DRYmedic Restoration Services A sewer drain clog can be a serious issue that can result in a plumbing emergency or a potential health concern. Read below to learn more about how to prevent and treat sewer blockage. Common Causes of a Sewer Blockage ● Aging Sewer systems ● Oil, grease, or fat build-up in the pipes. Avoid pouring these things down the kitchen sink. ● Flushing non-septic-safe items in the toilet. Such as wet wipes and feminine hygiene ...