This shout echoes out in all towns and many villages across Africa's most populous country and the continent's largest oil producer.
These small cellophane water bags - unlike tap water - are readily available, and come chilled.
Water experts say that they are anything but pure, but that means nothing to the millions of Nigerians who have no access to good, clean water.
Lagos is the unofficial headquarters of the "pure" water industry and has many fans.
|What we inherited a sector that was virtually comatose |
Lagos Water Corporation
"It is neatly presented and easily available. In Lagos it is much more dangerous to take tap water than pure water," an enthusiastic customer explains.
Detractors complain, however, that pure water producers - who are meant to drill boreholes and purify the water privately - pilfer the water from state water pipes.
Until five years ago, these pipes reached woefully few areas of the city.
But the chief executive officer of the Lagos Water Corporation, Olumuyiwa Coker, says things are slowly improving since he's come to the helm of the state authority.
"Right now we have 50% coverage. We expect that in the next 10 years that should increase to between 70%-80%," he says.
"What we inherited four of five years ago was really a sector that was virtually comatose."
Lagos's first potable water supply plant was established at Iju, more than 80 years ago. Today the city's population - an estimated 12m - has far outstripped the production capacity of the Iju Waterworks.
So with only half the population having potable water - and that's when the pumps are working - have state authorities simply being ignoring the problem?
It appears not: a much bigger second plant to boost supply has been built at Adiyan, reputed to be the biggest in Africa.
"This plant was commissioned in 1991 to produce 70m gallons per day," Production Manager Mustapha Olajide Agiri says.
"Technically there is no problem. Our major constraint is with the power supply, as on average we only get about 16 hours a day."
Indeed, at both Iju and Adiyan waterworks, it is the epileptic electricity supply from the national energy company that is hampering production and bumping up costs.
They have to resort to diesel generators which, officials say, makes the production very expensive.
As far as the public is concerned, however, the main water problem, apart from insufficiency, is its quality.
But the production engineer at Iju Waterworks is adamant that his plant meets international standards.
|It has good stability and a pH of 7.0, which is one of the best in the world |
"The quality of the water we pump is comparable even with Europe," Engr Ehunmi says.
"It has good stability and a pH of 7.0, which is one of the best in the world."
He explains that the colouring found in tap water in many areas is a result of contamination in the pipes laid by consumers to take the water into their premises.
The UN's target to halve the number of people without safe drinking water by 2015 is something the Lagos Water Corporation is committed to, Mr Coker says.
"Essentially what it entails is increasing our infrastructure to probably twice the size it is now by 2015," he says.
But to do this, the corporation needs resources, which is unlikely to be forthcoming from the state government, he says.
As in so many other sectors, it is the availability of funds that will eventually decide whether or not the people of Lagos beat poverty and get good, safe drinking water or 10 years' time.
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