Coca-Cola has come under fire in the UK after it emerged that the beverage giant's much-hyped Dasani brand is based on tap water.

Dasani, already the second-biggest bottled water in the US, has just been launched in Britain, backed by a £7 million ($13.0m; €10.5m) ad campaign from Lowe & Partners. It will shortly roll out in nineteen other European markets.

However, Coke's carefully crafted PR may be undermined by UK press stories revealing that -- unlike some rival water brands -- Dasani has not spent aeons filtering through mineral-laden rock, but is in fact based on tap water from Kent. It is then filtered, treated, bottled and sold as 'Pure, Still Water' to the public, which paid for the water to be purified in the first place by local utility Thames Water.

The story makes for a good headline. But despite the press hysteria, the fact that Dasani is not spring water has never been in doubt -- Coke has openly conceded this all along.

A pity, then, that journalists failed to visit the Dasani website, which freely admits the water's origin. "To create Dasani," it states, "Coca-Cola bottlers start with the local water supply, which is then filtered for purity using a state-of-the-art process called reverse osmosis."

However, Coke's claim that it purifies Dasani has not gone down well with Thames Water, which pointed out that its tap water already passes 99.92% of quality trials. "If the water regulator thought any more treatment was needed they would ask us to do so," the utility sniffed.

Onto which troubled waters Dasani's brand PR manager Judith Snyder hastily poured oil. "We would never say tap water isn't drinkable," she insisted. "It's just that Dasani is as pure as water can get. There are different levels of purity."

Data sourced from: BrandRepublic (UK); additional content by WARC staff