Families in Brazil's dry north-east build their own rainwater tanks
Rural households in Brazil's semi-arid north-east build 16,000-litre tanks beside their homes to store roof rainwater, cutting long walks for water during the dry months.
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The small thing
A family and a local mason spend about five days building a cylindrical cement tank next to the house and connecting it to the roof with gutters.
The problem
Brazil's semi-arid north-east receives roughly 300–800 mm of rain a year, falling in a short season, with 8 to 11 dry months (IPS). Before cisterns, women often walked six to eight kilometres carrying 20 litres of water on their heads, and families relied on tanker trucks or distant reservoirs.
Why the families of Brazil's semi-arid north-east started
The ASA network of civil-society groups, created in 1999, promoted the idea of 'living with' the semi-arid climate rather than fighting drought. IPS reports that ASA saw household rainwater storage as a way to improve quality of life and to involve families directly rather than offering handouts.
What they did
Communities choose priority families – for example those with many children, older relatives or a woman as head of household. Each family helps build a 16,000-litre cement tank beside the house, working with a mason, and attends training on collecting and keeping water clean (IPS, 2005 and 2010). Local NGOs in the ASA network map families and give technical support, with federal funding since 2003 (Brasil de Fato).
In 2005 IPS met Antonio Xavier de Souza, a member of the Pipipan Indigenous people in Floresta, Pernambuco, whose family tank had been in use for three years. In 2024 Brasil de Fato reported on farmer Glauciane Magalhães in rural Senador Pompeu, Ceará, whose family had bought water from tanker trucks before receiving a cistern.
What changed
According to Brasil de Fato (2024), more than one million cisterns have been built across 1,262 semi-arid municipalities, averaging around 50,000 a year over two decades. IPS reported in 2010 that over 273,000 people had been trained in water management. Independent measurement of health or time savings at household level is not given in these sources.
What they learned
ASA's Naidison Baptista told IPS that because families build the tanks themselves, they are achieving something rather than receiving a handout. Antonio Xavier de Souza's experience showed that one tank may not last a very dry year, so other sources are still needed.
“By building the tank themselves, the families are achieving something, they're not receiving a handout”Rural families of Brazil's semi-arid region, with the Articulação Semiárido Brasileiro (ASA) network, as quoted by Inter Press Service
Copy this idea
Practical guidance written by our editors from the sources below. Adapt it to your place, and check local rules and safety first.
- Problem addressed
- Unreliable drinking water in places with a short rainy season.
- What to do
- Roof rainwater harvesting into a covered household tank.
- Materials and resources
- Gutters and downpipes, a first-flush diverter, a sealed tank (cement, ferrocement or plastic), a tap or hand pump.
- Approximate cost
- Low
- Skills
- Basic masonry or plumbing; training in water hygiene.
- Time
- Days to build; ongoing maintenance.
- People needed
- One household with help from a skilled builder.
- Difficulty
- Moderate
- Risks and limitations
- Stored water must be kept covered and clean; treat it for drinking where advised. Tanks need child-safe lids and mosquito-proofing. Check local building rules.
- How to adapt it
- In wetter or urban areas, a smaller water butt for gardens is a simple start.
- Lessons learned
- Size the tank to roof area and rainfall, ration through the dry season, and keep a back-up source.
Why it matters
A single rainwater tank will not end drought. But storing the rain that falls on a family's own roof gives a reliable store of drinking water close to home, reduces dependence on tanker trucks and long walks, and can be built with local skills.
Policy connection
International commitments this kind of action contributes to. Listing a framework does not mean the person or group was working towards it.
- SDG 6.1 and 6.4: Safe and affordable drinking water for all; increase water-use efficiency and address scarcity.
- Paris Agreement, Article 7: Enhancing adaptive capacity, strengthening resilience and reducing vulnerability to climate change.
What didn't work
In the drier year of 2005 Antonio's tank ran out in April, compared with September the year before, and his family had to haul water by ox cart (IPS). Small roofs cannot fill a tank. A programme technical adviser called the original one-million goal over-ambitious. Federal funding fell from about 150,000 cisterns in 2014 to about 3,000 in 2022 before being resumed (Brasil de Fato).
Editor's note
Cistern building slowed sharply after 2014 (about 3,000 units in 2022, per Brasil de Fato) and was resumed with federal funding in 2023–2024.
Sources: how do we know?
Evidence level: Documented. Supported by reliable published sources such as UN agencies, award bodies and reputable journalism. Not yet independently re-verified by our editors. What the person says and what independent sources establish are attributed separately in the text.
- reputable journalism
BRAZIL: Rainwater Tanks Represent Health and Hope for 100,000 Families — Mario Osava, Inter Press Service, 12 September 2005Supports: Antonio Xavier de Souza (Pipipan, Floresta); 16,000-litre tanks; families supply labour and training; tank running out in dry year; roof size limits; goal judged over-ambitious. - reputable journalism
Brazilian Communities Find Ways to Live in Semiarid Environment — Fabiana Frayssinet, Inter Press Service, 26 October 2010Supports: Rainfall and dry months; family selection criteria; five-day build with a mason; women walking 6–8 km; 273,124 people trained; Baptista quotes. - reputable journalism
Governo Lula volta a distribuir cisternas para o semiárido — Rodolfo Rodrigo, Brasil de Fato, 11 April 2024Supports: ASA created 1999; federal funding since 2003; over 1 million cisterns in 1,262 municipalities; peak ~150,000 (2014) and low ~3,000 (2022); resumption; Glauciane Magalhães.