The Local Government Association (LGA), which represents more than 370 councils, said restaurateurs should “take responsibility” and offer tap water so children have an alternative to a sugary drink.
A survey by the LGA found that while people most people drink tap water at home far fewer do in restaurants, with a significant number feeling awkward about even asking for it.
The research also found many restaurants only offer tap water on request, despite a legal requirement that licensed premises provide it.
The LGA is calling on the Government to use its forthcoming childhood obesity strategy as an opportunity to encourage restaurateurs to take responsibility and offer parents and children the choice of tap water.
But one leading Leeds restaurateur said he already made sure tap water was freely and openly available and suggested parents should be able to take responsibility and ask for it themselves.
Gip Dammone, who runs Salvo’s Italian restaurant in Leeds, said: “It’s very easy to say can I have some tap water.
“Don’t be shy about it, don’t feel it’s something weird as if it’s something demeaning. We shouldn’t feel diminished if we’re not throwing money at everything.”
James Banks, who owns the award-winning Black Swan at Oldstead in North Yorkshire, said he supported restaurants making tap water easily available and added that he always made clear free filtered tap water was available to diners.
“I’m a typical, tight Yorkshireman who hates paying when you don’t have to and I would always make sure tap water is offered first ahead of mineral water to try to pre-empt anyone feeling awkward about it,” he said.
The LGA survey found eight out of 10 people usually drink tap water at home, but only a third do so when eating out at restaurants.
The same survey found that 15 per cent of those who usually drink tap water at home never think of asking for water in cafes or restaurants, while 13 per cent said it made them feel awkward.
Child obesity has become an increasingly urgent problem nationwide and regional figures released earlier this year showed nearly 20,000 children in Yorkshire and the Humber leave primary school overweight or obese.
The LGA has previously called for tap water to be made more freely available in schools, nurseries and children’s centres.
Izzi Seccombe, the LGA’s community wellbeing spokeswoman, said: “While most restaurants will happily provide a glass of tap water on request, we’re saying it shouldn’t be something you have to ask for.
“Some people may be too embarrassed or find it awkward to ask for tap water. Others may simply forget it’s an option.
“For children it’s an alternative to a sugary drink, while for adults it might dissuade them from ordering another alcoholic drink.”
Russ Ladwa, chairman of the British Dental Association’s health and science committee, said: “Beverages, including soft drinks, fruit juices and alcohol, are now the number one source of dietary sugars for all age groups in Britain.
“Offering tap water is a simple way the restaurant industry can play its part on turning the tide on tooth decay and obesity. Diners deserve a choice, but shouldn’t feel they have to ask for the one option that doesn’t come bundled with sugars, acids or calories.”