, a rapid assessment of damage and needs is required to decide what emergency actions to take.
Designated defecation fields or areas can be used where enough space is available. These work best in hot, dry climates and should be clearly marked, fenced (if possible), and protected against flooding. They should be located downwind and away from living areas, avoid water courses, and at a reasonable distance (minimum 50m) from water points. Shovels should be provided to families so that they can dig small holes to defecate into and cover their faeces with soil.
Collective trench latrines may also be an option. In longer term situations or after the initial emergency period has subsided, it may be more practical to build simple pit latrines, ventilated improved pit (VIP) latrines, or poor-flush latrines. In situations where the soil is rocky or the ground water is very close to the surface, elevated platforms may be constructed. Latrines of all types need to be properly cleaned and maintained. Responsibilities for cleaning and maintaining latrines should be clearly spelled out. For collective latrines it may be necessary to hire someone to take care of them.
The immediate response may also include establishing or reinforcing sewage evacuation services, to bypass blocked sewers or to carry out intensive septic tank or latrine emptying in periurban areas. Every effort should be made to allow people to use their existing toilets, through temporary repairs to broken sewers and sewage treatment works.
In all cases, good hygiene practices are very important for preventing disease transmission. Water should be provided in sufficient quantities to enable proper hygiene. Hands should be washed immediately after defecation, after handling babies' faeces, before preparing food and before eating.
Other environmental health interventions might be crucial as indicated in the subsequent questions and answers.