"The majority of sanitary sewer overflows are caused by the accumulation of fats, oils, and grease and other debris, such as wet wipes, diapers, rags, and hygiene products, in the sewer pipes."Also from the city about reporting an issue: Contact the City immediately when experiencing or observing a sanitary sewer problem. The easiest and most effective way for the public to report such an incident is to call one of the following phone numbers:
Weekdays, 7:00 a.m. to 4:00 p.m.: DOT Dispatch (408) 794-1900
Evenings, Nights, and Weekends: City Communications (408) 277-8956
More information is available on the city's web site.