Where do you report a restaurant that wont give you tap water if you ask for it?

If you go back bring your own water. The sign saying only food and drink purchased here can be consumed here is not legally enforcable either.

Freedom's just another word for nothin' left to lose,

And nothin' ain't worth nothin' but it's free,

Feelin' good was easy, Lord, when Bobby sang the blues,

And buddy, that was good enough for me,

Good enough for me and my Bobby McGee.

https://www.youtube.com/watch?v=5Cg-j0X09Ag

In a company I used to work in the water was deemed safe to drink. But when you ran the tap and put it in a glass, the water was cloudy - like watered milk. We didnt drink it, we didnt even use it for tea. There is no way we could give a glass of that water to a client. Just because an areas water supply is deemed ok to drink by authorities doesnt mean its quality either. Treated Tap water can sometimes taste different to how it should aswell. There are several areas all over the country where water is deemed safe yet people living in those areas use bottled water.

In a restaurant setting tap water can only be served if it tastes good and actually is clear. If I owned a restaurant Im not sure I would be happy to serve tap water - I could very possibly be leaving myself open to litigation should a customer become ill from that water. The quality of tap water can change very quickly.

Also I think if you go out for a meal you have to be prepared to pay. Expecting or demanding tap water which may be of dubious quality is unreasonable.

Perfectly fine to drink apparently. We didnt drink it though because it looked and tasted awful. Would you serve a glass of cloudy water to a customer in a restaurant - no you wouldnt! Would you drink a glass of cloudy water if it was served to you in a restaurant - no you wouldnt!

I dont agree with you that the quality of water in Dublin is great and safe to drink all the time.

my first question here would be if the water is unsafe to drink, how can they use it for cooking/washing /cleaning?

i'd be declining to eat in that establishment in future.

a restaurant is a business. just because you determined that tap water should be free as its a basic human need, it doesn't impede the fact that the waitor has to take the order, go to the kitchen, take a glass, fill it with water (possibly multiple times), then when you leave, the have to return glass to kitchen, clean and dry. and this action needs to be free.

@OP would you have the same complaint if the restaurant charged for the tap water with the above in mind?

But ever serving "Tap water" would be a cost to the restaurant. Who do you think pays the server to get the water for you, and clean the Glass/Cup before and afterwards.