East Side
A very interesting hypothesis on why the east side of cities are often poorer (which I can’t say I’d notice, but I’ll take their word for it):
The reason for this is that in much of the northern hemisphere, the prevailing winds are westerlies – blowing from west to east. The massive, unchecked pollution from these early industries would therefore drift eastward, making the air quality much lower in the east end of cities, lowering the desirability (and price) of the housing. Middle classes preferred the cleaner west ends.

Hi, I'm 
I can’t speak for everywhere, but in Austin and L.A. (and for that matter, Orange County as well) it’s true.
I always assumed it had more to do with proximity to the beach in Southern California…but the pattern holds true in Austin with no ocean in sight.
Perhaps They are thinking of Europe?
The east side of Boston, NY, Philadelphia, Chicago and Miami are alll pretty posh (and that’s just off the top of my head)
East Coast cities tended to be ports, so they naturally expanded westward and so the wealthy suburbs are to the west, north or south someplace in the Atlantic Ocean.
In the only non-coastal city I’m familiar with, Dallas, the split is north/south.
Enough bloviaitng. It’s an interesting theory, probably correct in older European cities.
Thanks for finding another interesting blog for me to read and Happy New Year
Hmm, wonder: (1) if most cities planned their industrial parts to be on their eastern extremes then, but things got out of hand; (2) why lower classes didn’t just move further out west. Interesting anyhow.
This is an interesting hypothesis. It would be a good project to research and collect data on whether housing correlates with pollution.
@clweinfeld
Or maybe it’s because in this country we reached the east side first, built a city and then as people made some money, built their new posh homes to the east as the new poor folk took their old homes.
@Aalan In Manhattan the east side is posh, but New York doesn’t end at the East River. Queens/Brooklyn isn’t as posh.
New York is also a bit different because of the rivers. In Manhattan there wasn’t enough east or west, so the rich moved north. The cities of Queens and Brooklyn didn’t have a west, so they went east. Most of the posh still stayed in Manhattan, except when they wanted more posh and had to go east and jump over Brooklyn/Queens and make Long Island posh.
Sticking with this rich tide moving west, but with the eastern cities seeming to contradict the premise: There is only so much west until you hit other cities, so after time, some of the posh had to go east. This is what happened to Brooklyn in the past twenty years.
(I think I’ve now used my allotment of “posh” for the next two years.)