Water Storage for the Sudan Refugee Response: Tank Options, Sizing and Supply Routes

Tony Miller

Oct 2

8 min read

Size water storage from the Sphere planning range of 7.5 to 15 litres per person per day: a site of 10,000 people needs 75 to 150 cubic metres of supply every day. That is roughly one 95 m³ Oxfam steel tank at the low end and two at the high end, before any buffer for pump or trucking failure.

Why does the Sudan response put so much pressure on water storage?

Because the caseload is large, still growing, and arriving in places with no standing water infrastructure. UNHCR's 2026 regional plan covers 4.3 million Sudanese refugees across seven countries, expects roughly 470,000 further arrivals, and sets out to assist 5.9 million people against a US$1.6 billion appeal, according to UN News in February 2026. The same report notes that in eastern Chad more than 234,000 people were waiting for relocation in border conditions, and that funding cuts had already pushed assistance per refugee down in Egypt.

For a supplier in Juba the relevant geography is the South Sudan side. Renk in Upper Nile is where the 2024 cholera outbreak began, among returnees from Sudan, according to WHO AFRO. That outbreak reached nearly 100,000 suspected cases and more than 1,500 deaths across 55 counties, per WHO AFRO's October 2025 review. Transit centres and integration sites do not get to choose a calm year to plan storage.

Storage matters in this setting for a plain reason. A borehole or treatment unit that runs for a few hours a day only serves a camp if the water is held somewhere between pumping and collection. A tank turns a pump that fails on a Tuesday into a problem you notice on Thursday. It also gives you one controlled place to chlorinate, which is where most cholera-season water quality is won or lost.

What do the standards say a refugee site needs to store?

Start from Sphere, because donors and clusters audit against it. The Sphere WASH standards set 7.5 to 15 litres per person per day as the basic water need, with a water point no more than 500 metres from any dwelling and no more than 30 minutes of queueing. At household level they call for at least two clean, covered collection containers of 10 to 20 litres.

Those figures define two storage layers, and buyers who plan only one of them get surprised:

Communal storage at the source or treatment point, in tanks, which is what this guide sizes.
Household storage in jerrycans and buckets, which is where recontamination happens. A study of South Sudan refugee camps published in the Bulletin of the World Health Organization found that 40 to 58 per cent of households collecting from chlorinated tapstands had no detectable residual chlorine in their stored water, and that standard doses could not hold 0.2 mg/L for 24 hours. The authors recommended raising the initial target toward 1.0 mg/L.

The second point changes how you size the first. A communal tank that is too small forces short turnover and frequent re-dosing; one that is too large and rarely drawn down lets residual decay before collection. Sizing and dosing have to be decided together.

How big should the tanks be? A worked sizing example

Take a transit site of 10,000 people. The arithmetic is simple and worth doing on paper before you read any catalogue.

At 7.5 litres per person per day: 10,000 × 7.5 L = 75,000 L, or 75 m³ per day.
At 15 litres per person per day: 10,000 × 15 L = 150,000 L, or 150 m³ per day.

Oxfam's standard steel tanks come in four capacities: 11, 45, 70 and 95 m³, per the Oxfam Supply Centre, which describes them as deployed in humanitarian responses for 40 years. Matching those to the example:

75 m³ a day is covered by one 95 m³ tank, or one 70 m³ plus one 11 m³.
150 m³ a day needs two 95 m³ tanks, or one 95 m³ plus one 70 m³ if you accept a day's supply that is only just enough.

My view: size to at least one full day of demand at your planning figure, then add a second tank rather than a bigger one. Two tanks let you isolate, clean and re-line one while the other keeps the site supplied, and they give you a second chlorination point. A single 95 m³ tank is cheaper to buy and a single point of failure to run. Our companion guide, how much water storage a camp needs by population, works through the same sum for other site sizes and for different supply rates.

One caution on the numbers. The 15 L figure is a planning value, not a target you can assume you will hit in month one. New sites commonly start below it. Size for the figure you will be held to at the end of the first quarter, not the figure you can deliver on day three.

Which tank types suit a Sudan refugee site?

There are three realistic families, and the right choice depends on how long the site will exist and how fast you need water held.

Oxfam steel tanks (11 to 95 m³). Corrugated galvanised steel panels with a reinforced watertight liner, supplied as a kit and erected on site. The Oxfam Supply Centre lists steel liners in PVC or rubber, steel or UPVC roofs, plinths in 3.7 m or 8.3 m diameters, anchor bolt kits and scaffolding towers as separate components, and runs an installation training service. This is the right choice for a site expected to run for months or years: it is repairable, it can be dismantled and moved, and the liner can be replaced without scrapping the structure. The trade-off is erection time and a levelled, prepared base.

Butyl collapsible bladder tanks. Flexible tanks that arrive folded and are filled in place. They are the fastest way to get storage onto a new site, and the right call for the first weeks of a transit centre or where ground and labour for a steel tank do not exist yet. Their limit is durability under sun, handling and ground conditions, so treat them as bridging or short-duration storage and plan the steel replacement if the site stays open. We cover the choice in detail in our guide to Butyl tanks and water security in South Sudan.

Other storage you will see on site. Local plastic or polyethylene tanks and household containers are common wherever they can be bought, and they have a place for small clinics and distribution points. They do not scale to a communal tank farm for thousands of people, and quality varies. We do not supply them, so we will not rate them here beyond saying: inspect the material specification and confirm food-contact suitability before you buy.

The practical pattern we see work is a bladder first, steel second. A bladder gives you storage in days while the steel kit is moved, the base is prepared and the erection team is trained. When the steel tank is commissioned, the bladder is redeployed to the next site.

What goes wrong with tank installations at refugee sites?

Four recurring problems, all avoidable:

No base preparation. A steel tank needs a flat, compacted plinth, and a bladder needs cleared ground without sharp objects. In wet-season Upper Nile, a base prepared in the dry season is a washed-out base by July.
Chlorination as an afterthought. Plan the dosing point before the tank arrives. Decide tablet, sachet or bulk dosing for each tank before it is filled; the water chemistry matters more than the tank.
No spare liner or fittings. A liner is the consumable part of a steel tank. Order a spare with the kit, not after the first puncture.
Wrong site layout. Tank placement sets the 500 m collection distance. Put the tank where the tapstands can be gravity-fed or short-piped, not where the plot happened to be free.

What are the supply routes for tank kits into the Sudan response?

For the Sudan refugee response in South Sudan, the practical route is stock held in Juba and moved forward, not a shipment ordered from the manufacturer after the need appears. A tank kit ordered from the UK or elsewhere becomes a multi-week import with customs, corridor and inland transport stages before it reaches a field team. A kit already in a Juba warehouse is a dispatch.

That is what an in-country authorised distributor is for. Specialized Logistics Solutions is an authorised distributor for Oxfam tanks and Butyl products and holds stock in Juba, so steel kits and bladders can be quoted from in-country supply with delivery within South Sudan. In the 2024 to 2025 cholera response we ran the whole chain from procurement and customs clearance to Juba warehousing and last-mile delivery into Juba and Renk counties, which is the same chain a tank order into Upper Nile depends on. Our WASH products range lists the storage and treatment lines we supply, and our case studies show how those orders were delivered.

For other countries in the regional response, including Chad, Egypt and Ethiopia, planning is different: each has its own import regime and supplier base. We are not a freight forwarder, so we do not claim corridor routing for those destinations. If your programme spans borders, ask us what we can supply from Juba and what your logistics team should source locally.

How do you compare tank quotations?

Ask each supplier the same six questions and put the answers side by side:

Capacity and kit contents. Which size, which liner (PVC or rubber), which roof, and what is included: plinth, anchor bolts, fittings.
Authorised source. Is the supplier authorised by the manufacturer, and can they show it? Authorisation affects warranty and spares.
Delivered or ex-works. Where does the price stop? A cheaper ex-works quote can cost more once inland transport is added.
Spares and installation. Spare liner, installation guidance, training.
Lead time from stock. Days from a Juba warehouse is not the same as weeks from a port.
Documentation. Packing list, certificates, UNGM status if your procurement rules require it.

Frequently asked questions

How much water storage does a refugee site need?

Plan from the Sphere minimum of 7.5 to 15 litres per person per day. For 10,000 people that is 75 to 150 m³ of supply a day, and storage should hold at least one full day at your planning figure.

What sizes do Oxfam steel water tanks come in?

The Oxfam Supply Centre lists four standard capacities: 11, 45, 70 and 95 m³. Components such as liners, roofs and plinths are available separately.

Are Butyl bladder tanks or steel tanks better for a new camp?

Use a bladder for the first weeks, because it gives storage in days, and a steel tank for a site expected to last months or longer, because it is repairable and relocatable. The two work as a sequence, not as rivals.

Why does stored water lose chlorine in South Sudan camps?

Standard doses often fail to hold residual through storage and handling. A Bulletin of the WHO study of South Sudan refugee camps found 40 to 58 per cent of households had no detectable chlorine in stored water, and recommended raising the initial target toward 1.0 mg/L.

How many Sudanese refugees is the regional response supporting?

UNHCR's 2026 plan counts 4.3 million Sudanese refugees in seven countries, expects about 470,000 new arrivals and seeks US$1.6 billion to assist 5.9 million people.