Sanitary Sewer Overflow Along Dakota Avenue, Feb. 27

City of Coos Bay release – A significant amount of rainfall has occurred over the last several days.  As a result, the sanitary sewer system has been at capacity and surcharged in many areas throughout the City.  This is caused by inflow and infiltration (I/I).  I/I occurs when ground water and surface water enter into the sewer system through deficiencies in the pipe and manholes.  Unfortunately, this is a common condition in aging systems. Monday, February 25, 2019, at 7:35 am ponding was reported along Dakota Avenue just west of Southwest Boulevard.  This ponding was a result of the sewer system being over capacity and surcharged.  The City’s wastewater contractor mobilized and pumped the ponded sewer flows into tanker trucks.  The storms subsided later that day and the ponding receded.   The SSO event occurred for approximately two hours, and it was estimated that 2,000 gallons escaped the sewer system and entered Coal Bank Slough. This overflow was reported to Oregon Emergency Response System (OERS) and Oregon Department of Environmental Quality (DEQ). If you notice abnormal ponding occurring, please don’t hesitate to contact the Public Works Department to investigate the situation. Your cooperation is greatly appreciated. Any questions can be directed to the City of Coos Bay Public Works Department at (541) 269-8918.