Sewer Modeling in Seattle Helps Ease Overflow Woes

摘要

The first permanent sewer in Seattle, Wash., was laid in 1883, and the original sewer trunk system was constructed between 1892 and 1911. Initially the sewers were constructed as a combined system, and untreated sewage was deposited in the convenient waters on both sides of the city. The early 1900s saw the start of construction providing partial separation of stormwater from sanitary flow. As the system expanded, some of the storm-water was separated, and the remaining wastewater was diverted for treatment to lessen the pollution load in the surrounding waters. Subsequently, several large trunks were built to link the many communities surrounding Lake Washington and on the eastern shore of Puget Sound with secondary waste-water treatment plants operated by King County, adjacent to Seattle.