There are few questions that have plagued human existence for centuries: What is the meaning of life? What happens to us after we die? How come baby animals are so darn cute? Then, there is maybe the most hotly debated question of them all: Does New York City tap water really make the city's bagels and pizza taste better?
At times, emotion and bias have co-opted the question. But according to science, the answer is a definitive... yeah, kind of. While the city's water is certainly unique and has defining qualities, the impact it has on the actual taste and texture of bagel and pizza dough may be more minimal. In fact, the production techniques are likely what makes these New York specialties taste better.
First, the water: With the largest unfiltered water supply system in the U.S., New York City tap water comes from the southeastern part of the state, from what is called the "NYC watershed." While there are three distinct areas it can come from, 90% of the water the city (and surrounding areas) consumes comes from the Catskill and Delaware Watersheds. Mostly collected from precipitation (rain and snowfall), the state of New York calls the water from the NYC watershed the "Champagne" of drinking water.
Then, of course, there is the water's long journey from the Catskills to the city's 9 million residents. It travels through a century-old system of pipes, tunnels, and streams to get from the mountains to one's mouth (or in this case, a pizza crust). According to The New York Times, that system is in serious need of repairs. The water takes anywhere from 12 weeks to a year to travel from the watershed to the city. Before arriving however, it lands at Hillview Reservoir (what The Times calls a 900 million-gallon bathtub) where the water is treated with a variety of chemicals —like chlorine, phosphoric acid, and sodium hydroxide —to disinfect and raise pH levels. From there, it enters the city and passes through a 6,800-mile-long network of iron and steel pipes (while the city has tried to replace all the lead pipes, it concedes that it's likely a few have been missed especially in old homes and buildings).
Along the way, the water can pick up a variety of minerals, elements, and components, not to mention the added minerals from Hillview and the natural deposits from the Catskills. This could include sulfate, radium, thorium, radon, fluorine, magnesium, lead, bromine, calcium, chlorine, bromate, and chloramines.
Every city's water differs slightly, depending on where the water comes from. New York water is considered to be "soft," meaning it has low concentrations of calcium and magnesium due to the makeup of the water that flows into the Catskills and Delaware Watershed. According to the American Chemical Society, the only American city with "softer" water is Boston. This makes a difference on several levels. For one, it's easier to create lather and suds with soft water. Soft water tastes slightly different than hard water, perhaps even saltier due to the increase in sodium ions. Beyond the taste though (and most importantly for our pizza and bagels) the difference in water also has an effect on the gluten in dough. The presence of calcium and magnesium in hard water strengthens the gluten in the dough, making the finished product tougher and stronger. With very soft water, the dough tends to get soft and sticky. As Smithsonian Magazine puts it, New York City tap water is sort of the "Goldilocks" of water when it comes to dough-making.
While this scientific proof will give many of the city's residents another reason to brag, the American Chemical Society makes it clear that this isn't the only reason —nor, likely, the main one —that the city's bagels are so good. The production process, most importantly the proofing of yeast and the boiling of the bagels prior to baking them, is what better defines the texture and taste of signature New York bagels. As for pizza, there's a reasonable theory that the people who make pizza in New York are just really good at making it due to decades of practice (and a knowledge of how important fermentation is in bread making).
So, yes, New York City water is unique and does contain properties that likely make it more conducive to better dough for bagels and pizza. That isn't to say that one can't make quality dough-based products outside of the city —after all, one can artificially make water softer, and a bagel chain that stretches from Florida to California and backed by Larry King is doing this and using it as a selling point. But come on, Florida bagels? Let's just say no one is writing songs about those.
