ON FIRST appearances, it looks like your typical edgy inner city bar. Housed in an old industrial space, projections light up dimly lit corners as white clad waiters weave through the crowd.

However, there’s one big difference, this bar serves only one drop. It’s not beer, it’s not wine — it’s water. The menu includes groundwater, rain water, even the odd bit of dam water, but, when push comes to shove, it’s just water.

News.com.au got a special sneak peek into the H20 Bar, very probably Australia’s first ever pub that serves only water. Set deep within the bowels of Paddington Reservoir Gardens, which used to quench the thirst of Sydneysiders, leaning against one wall is a map of eastern Australia. Shorn of cities or borders all it shows is the veiny network of rivers carrying this continent’s share of the less than one per cent of the world’s water that it’s possible to drink.

As someone who struggles to tell their Shiraz from their Cab Sauv, I’m here to see if I can tell the difference between a Kiewa Valley High Alpine water and a Cooroy natural spring water.

SOMMELIER

At this point, it’s probably worth pointing out the H20 bar is not actually the moment Sydney’s bar scene finally disappeared so far up its own posterior that the city’s glitterati were willing to sit in an old water tank and order a liquid that pours freely from the tap.

Rather, the bar is a free art installation from renowned artist Janet Laurence who said the aim is to connect people with something all around them, vital to life yet often ignored.

“In Australia, we’re not really aware enough of the qualities of water and even though we’re a country stricken with drought, in somewhere like Sydney there is isn’t a lot of awareness of the fragility and politics of water.”

Part of the City of Sydney’s year round Art and About festival, Ms Laurence said H20:Water Bar fitted into her earlier works which throw a spotlight on the environment.

Art or not, anyone can wander into the pop up pub over the next two weeks, head to the bar, decked out in a apothecary aesthetic, and sample any of 20 drops from all over Australia served up in test tubes and beakers reminiscent of a high school science class.

As a sommelier pours a vintage, Ms Laurence tells me that the waters should all have different tastes due to their various origins or the rocks they have eased their way through, some over thousands of years.

Room temperature is best for tasting, as the flavour can be impaired if too cool.

Like wine, can you match waters with food? “Because it’s so pure I’d pair a Cape Grim rain water with very pure food like veal but you have to be careful because foods can detract from the subtleties of water,” she says.

RAIN WATER OR DAM?

First up is a comparison between, if you like, two ends of the spectrum. The aforementioned Cape Grim rain water and plain old Sydney dam water.

It’s probably a bit of an unfair comparison. Despite its municipal name, Sydney water is pretty classy stuff, much of having fallen on the Blue Mountains and then collected in the dam at Warragamba, which means ‘water over rocks’ in the local Aboriginal language.

But like any tap water, it’s treated and chlorine and fluoride has been added. As I taste this water every day, it’s a struggle to think of it as not a neutral liquid but something with a flavour. While by no means the most pungent of the tap waters on the menu, if I really concentrate I eke out that Sydney water has a metallic aftertaste with a chalkiness coming through from the high calcium levels. See, that wasn’t too hard. I can do this.

Next up, it’s Cape Grim rain water, the champagne of H2O. From north west Tasmania, officially the cleanest corner of Australia, it is harvested only when the wind is blowing in from Antarctica, said Ms Laurence, to avoid pollution from the mainland.

And, look, it’s quite something. With only trace elements of minerals, plus the merest hint of magnesium, the earthiness found in almost every other water is almost entirely non-existent replaced with an palate that could almost be described as sweet and floral with a touch of butteriness in the mouth.

HOW TO PICK YOUR PERFECT WATER

If you like sauvignon blanc, try …

COOROY NATURAL WATER, QLD

High in bicarbonates and sulfates and filtered through magnetite rock, this lively drop hits the back of the throat with the earthy freshness of a meadow after the rains.

If you like vodka, try ...

BARGO NEPEAN DAM WATER, NSW

The tap water of many of the residents of the NSW Southern Highlands, Bargo is by far the most pungent with a chlorine waft and a taste with all the subtlety of the local swimming pool after the metal scaffolding on the building site next door has collapsed into the deep end.

If you like pale ale, try ...

MACEDON RANGES GROUND WATER, VIC

Another lively number, this water from country Victoria has your daily fill of silica which is great for the skin. A subtle taste but with a distinct sandiness.

If you like Shiraz, try …

BELOKA GROUNDWATER, NSW

From the Snowy Mountains, this is the red wine of waters. Thick and full in the mouth with a powerful aroma and an earthy taste with a sodium kick.

If you like alcopops, try …

HARTZ GROUNDWATER, TAS

Full to the brim with bicarb and calcium it’s the sodium in this water which really makes its presence felt with one of the strongest, and most intriguing palates of the pack. Like digging into the liquid equivalent of a chocolate covered pretzel.

NO HANGOVER

I bump into a fellow drinker and like me she’s not holding back, downing H20 with gay abandon. “It’s easy to think water is always going to come out of the tap but I grew up in the country where we had to not use too much water when cleaning you teeth and have quick showers.

“I think its great focusing on such a precious commodity and not just tasting it but appreciating it,” she said knocking back another beaker of Illawarra Dam.

By this time, the well hydrated crowd has had drained the former reservoir dry. And as well as looking more refreshed when you finish the night, another good thing about overdoing it at a water bar is you don’t have to worry about having a hangover the next day. Mind you, I was crossing my legs on the bus all the way home.

The drops at the H2O:Water Bar can be tried from 5-9pm on Thursdays and weekends from Saturday 13 February to Sunday 28 February 2016 at Paddington Reservoir Gardens, Oxford St, Paddington, Sydney.