Each year, approximately 9 billion gallons of wastewater overflow into our region’s waterways. Because of that, ALCOSAN is not in compliance with the federal Clean Water Act.
To fix this, ALCOSAN has started a $2 billion, long-term, Clean Water Plan that will reduce the amount of combined sewage overflow by 7 billion gallons per year and eliminate sanitary sewage overflows. To achieve this, ALCOSAN’s plan involves four major components:
265 Miles of Sewer
8 Wet weather control facilities
77 Diversion structures
Learn how ALCOSAN is working with municipalities to take ownership of trunk sewers and related facilities to create a streamlined system.
Follow updates on ALCOSAN’s plant expansion plans.
150+ feet deep, 4.9 miles between 14 and 18 feet in diameter, with anticipated construction in 2025-2029 timeframe.
150+ feet deep, 6.2 miles and 18 feet in diameter, with anticipated construction in 2028-2034 timeframe.
150+ feet deep, 5.4 miles and 18 feet in diameter, with anticipated construction in 2030-2036 timeframe.
Learn about the changes at ALCOSAN that are underway to accommodate flow.
Learn about the changes at ALCOSAN that are underway to accommodate flow.
This virtual meeting will provide viewers with updates on the Authority’s Clean Water Plan activities.
VideoLooking for more technical information? All of our plans and formal documents may be found here.
DocumentsALCOSAN makes mapping related to the regional sewer systems and our region’s waterways available to the public.
See MapsA combined sewer overflow (CSO) occurs when stormwater and untreated, diluted sewage, overload the sewer system and flow into rivers and streams.
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