Decatur Utilities says with more than four inches of rain in the forecast, Sanitary Sewer Overflows (SSOs) are expected through the weekend in some areas of the city.

The utility says these overflows happen when the “sewer collection system is overwhelmed by heavy rains that infiltrate pipes through cracks, holes, loose joints, broken pipes, and leaking manhole covers.”

Customers living in an area affected by an overflow receive an automated phone call from the utility, said a Decatur Utilities spokesman, Joe Holmes. He says these areas are marked with SSO signage and pink SSO flags.

According to Holmes, overflows caused by heavy rain can last for two to three days after the rainfall ends. He says these areas are cleaned and disinfected once the overflow stops.

The public should avoid coming into direct contact with an overflow. The utility says there is no impact on drinking water.

Heavy rains in December pushed more than three quarters of a million gallons of sewage out into Decatur streets. You can read our story on that here.

Decatur Utilities released this statement on Thursday:

With more than four inches of rain expected in Decatur through Friday afternoon, Decatur Utilities advises that Sanitary Sewer Overflows (SSOs) are expected to occur through the weekend in historically affected areas of Decatur.

SSOs occur when the sanitary sewer collection system is overwhelmed by heavy rains that infiltrate pipes through cracks, holes, loose joints, broken pipes, and leaking manhole covers. (SSOs can also be caused by accumulation of fats, oils and grease, root intrusion, unforeseen mechanical failures, and pipe defects.)

Residents within the immediate area affected by an SSO are notified by an automated phone call from DU. Areas are also clearly marked with SSO signage and pink SSO flags. SSOs caused by heavy rains can continue to overflow for two to three days after rainfall stops. Areas affected by an SSO are cleaned and disinfected once the SSO stops.

While rain-induced SSOs are heavily diluted by rainwater, DU advises residents to avoid coming into direct contact with the overflow. If contact is made with skin, residents should wash normally with soap and water. Any clothing that comes in contact should also be washed normally.

DU has been aggressively addressing SSOs over the past 10 years and has spent more than $60 million on sanitary sewer system improvements. DU is also fully committed to continuing improvements in an effort to reduce/eliminate future SSOs.

DU’s drinking water is not impacted by SSOs and is safe to consume.