An urban center consists of more than just the brick and concrete of which it is built. The people who reside within are equally if not more important. By the eve of the First World War, Vienna counted more than two million inhabitants. In addition to the intellectual capital and the cultural dimensions of a concentrated urban population, humans also generate a significant amount of waste, which creates challenges for urban administrators. A human generates an average of 1.3 kilograms of solid and liquid waste each day. With a total population of just over 2 million on the eve of the First World War, this means an estimated 2.6 million kilograms of waste to deal with each day (Gierlinger et al. 2013, 229). In addition to this, the frequent use of horses for transportation and hauling in the years before the widespread adoption of automobiles meant an even larger amount of organic waste. Horses, on average, generate 24 kilograms of solid and liquid waste each day (Hennessy and Eriksson 2015, 7). Although precise figures are not available, it is clear that a large amount of non-human waste was generated in addition to the daily human waste that the population had to contend with.
In the nineteenth century, the city debated how best to approach this problem. Some argued for a comprehensive sewer system, others argued for the implementation of a sophisticated bucket or barrel system. In the former instance, the city would simply expand the already-existing sewer network, In the latter, each building would be outfitted with a sealed container hooked up to the toilets in the building (See Figure 2). Each of these systems had advantages and disadvantages. Expanding the sewer system would have been much more comprehensive and sanitary, but it would cost much more to implement. In addition, there were concerns about the relative lack of adequate water supplies, without which solid waste would accumulate in the sewers without being washed away. In 1871, city officials estimated that they would need approximately “three buckets per head per day” to ensure waste was appropriately disposed of (Innhauser and Nusser 1872, 10).
The implementation of a bucket/barrel system had fewer advantages, with less cost for the city being its chief virtue. In fact, there would still be significant issues with waste disposal in a bucket/barrel system. For example, if an apartment building of four stories contains five living units each, with an average of four people per apartment, each building contains eighty people who generate an average of 104 kilograms of waste per day. Given the average capacity of a waste barrel of approximately 45 liters, this would necessitate removal and replacement several times each day (Angelakis 2014, 440). This was by no means guaranteed to happen, particularly in poorer neighborhoods unable (or with landlords unwilling) to pay for such frequent cleaning.
The barrel method would also have been much more uneven, as the two million inhabitants of Vienna were not evenly dispersed throughout the city. In 1914 the two most populous districts in Vienna were the XVI and II, containing 190,627 and 180,580 individuals, respectively. This is about four times as many residents as the old First District (47,318), which also had the oldest and most continuous sewer coverage (Statistical Yearbook of the City of Vienna for the year 1914, 45). Sewer coverage by this time was extensive, but it is possible that numerous households still relied on cesspools or the bucket/barrel system for waste disposal, particularly in the XVI district which was further away than the II district from the inner core of the city. Furthermore, of the approximately 9,500 residential buildings recorded in 1914, nearly one third were located just within two districts, the tenth and the fifteenth. Conversely, less than half a percent of residential buildings was located within the first district, comprising the old inner city. This disparity was evident in density as well. The vast majority (ninety percent) of residences were between one and four floors. The tenth district, however, also had 293 residences with five floors (Statistical Yearbook of the City of Vienna for the Year 1914, 11). Accurate statistics for the number of people in each building are difficult to come by given both informal housing and the difficulty inherent in counting all individuals. Nevertheless, it is clear that a larger building can hold more people, leading to even higher levels of waste generation. The approximately 172,000 residents of the Tenth District would have generated 246 tons of waste daily (Statistical Yearbook of the City of Vienna for the Year 1914, 45).
With the opening of the First Mountain Spring Pipeline, the city made the decision to implement a broader and more comprehensive sewer system much easier. The First Mountain Spring Pipeline was estimated to have been able to supply 138,000 m3 per day, or 36.5 million gallons (Statistical Yearbook of the City of Vienna for the Year 1914, 178). Although the size of a bucket in the “three buckets per head per day” estimate made in 1871 was not defined, even assuming a fairly liberal definition of five gallons per bucket meant 10 million gallons were required daily for the smooth functioning of the sewer system – a figure easily met by the pipeline. Costs remained, however, and they were significant. A report from 1914 indicated that the total expenditures of the city in setting up the mountain spring pipeline necessary to get the sewer system running effectively was 93,886,621 Austrian Krone, which did not include the cost for laying new sewer pipes, or covering naturally-existing waterways and transforming them into sewers, as frequently happened (Statistical Yearbook of the City of Vienna for the Year 1914, 178).
Regardless, the expense was clearly seen as necessary to promote the health and wellbeing of the residents, as well as the smooth functioning of the city. In the remarks given to the Emperor and Empress upon the opening of the Ringstraẞe on May 1, 1865, mayor Zelinka made the explicit connection between clean water access and urban health when he said that: “The water pipeline that is so eagerly awaited, which is required for the cleanliness of the city and for the health of its inhabitants, will crown the great value of urban expansion, and as the founder of it, Your Majesty will earn the gratitude of even the coming generations” (Wiener Zeitung, May 1, 1865). Although few users of the Viennese sewer system today are likely to thank the Emperor for its implementation, the city still benefits from the large infrastructure projects undertaken over a century ago.
 Numbers used for illustrative purposes and not necessarily reflective of the average numbers in the city, but many buildings likely did contain a similar arrangement
 After adjusting for the European convention of naming the first floor “ground floor,” the second floor “first floor,” and so on.