Combined Sewer Overflow

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Clean waterways are a priority in Mishawaka. We are implementing many projects to improve our waterway and to reduce combined sewer overflows. These efforts include expanding and modernizing our wastewater treatment plant and improving the sewage collection system.

What is a Combined Sewer Overflow? (CSO)

CSOs occur when the capacity of the sewer system and treatment plant are exceeded, due to rainfall or snowmelt. When this occurs, the excess mixture of stormwater and sanitary sewage is discharged to the river through combined sewer overflows. (see "Why Sewers Overflow"). The greatest impacts of discharges from CSOs are associated with bacteria in the untreated sewage and in the stormwater run-off. Bacteria levels in the river can rise for several days following a CSO discharge. Notification signs have been posted at CSO outfall locations and at access points along the river. (see "Mishawaka CSO Locations").

How can I help?

  • Disconnect downspouts and sump pumps from the sewage system.
  • Clean up after your pets.
  • Dispose of household chemicals and used oil properly - not down the drain or a storm sewer.
  • Reduce water use and keep pollution out of the storm drains.
  • Invite us to make a presentation to your civic association or neighborhood group. 

These simple steps can make a world of difference in Keeping Mishawaka Beautiful.

Large boulder outside Wastewater Treatment plant entrance inscribed with Mishawaka Utilities Logo




1020 Lincolnway West

Mishawaka, IN  46544

Phone (574) 258-1655

Fax (574) 255-3557