The city of Rochester, New York, saw its fortunes rise with the 1823 completion of the Genesee River Aqueduct of the Erie Canal. Rochester was called the “Aqueduct City” by at least 1866.
 
Other modes of transportation lessened the importance of the Erie Canal, and the “Aqueduct City” nickname is mostly historical today.
 
   
Wikipedia: Rochester, New York
Rochester (/ˈrɒtʃɨstər/ or /ˈrɒˌtʃɛstər/) is a city and the county seat of Monroe County, bordering the southern shore of Lake Ontario in the western portion of the U.S. state of New York.
 
Rochester’s city population according to the 2010 census is approximately 210,565, making it New York’s third most populous city after New York City and Buffalo. It is at the center of a larger metropolitan area which encompasses and extends beyond Monroe County and includes Genesee County, Livingston County, Ontario County, Orleans County and Wayne County. This area, which is part of the Western New York region, had a population of 1,079,671 people at the time of the 2010 Census. As of July 1, 2012 estimates indicated that this population rose to 1,082,284.
 
Rochester was one of America’s first “boomtowns” and rose to prominence initially as the site of many flour mills located on the Genesee River, then as a major manufacturing hub.
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By 1821, Rochesterville was the seat of Monroe County. In 1823, Rochesterville consisted of 1,012 acres (4 km2) and 2,500 residents, and the Village of Rochesterville became known as Rochester. Also in 1823, the Erie Canal aqueduct over the Genesee River was completed, and the Erie Canal east to the Hudson River was opened. (In the early 20th century, after the advent of railroads, the presence of the canal in the center city was an obstacle; it was re-routed south of Rochester.) By 1830, Rochester’s population was 9,200 and in 1834, it was re-chartered as a city.
 
The Erie Canal
The Genesee River Aqueduct
Historical tablet for the Rochester Aqueduct Building of the first aqueduct to carry the Erie Canal over the Genesee River at Rochester was started in the fall of 1821, with completion in September 1823. Built of Red Medina sandstone with a coping of Onondaga Limestone, it was 802 feet long and 17 feet wide and had 11 arches. This first aqueduct had a problem with leakage, and construction began in 1836 on a new aqueduct a short distance to the south. This second aqueduct, made of Onondaga Limestone, was placed in service in 1842. It crosses the river on seven arches of fifty two feet span each, resting on six piers and two abutments, each ten feet thick. The arched portion extends 444 feet, and the whole length including wing-walls is 800 feet. The original trunk was 65 feet, with an overall width of 70 feet. This is the structure that exists today as the base of the Broad Street Bridge.
 
9 April 1866, Cleveland (OH) Daily Plain Dealer, “Geographical Nicknames,” pg. 2, col. 5:
Nicknames of some cities and towns:
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Rochester, Aqueduct City; ...
 
Google Books
August 1866, American Agriculturist, pg. 295, col. 2:
... Rochester, Aqueduct city; ...
 
Google Books
The Little Giant Cyclopedia and Treasury of Ready Reference:
1,000,001 Figures and Facts
By K. L. Armstrong
Boston, MA: Geo. M. Smith
1889
Pg. 140 (Nicknames of Cities):
... Rochester, Aqueduct City; ...
 
10 August 1895, New York (NY) Times, pg. 7, col. 2:
Some American Towns.
From The Ram’s Horn.
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Rochester is the Aqueduct City, from its bountiful water supply.
 
Google Books
Commercial Geography
By Walter Herbert Olin
Topeka, KS: Crane & Company
1902
Pg. 221:
Rochester, N. Y.—Flower City; Aqueduct City.
   
Google Books
Names & Nicknames of Places & Things
By Laurence Urdang
Boston, MA: G.K. Hall
1987
Pg. 314:
Rochester, New York: Aqueduct City; ...