What is FOG?

FOG is an acronym for fats, oils, and grease, particularly in the context of wastewater collection systems. Cooking grease, animal fats, vegetable oils, shortening, butter, food scraps (especially from garbage disposals), and dairy products that are allowed to go into a sink drain can create issues for plumbing systems and the City of Hickory's sanitary sewer system. These fats, oils, and greases collect and build up on the inside of sewer pipes, slowly causing them to close and then finally stop up completely.

FOG is the leading cause of sanitary sewer overflows in North Carolina. Sanitary sewer overflows (SSOs) are clogs in the collection system that can potentially result in raw sewage being released into communities, causing potentially dangerous health conditions. These are costly events for wastewater utilities to clean up, dangerous for public health, and can degrade the water quality of North Carolina's public waters.

Why should we care about FOG?

Wastewater overflows, or sewer spills, cost everyone. Sewer spills must be corrected by the dispatching of a maintenance crew with specialized equipment to remove the cause of the blockage. This is both expensive and unpleasant, and the customers of the system pay for all operational expenses. Fewer maintenance calls results in lower operational expenses and stable rates. 

Sewer overflows will cause sewage to spill into streets, creeks, streams, parks, and yards. These spills are unsightly and potentially have a negative impact on the environment. 

Sewer spills can be very expensive! Backups into homes can be costly and very unpleasant to clean for both the resident and the City. If the blockage is on the customer's side or can be tracked back to a specific customer, then it would be that customer's responsibility to fund or directly clean up all damages.

Keep sewer rates from increasing excessively by stabilizing maintenance requirements and creating predictable maintenance needs.

Let's compare the sewer system to the cardiopulmonary system of the human body. A wastewater treatment facility acts as the heart, as everything eventually ends up going through it. The main trunk lines act as arteries that carry the wastewater from the laterals of the homes like the veins and vessels of the human body. The buildup of fats, oils, and grease constricts the flow and eventually causes blockages, resulting in a heart attack, or in this case a sewer overflow. We are mindful of the things that we put in our body, so let's be mindful of the things that we put in our sewer system.

What are household tips to reduce FOG?

• Do NOT put fats, oil, or grease down the drain.
• Collect oil and grease in containers and allow to congeal or place in the freezer. Place in the garbage afterwards.
• Remove food waste with "dry" methods like wiping with a paper towel and then discarding in the trash.
• Put strainers in the sink to catch food scraps and other solids and empty them into the trash.
• If you see a manhole overflowing, call City of Hickory Public Utilities at (828) 323-7427 immediately.

FOG Program

The City of Hickory's FOG program administers the Oil and Grease policy in accordance with the City of Hickory's Sewer Use Ordinance; promotes the reduction of sewer overflows; protect the City of Hickory’s infrastructure by preventing the buildup of FOG in collection system lines, pumps, and equipment; meets with the City of Hickory’s approximately 250 FOG contributors on a one-on-one basis to educate, inspect grease interceptors for compliance, gather information, and reinspect for compliance, if needed.

Sources of FOG

• Restaurants
• Households
• Industrial cafeterias
• Schools
• Hospitals
• Nursing homes

How does a grease interceptor work?

A properly designed and maintained oil and grease interceptor allows solids, oils, and greases to be trapped, while allowing water to flow from the interceptor into the collection system. In order to properly maintain the interceptor, the oil and grease must be pumped from the interceptor on a regular schedule by an approved company. This helps reduce oil and grease in the collection system.