As for the claim that New York’s water quality is what makes our pizza and bagels better than everyone else’s, that’s been thoroughly debunked --- and in fact, New York’s baked goods may succeed in spite of New York’s water, not because of it.
There are two main aspects of water quality that affect the taste and texture of dough, according to Tom Lehman, formerly the director of bakery assistance at the American Institute of Baking, who has written widely about the chemistry of baking and goes by the moniker “the dough doctor” (though he is not a real doctor).
The first factor is water hardness, a measure of the amount of dissolved minerals, primarily calcium and magnesium, that the water contains. Calcium strengthens the gluten in the dough, making hard water better for baking. New York water is soft, however, which can lead to gooey, “weak” dough.
The second factor is the ph level, or acidity of the water. New York water is about 7.2 on the ph scale, making it slightly alkaline (7 is neutral). According to Lehman, that is enough to slow down the activity of the yeast, which prefers an acidic environment to grow. Good bakers would adapt to these conditions, Lehman says, using more yeast and less water to compensate. “When people are making pizza, bagels, breads they learn to work around it. It’s recognizing what you're up against and coping with it,” he says.