On December 4, 1885, the Seattle City Council approves Ordinance No. 696, requiring that residential property be connected to existing sewer lines. Mayor Henry Yesler (1810-1892) signs the ordinance the same day. At the time, a great many homes in the city have no sewer lines to attach to. Not until the 1890s will Seattle begin construction of a city-wide sewer system.Sewage and Disease
During the nineteenth century, as more and more people crowded into cities, particularly in Europe, with the advance of the Industrial Revolution, and as scientists began to understand the causes of disease, the connection between sewage disposal and health began to be made. Awareness of sanitation and the importance of sewage disposal grew around the world after 1854, when a cholera epidemic in London, England, claimed more than 10,000 lives, and spurred a frenzy of sewer construction.At the time of London's epidemic Seattle was a new settlement of a few hundred people, but its population grew rapidly over the next three decades. In the mid-1870s, Seattle experienced several diphtheria epidemics that killed many young children and some entire families.
In the early 1880s the first rudimentary sewers were installed in the city, including wooden-box sewers in Yesler Way and James Street and a vitrified clay pipe along Union Street from 8th Avenue to 1st Avenue. Other early sewers and cesspools were little more than open ditches that endangered the health of residents and contaminated springs and other water sources.Connecting to Sewers -- and Building Them
By 1885, half way through a decade in which Seattle's population grew more than 10-fold, from fewer than 4,000 to more than 42,000, city officials decided that all residences should be connected to sewers. Ordinance No. 696, passed by the city council and signed by Mayor Yesler on December 4, 1885, mandated that residential property be connected to existing sewer lines. But it did not call for the construction of additional sewers, and there were no lines for many residences to connect to.In addition, most of the lines that did exist discharged untreated sewage into the water bodies that surrounded the city -- Lake Washington, Lake Union, and Elliott Bay. Although tides and currents dispersed sewage flowing into the bay, the lakes, then still a source of drinking water, became increasingly polluted. In 1889 city officials consulted sewer expert George E. Waring Jr. (1833-1898), who prepared a design for a sewer system. Waring did not include plans for handling stormwater (rain and snow runoff), which he believed could be handled on the surface. That seemed unlikely to those familiar with the volume of stormwater during Seattle's rainy winter months, and officials likely feared that building Waring's sewage-only system would soon require costly construction of a separate system for stormwater.
Instead, the city turned to hydraulics engineer Benezette Williams (1844-1914), who also prepared the first plans for Seattle's Cedar River water-supply system, to design a combined sewer system to carry both sewage and stormwater to outfalls in the bay and lakes. The city council adopted Williams's plan in 1891, and, like his Cedar River design, it was implemented over the following years by City Engineer R. H. Thomson (1851-1949). In 1892, with half the city's population (three-quarters of its land area) without sewers and cholera threatening the West Coast, Thomson recommended construction of 50 miles of sewer lines. Work got under way the following year.As he did with the water-system plans, Thomson made significant changes to Williams's sewer design, in particular rejecting a plan to direct some sewage to Lake Washington. Nonetheless, the decision to build a combined system, rather than separate ones for sewage and stormwater, would have consequences -- including discharge of untreated sewage into the lakes and bay during heavy rainfalls -- that the city would be dealing with through the twentieth century and into the twenty-first.