How big is the Metropolitan St. Louis Sewer District?

MSD is the fourth largest sewer system in the United States based on wastewater sewers. Although MSD’s service area is moderate compared to other municipalities, the system is expansive and complex. Los Angeles’ sewer system, which serves five to six million residents, is of comparable size. Though its sewer footprint rivals that of Los Angeles, Chicago and New York, it has a much smaller customer base upon which to rely for system improvements.

Providing service to more than 467,000 customers in St. Louis City and about 80% of St. Louis County, the District maintains:

• 7 treatment facilities processing 330 million gallons of sewage daily

• 2,980 miles of stormwater sewers

• 4,741 miles of sanitary sewers

• 1,928 miles of combined sewers