The holidays are a time for indulgent foods: Gravy, fatty meats, baked treats and more. 

These foods may be central to a traditional holiday feast, but can cause major problems with clogging pipes — more specifically, the sewer pipes underneath homes. 

Fats, oils and grease are found in many holiday staples. If not disposed of properly, however, they can wreak havoc on homeowners' plumbing and the nearby sewer system. When washed down the drain, the fats and oils can create sewer backups across utility systems that require costly repairs. 

And they have.

In recent years, Citizens Energy Group, a utility provider serving central Indiana, has responded to nearly 100 incidents of sewer backups directly caused from fatty and greasy foods. That's on an annual basis. Depending where the backups are located within the pipes, Citizens said the blockages can require costly and lengthy repairs.

Why are there plumbing issues around the holidays?

During the holidays, people are often cooking larger meals with higher fat foods. Think of a big roast with rich gravy on the menu, or deep-frying a turkey around Thanksgiving.

But it's what folks do with the leftover fats and oils that causes problems to pop up. 

When homeowners wash fats, oils and grease down the drain or garbage disposal, or flush it down the toilet, they enter the sewer system in a liquid state. But as they cool, the fats and oils solidify and attach to the sewer system's pipes and joints. 

Over time, those solid deposits can block the pipes and cause backups. According to Citizens, residents will know when they have a problem. Waste water can come back up in sinks, toilets and basement drains.

Holiday travel:As Thanksgiving Eve became 'Blackout Wednesday', a spike in DUI crashes followed, NHTSA says

How do you repair plumbing issues?

If the plumber either rules out or clears an oily backup in the homeowner's plumbing system, but the issues continue, that may indicate the backup is on the larger system. That's the time to call your utility provider.  

A utility service, like Citizens, will inspect the nearby sewer system, often with a camera. If a grease-related clog is identified, then the company will take steps to remove it. The first step is to get excess liquid out of the pipes by vacuuming it out with a sewer cleaning truck. Then the backup is removed using the same truck with cleaning tools attached to the flushing hose and vacuum equipment. 

Citizens said it must respond to blockages with urgency, including both the removal and investigating the source of origin. According to the utility company, there may also be fines and penalties for homeowners.

How do you prevent holiday plumbing issues?

Compared to the potential problems and costs at stake, reducing backups from fats, oils and grease is "easy to do and well worth your time," Citizens said. Stop the problem before it's a problem.

Residents should never pour fats and oils down an inside drain, the garbage disposal or even a storm drain in the street, according to the utility company. Also, using hot water or soap will not prevent backups or wash the grease through the pipes.

Instead, Citizens recommends a few different steps to correctly dispose of fats, oils and grease: 

• Pour the fats, oils and grease into a small, disposable container and either leave out at room temperature or place it in the fridge. Once it solidifies, place the container in the trash. 
• Wipe grease off pots, pans and dishes before washing them. This is best done with a dry paper towel that you throw in the bin after. Don't do this with a sponge, because that will still result in the fats and oils going down the drain. 
• For restaurants or other food preparation establishments, fats, oils and grease can be a valuable resource as a recyclable. They can be sold to rendering companies for use in soaps, fertilizers and animal feed. 

What restaurants are open Thanksgiving?Details on Starbucks, McDonald's, fast food, more

Call IndyStar reporter Sarah Bowman at 317-444-6129 or email at [email protected]. Follow her on Twitter and Facebook: @IndyStarSarah. Connect with IndyStar’s environmental reporters: Join The Scrub on Facebook.

IndyStar's environmental reporting project is made possible through the generous support of the nonprofit Nina Mason Pulliam Charitable Trust.