Answer:

Like many cities in the United States, portions of the City of Fort Wayne use a single pipe to carry a combination of sanitary sewage and storm water. During dry weather, the pipe capacity is adequate to carry sanitary flows to the wastewater treatment plant. When it rains, the added stormwater can overwhelm these combined sewer lines and the system discharges combined sewage and stormwater through a number of outfall locations to the rivers. 3RPORT and the Tunnel Works program will significantly reduce the number of times in a typical year that these overflows occur. 

Combined Sewers Diagram

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