Jamie Oliver's sugar tax raises £50,000
Over 130 restaurants including Leon, Abokado and the Jamie's Italian chain have introduced the levy following a campaign by the celebrity chef and food charity Sustain.
It is hoped that access to free drinking water will discourage young people from buying unhealthy sugary drinks.
But Sustain said the amount raised could reach £1bn if the Government imposes a nationwide tax.
The news comes amid reports that David Cameron has rejected proposals for a sugar tax of 20 per cent in the Government's upcoming Childhood Obesity Strategy.
The Prime Minister will instead use the threat of the levy to pressure companies in to reformulating their products to reduce sugar content, according to The Telegraph.
But Ben Reynolds, deputy co-ordinator of Sustain, said the public wanted to see tougher action on sugar.
“We’re showing Government that this tax for good is really working, and is really going to make a difference for children across the country," he said.
"But a handful of restaurants doing this is no substitute for Government action. The public support this and Mr Cameron has said this option is definitely on the menu, now let’s put it into law.”
In November a report by the Government Health Select Committee recommended introducing a 10p sugar tax and stricter controls on soft drinks promotions available in restaurants and pubs.
A Department of Health spokesman said: "Our childhood obesity strategy will look at everything, including sugar, that contributes to a child becoming overweight and obese. It will also set out what more can be done by all sides."
