WASH in Emergencies: What to Deliver in the First 72 Hours

Tony Miller

Oct 2

6 min read

In the first 72 hours of an emergency, deliver in this order: safe water at about 15 litres per person per day, toilets, handwashing with soap, then hygiene supplies. UNHCR's emergency targets put the water floor at 15 litres per person per day, within 500 m of every household. Everything else is sequencing around that number.

What does WASH in emergencies actually have to achieve in 72 hours?

It has to stop faecal matter reaching mouths. That is the whole job. Microbiologically contaminated drinking water is estimated to cause approximately 505,000 diarrhoeal deaths each year, per the WHO drinking-water fact sheet of 13 September 2023, and WHO states that access to safe water, basic sanitation and hygiene is essential to prevent cholera. A displaced population that is thirsty, crowded and defecating near its water source is the exact condition those figures describe.

Note that "72 hours" is a planning window, not a standard. Sphere and UNHCR set minimums, not deadlines. We use 72 hours because it is the point by which a field team either has a working water point and a first set of latrines on the ground or has lost the initiative to the outbreak. The order of work below is our operating view, built on those published minimums.

What are the minimum numbers to plan against?

Plan against these, and say which source you used in your assessment:

Water quantity: UNHCR's January 2020 WASH indicators and targets set an emergency target of at least 15 litres of potable water per person per day, rising to 20 in the post-emergency phase. The IFRC's summary of the Sphere standards gives total basic water needs of 7.5 to 15 litres per day, made up of 2.5 to 3 litres for drinking, 2 to 6 for hygiene and 3 to 6 for cooking.
Distance and queueing: a maximum of 500 m from household to water point in the emergency phase, per UNHCR, and a 30 minute queueing limit in the Sphere summary.
Water points: no more than 250 people per usable tap on a centralised system, and 500 per handpump, well or spring, per the UNHCR targets.
Toilets: UNHCR's emergency target is no more than 50 people per toilet, tightening to 20 after the emergency phase. The IFRC's Sphere summary lists fewer than 20 users per toilet.
Soap: UNHCR states that at least 450 grams of soap should be distributed per person per month, of which 250 grams is for personal hygiene and 200 grams for laundry and other washing.
Water quality: the Sphere summary sets free residual chlorine of at least 0.5 mg/L after 30 minutes contact at pH below 8, and no less than 0.2 mg/L at the point of delivery, with turbidity of 5 NTU or less.

The two sources frame water differently: the Sphere summary gives a range of 7.5 to 15 litres, while UNHCR sets 15 as its emergency target. Plan for 15. If you plan for the bottom of the range you will be short the day cooking and washing begin.

What goes first: water, sanitation or hygiene?

Safe water, then excreta, then hands, then the rest. That order is deliberate, and it is a view some teams argue with, so here is the reasoning.

Safe drinking water (hours 0 to 24). People will drink from whatever is nearest. Putting treated water within reach removes the biggest transmission route fastest, and it is the item you can scale by tonnes rather than by construction.
Excreta control (hours 12 to 48). Latrines take digging, slabs, privacy walls and land agreements, so they must start while water is still being set up. Contamination of the water source from open defecation undoes the treatment you just installed.
Handwashing (hours 24 to 72). Handwashing needs water, soap and a place to stand. It follows the first two because it depends on them, but it has to be in place at latrines and food areas before day three ends. Our deeper guide to handwashing stations in an outbreak covers the specification.
Hygiene supplies and promotion (hours 48 to 72 and onward). Soap, buckets, covered containers and menstrual hygiene materials, with hygiene promoters briefed on the same day the supplies land.

How do you get safe water flowing in the first 24 hours?

Treat at point of use first, then build up to piped or trucked supply. A household tablet needs no infrastructure. One Aquatabs 67 mg tablet treats 8 to 10 litres of clear water, with 30 minutes before use, per the CDC-hosted instruction sheet for the Medentech product. Cloudy water should be settled or filtered first, which is where a flocculant-disinfectant sachet such as P&G Purifier of Water is the better choice for turbid flood or river water.

The catch is storage. In a Bulletin of the WHO study in South Sudan refugee camps, 40 to 58 percent of households collecting water from chlorinated sources had no detectable residual chlorine in their stored water, and the authors recommended raising the free residual chlorine guideline to 1.0 mg/L. Treated water that arrives in an open bucket is untreated again by evening. So the first-72-hour kit is not tablets alone: it is tablets plus covered, narrow-necked containers, plus someone testing residual at the tap.

For a communal supply, you need bulk storage between the source and the tapstand. Oxfam's standard steel tank comes in 11, 45, 70 and 95 cubic metre sizes with PVC or EPDM liners, and Oxfam notes that the range has been deployed in humanitarian responses for 40 years. Pick the size from your population multiplied by 15 litres, for the number of days of buffer your trucking cycle needs. Our companion guide on WASH preparedness for flood-season field teams shows how that sizing changes when roads close.

What does the first-72-hour equipment list look like?

Match each priority to something you can ship, and be honest about what is not in your supply chain:

Household treatment: Aquatabs 67 mg tablets for clear water, P&G Purifier of Water for turbid water.
Bulk storage: Oxfam steel tanks and Butyl bladder tanks, so a trucked or pumped supply has a buffer and a chlorination point.
Pumping: Multiquip and Aussie Pumps for lifting water from borehole or surface source into storage.
Residual testing: a field comparator or DPD kit at every water point, so you know whether the dose held.
Latrine and hygiene programme items: latrine slabs, soap, buckets and hygiene kits are standard in the sector but are not part of the SLS range. Source them from the cluster pipeline or your agency's stock, and plan their arrival dates against the water kit.

The gap between the list above and what actually reaches the site is nearly always transport and customs, not manufacturing. That is where in-country stock matters.

What mistakes cost teams the first 72 hours?

Three recur.

Treating water without a residual test. A tablet that was dosed correctly and is not measured gives false confidence. Free residual chlorine at the tap is the only evidence that the water is protected.
Sizing storage to the average day. Demand spikes after the first day, when cooking and washing begin. Size to 15 litres, not 7.5.
Siting water points and latrines without checking each other. A latrine uphill of a water point, or a tapstand in a flood path, turns a delivered asset into a hazard.

Why does in-country stock change the answer?

Because the 72-hour window is shorter than most import lead times. In the 2024 to 2025 South Sudan cholera response we deployed more than 52 million Aquatabs tablets and 3.28 million P&G Purifier of Water sachets, run through procurement, customs clearance, Juba warehousing and last-mile delivery. Those are distribution figures, not measures of water consumed. The point they make is that outbreak-scale supply only works when stock is already in the country. See the SLS case studies for the full delivery chain.

Frequently asked questions

How much water does a person need in an emergency?

UNHCR's emergency target is at least 15 litres of potable water per person per day, rising to 20 after the emergency phase. The IFRC's Sphere summary gives 7.5 to 15 litres as total basic water needs, so plan for the top of the range.

How many people can share one toilet in the first days?

UNHCR's emergency target is no more than 50 people per toilet, tightening to 20 in the post-emergency phase. The IFRC's Sphere summary lists fewer than 20 users per toilet.

What chlorine residual should safe emergency water have?

The Sphere summary sets at least 0.5 mg/L free residual chlorine after 30 minutes contact, and no less than 0.2 mg/L at the point of delivery. UNHCR's targets add a footnote of 1 mg/L at the collection point during an outbreak.

Why is stored water the weak point?

Because chlorine decays in the container. A study in South Sudan refugee camps found 40 to 58 percent of households drawing from chlorinated sources had no detectable residual in stored water.

How much soap should be distributed?

UNHCR states at least 450 grams of soap per person per month, of which 250 grams is for personal hygiene and 200 grams for laundry and other washing.