ABSTRACT
New Orleans under American administration saw its population double roughly every 10 to 20 years and its urban footprint expand upriver and downriver along the natural levee of the Mississippi River. From 1788 to the early 1900s, New Orleans expanded in a manner that was planned at the intrasubdivision scale but unplanned at the citywide scale. The appeal to pedestrians of minimal walking distances encouraged new developments to occur quite literally across the street from existing ones. The ad hoc "rules" driving 19th-century urban expansion encountered revolutionary new circumstances in the 20th century. Electrified streetcar lines and, later, automobiles undercut the historical need to develop adjacently to extant subdivisions. Modern water treatment, sewerage, electrification, telephony, steel-frame high rises, and other technological breakthroughs fostered the outward movement of residential land use and the transformation of the inner city to commercial use.
