Holiday cooking puts more grease and food scraps down the kitchen drain than any other time of year. Bay Area sewer agencies see the result every November and December with more backups, more overflow, and a lot of frustrated homeowners. A few simple habits at the sink keep your pipes clear while the house is full.
Why Grease Clogs a Drain
Grease is a liquid in the pan and a solid in the pipe. Hot water and dish soap carry it a short way down the line. Then the pipe cools it, and it hardens on the walls. Every meal adds another thin layer. The pipe narrows until a potato peel or a lump of pasta stops the flow.
The plug can form in your own line. It can also form in the city sewer main, where it sends overflow into streets and creeks.
What a Garbage Disposal Does and Does Not Do
A disposal grinds food into small pieces. It does not dissolve fat. The ground scraps and the grease still travel down the same pipe. Los Altos, for one, asks residents to scrape dishes into the trash before they use the disposal.
Running hot water or adding dish soap does not change this. The grease cools farther down the line and hardens there.
What to Keep Out of the Disposal
Skip these during holiday cooking:
- Fat, oil, butter, gravy, and pan drippings
- Pasta and rice, which swell in water
- Potato and onion peels
- Celery, carrots, and other stringy vegetables
- Bones and poultry skin
- Coffee grounds
- Dough and batter scraps
- Eggshells (plumbers disagree about them, so the trash is the safer choice)
A disposal handles small, soft scraps. When you are unsure, use the trash or the compost bin.
Where Grease Goes Instead
Let it cool first. Pour small amounts into a container with a lid, then put the container in the trash. Wipe greasy pans with a paper towel before you wash them.
Some haulers accept paper towels with small amounts of fat in the green cart. Check your hauler’s rules before you try it.
Large amounts need a different route. Santa Clara County’s Household Hazardous Waste program takes used cooking oil by free appointment. Up to a quart can go in the trash. For more, pour the cooled oil into a sealed container and book a drop-off. Palo Alto residents use the city’s own program. On the Peninsula, ask your city or sewer district where to take it.
Signs Your Drain Is Already Struggling
Check the kitchen sink before the guests arrive. These signs mean the line needs attention:
- The sink drains slowly.
- The drain gurgles after the dishwasher runs.
- A smell rises from the sink.
- Water backs up into the second basin when the disposal runs.
A slow drain will not cope with a full week of cooking. A plumber can clear it first. A cable opens a path through the clog. Hydro jetting washes the grease off the pipe walls. Our article on how hydro jetting clears stubborn drain lines explains the difference.
When More Than One Drain Backs Up
If the kitchen sink, a shower, and a toilet all slow down together, the blockage sits farther down the line. If the cleanout outside your house overflows, the main line is blocked. Stop using water and call a plumber. A sewer camera inspection shows where the blockage sits and what caused it.
Frequently Asked Questions
Can I pour cooking oil down the drain if I run hot water with it?
Hot water only moves the oil farther down the line. The pipe cools it, and it hardens there. Pour the oil into a lidded container instead.
Does a garbage disposal make pan drippings safe to wash down?
No, it does not. The disposal cuts food into pieces and leaves the fat alone. Let drippings cool, then throw them out in a sealed container.
What should I do with a large amount of fryer oil?
Cool it, seal it in a container, and take it to a drop-off site. Santa Clara County’s Household Hazardous Waste program accepts it by appointment. Palo Alto runs its own program.
Is the clog in my pipe or in the city sewer?
If only your house backs up, the clog most likely sits in your own line. If sewage shows in the street or neighbors report the same problem, call your city’s public works office or sewer district. A camera inspection shows what sits in your line.
Clear the Drain Before the Guests Arrive
A slow kitchen drain gets worse under holiday use. If yours is already draining slowly, call JetPipe Plumbing at (650) 495-4570 or schedule a visit online. We clear drains with cable and hydro jetting and service garbage disposals throughout the Peninsula. You can read more about our drain cleaning service.
Kitchen sink already draining slow before the holidays?