SHOP TALK : Taking the Waters, Supermarket-Style : When normal tap water won’t suffice, you may want to see what is available to drink at the local grocery store.

Guess how many brands of bottled drinking water that Camarillo’s Hughes Market carried last week? Sixteen, in the 1.5-liter size.

We find that pretty amazing. We always assumed that all bottled water was the same, so we never bothered looking past the price tag. But when we saw how many varieties were available, it got us to wondering:

How does Arrowhead mountain spring water differ from Sahara mountain spring water or Niagara drinking water? How is Vittel’s French mineral water different from Evian’s French natural spring water? And where does Canadian glacial water fit in?

First of all, it’s nice to know that water must pass stringent regulations to be bottled and sold in the United States. Federal regulations are imposed by the Food and Drug Administration, and each state has its own set of constraints. Lisa Prats, vice president of the International Bottled Water Assn., said California has some of the most comprehensive state regulations.

The IBWA itself serves as a regulatory body. Prats said 85% of all bottled water sold in the United States is produced and distributed by a company belonging to the association. As a member of the IBWA, a bottler is subject to annual unannounced inspections.

Any difference between one brand and another, Prats said, comes from the source and processing of the water. And that’s where things get a little confusing.

Bottled water is generally mineral water, spring water, artesian water, well water, purified water or distilled water.

“Mineral water is derived from deep underground aquifers,” Prats said. “Spring water is from deep underground aquifers that spring up to the surface. Well water comes from deep underground aquifers, where a well is drilled to tap into it. And artesian well water is water that emerges on its own, not to the surface of the Earth, but past the natural water table.”

Purified water is distilled, deionized and stripped of all minerals. Bottlers then return trace elements, such as magnesium and calcium, to add flavor. Distilled water, which is often used for purposes other than drinking, is purified, with no minerals added back.

“We all have personal preferences in the wine we drink and the soft drinks we drink. Bottled water is a beverage too,” Prats said. “A lot depends on personal taste.”

But let’s not forget cost.

Last week, we visited a local Vons and Ralphs, in addition to Hughes, and found a tremendous price range. For simplicity, we focused on the 1.5-liter and gallon containers.

At Vons, the price of a 1.5-liter bottle ranged from 55 cents for Arrowhead mountain spring water to $1.62 for Evian natural spring water. At Ralphs, the cheapest was Sahara natural mountain spring water at 62 cents, the most expensive, Evian, at $1.69. And at Hughes, the least expensive was Rocky Mountain drinking water at 59 cents, and the most expensive, yes, Evian, at $1.59.

As for the gallon jugs, at Vons, the range was 79 cents for generic purified water to $1.14 for Arrowhead mountain spring water. At Ralphs, it was 69 cents (down from 79 cents) for the generic brand to $1.24 for Oasis drinking water. And at Hughes, the generic brand was the cheapest at 49 cents, Sparkletts the most expensive at 99 cents.

Just to confuse you a little further, there’s a shop in Ventura called the Water Store that is equipped with its own filtration system. It offers an extensive list of buying options, but to keep things simple, a 1.5-liter container of purified drinking water is $1.25, a gallon is just 45 cents.

Of course, you don’t even have to leave your home to get fresh water.

Locally, home-delivered Arrowhead mountain spring water is priced at $6.25 for a three-gallon bottle, $8.25 for five gallons. Sparkletts purified water, with or without minerals, is $5.95 for three gallons, $8.50 for five. Hinckley & Schmitt drinking water, distilled water or fluorinated water is $7.30 for five gallons, and its mountain spring water is $7.90 for five gallons. And Matilija Water Co. drinking water is $5.10 (three gallons), $7.35 (five gallons). Its pure and fluoridated water is $7.46 (five gallons).

Of course, for home delivery, you’ll pay a monthly fee for dispenser rental. The basic dispenser is $2.25 for Arrowhead, $3.75 for Sparkletts, $2.50 for Hinckley & Schmitt and $2.50 for Matilija.

For total confusion, let’s toss in another option--filtering your own tap water. There are a number of companies in the county that will install reverse osmosis systems for that purpose.

Some sample monthly fees: Culligan Drinking Water, $13.75 to $16.50; Pacific Water Conditioning, $16.50, and Rayne Water Systems, $14.95.

Or you can purchase your own filtering systems at grocery stores. The common Brita brand runs about $20 at the three stores we shopped at, with a 12-pack of replacement filters going for $7 to $8.

It’s enough to make you drink.