Editing History of Pittsburgh (section)

===Environment===
During the late 19th century, city leaders debated the responsibility and expense of creating a waterworks system and disposal of sewage. Downstream users complained about Pittsburgh's dumping of sewage into the Ohio River. Allegheny County cities did not stop discharging raw sewage into rivers until 1939. Pittsburgh's smoke pollution, seen in the 1890s as a sign of prosperity, was recognized as a problem in the [[Progressive Era]] and was cleared up in the 1930s–1940s. Steel plants deposited mountains of slag until 1972, especially in Nine Mile Run Valley.<ref>Joel Tarr, "The Metabolism of the Industrial City: The Case of Pittsburgh," ''Journal of Urban History'' 2002 28(5): 511–545</ref>

In November 1927, 28 people were killed and hundreds were wounded in an [[1927 Pittsburgh gas explosion|explosion]] of a gas tank.<ref>{{cite journal| last = Brotzman |first = W. S.  | title = Damaging Gas Explosion at Pittsburgh, PA. |journal = Monthly Weather Review  |volume=55  | issue = 11  | pages = 500  | publisher = [[National Weather Service|Weather Bureau]] |date=January 25, 1928 |url=http://docs.lib.noaa.gov/rescue/mwr/055/mwr-055-11-0500a.pdf  |access-date=January 17, 2008 |doi=10.1175/1520-0493(1927)55<500a:DGEAPP>2.0.CO;2|doi-access = free}}</ref>

To escape the soot of the city, many of the wealthy lived in the [[Shadyside, Pennsylvania|Shadyside]] and East End neighborhoods, a few miles east of downtown. [[Fifth Avenue (Pittsburgh)|Fifth Avenue]] was dubbed "Millionaire's Row" because of the many mansions lining the street.

On March 17 and 18, 1936, Pittsburgh suffered the worst flood in its history, with flood levels peaking at 46 feet. This catastrophe killed 69 victims, destroyed thousands of buildings, caused $3B (2006 dollars) in damages, and put more than 60,000 steelworkers out of work.<ref>Mildred Flaherty, ''The Great Saint Patrick's Day Flood,'' (The Local History Company, Pittsburgh, PA, 2004)</ref>