Joel A. Tarr explores the role of technology in creating the “sinews” of the city, such as roads, water and sewer lines, power and communication systems and transit networks. Tarr examines the development of the modern city through advancements in technology, infrastructure and public works.
Between 1790-1870, there was little geographical separation between work and residence for most inhabitants within the city, increasing the need for several public works. The provisioning of water supplies was a major problem for growing cities as the population density increased. The uneven distribution of water systems throughout the city resulted in human wastes being stored in cesspools or cellars and the introduction of the water closet increased the dangers associated with the overflow of wastewater. The fragmented, decentralized system was eventually overhauled by civil engineers who made use of the current techniques but also had to invent a few along the way.
Advancements in transportation enabled a broader distribution of inhabitants inside and outside the city from 1870-1920. Tarr argues that new transportation systems, such as the electric street car, triggered both “deconcentration and concentration” trends, permitting affluent residents to separate their urban jobs from their suburban homes while limiting working class people to jobs closer to their houses. Better transportation introduced new consumer venues such as the department store and also opened up real estate markets that may have been perceived as somewhat inaccessible.
One of the most technologically influential factors in the development and spread of the city, according to Tarr, was the wide adoption of the automobile from 1920-2000. Vehicle ownership went from one car per 201 people to one car per 5.3 people from 1910 to 1930. Aside from the obvious value in person transportation, state and federal revenues were generated from gasoline sales which lead to new road networks on the local and national level.
Tarr’s division of city progression into three stages (the walking city, the network city and the automobile city) shows defined yet overlapping eras of technological innovation. His chapter illustrates the connection between innovation and expansion but more time could have been spent addressing the negative aspects associated with rapid urban development.