CHATEAU TAP-WATER

The humorous expression chateau tap-water likens tap-water to a grand cru.

This expression refers to the use of the noun château in names of expensive wines of superior quality made at vineyard estates, especially in the Bordeaux region of France—as in Château Margaux, Château d’Yquem, Château Lafitte and Château Latour.
—Cf. also the humorous expression Château Plonk, which is used of wine, especially of cheap wine of inferior quality.

The earliest occurrences of the expression chateau tap-water that I have found are as follows, in chronological order:

1-: From the Burton Observer and Chronicle (Burton upon Trent, Staffordshire, England) of Thursday 7^th November 1974:

Package holidays have put wine into fashion
Not very long ago it was very rare to be able to go out for a meal and order a bottle of wine because very few restaurants had anything more than a glass of chateau tap water to offer to their clients. Those restaurants which did have wine to offer had such long and complex wine lists that only the chosen few seemed to be acquainted with the secrets they had to offer.
Now the situation has changed apparently overnight. The package holiday became popular and Britons sunning themselves on foreign beaches watched at first in amazement, as the locals downed mysterious foods washed down with large quantities of the local plonk. Human nature being what it is they soon decided to try some for themselves and discovered that wine was not something only to be enjoyed by the rich, and the wine drinking habit returned to Britain with them.

2-: From the Chelsea News (London, England) of Friday 6^th December 1974:

Wine lists, they are a changing . . .
IT wasn’t so very long ago that the number of restaurants offering wines was so small that if you happened to get caught in the provinces unexpectedly overnight and wanted a reasonable meal with a bottle of wine you would have been out of luck—as they say.
Customarily the only form of liquid refreshment in such establishments was a tepid glass of chateau tap water, or, if you were lucky, a slightly sticky glass of some revolting fruit squash.
And those gastronomic oases that did offer wine had wine lists of such Biblical length and mystic complexity that only the discerning cognoscenti were privy to their well-kept secrets.
Then, seemingly overnight, the situation changed. The package holiday came in with a bang (rather as it has, with a certain well-known group, gone out with a bang) and with it the realisation that wine was not just something for the rich minority.

A variant occurred in Maestro’s favorite dessert is plum tart, by Joyce Rosencrans, Post food editor, published in The Cincinnati Post (Cincinnati, Ohio, USA) of Wednesday 28^th August 2002:

Artichokes clash terribly with any wine, actually changing the wine’s flavor upon the palate. Artichokes even change the flavor of water, but they improve water, if not wine. Sip some Chateau Cincinnati tap water after your next artichoke leaf, base or heart. You’ll see that the water tastes slightly sweet, better somehow.

CHÂTEAU-LA-POMPE

The French expression Château-la-Pompe (i.e., Château-the-Pump) likens tap-water to a grand cru. This expression is composed of:
– the masculine noun château as used in names of expensive wines of superior quality made at vineyard estates;
– the feminine noun pompe in the sense of a mechanical device for raising water.

The earliest occurrences of the French expression Château-la-Pompe that I have found are as follows:

1-: From Jean-Jean (Paris: Librairie illustrée, 1886), by Albert Brasseur (1860-1932) and Frantz Jourdain (1847-1935)—in this passage, Jean-Jean, who has just been conscripted, is talking with Rivet, the cook at the barracks:

— Qu’est-ce que vous buvez aux repas ? demanda-t-il.
— Ah ! mon dieu, répondit Rivet, nous avons la cantine où l’on trouve la goutte et du petit vin de l’année prochaine. Mais, comme ordinaire, nous possédons le Château-la-Pompe qui coule à flots dans la cour de la caserne.
     translation:
— What do you drink at mealtimes? he asked.
— Ah! well, Rivet replied, we have the canteen, where you can find the eau-de-vie and next year’s small wine. But, as for our ordinary, we own the Château-the-Pump, which is flowing freely in the courtyard of the barracks.

2-: From the Gazette des Touristes et des Étrangers (Paris, France) of Sunday 1^st May 1887—Wallace Fountains are public drinking-fountains in Paris:

Savez-vous le nom que les petites gens ont donné au liquide des fontaines Wallace ?
Ils l’appellent du Château-la-Pompe.
     translation:
Do you know the name that the little people have given to the liquid of the Wallace fountains?
They call it Château-the-Pump.