Why liquid oil still causes clogs
Olive oil is liquid in a warm kitchen but cools and thickens as it travels through colder pipes. It clings to the pipe wall, picks up food particles and soap, and forms a sticky layer. Over time the layer narrows the pipe, and the next piece of food or hair catches on it. The blockage that finally stops the drain looks like a lump of food, but the oil built the trap.
Olive oil is also an ingredient in many foods that end up in the sink, from salad dressings to pasta pans. The oil is rarely poured on its own. It goes down mixed with other things, and that mix is what sticks.
What happens downstream
- Oil coats the pipe and holds food and hair, shrinking the opening.
- Cold water in the line makes the oil thicken and cling.
- A partial blockage can slow drains for months before it stops.
- Oil from many homes joins in the city sewer, where it can cause overflows.
- Soap can combine with oil and minerals to form a hard deposit.
| Item | Risk in the drain | Better disposal |
|---|---|---|
| Olive oil and other liquid oils | Cools and clings, builds a coating | Cool, seal in a container, trash |
| Bacon grease and butter | Solidifies quickly | Collect in a can, trash |
| Salad dressing and sauces | Oil mixed with food | Scrape plates, wipe pans |
| Pan drippings | Hot oil and food bits | Wipe with paper towel, trash |
| Large amounts of used oil | Too much for the trash | Take to a disposal station |
Port Hueneme note: what the city says about cooking oil
The City of Port Hueneme runs a state-required Fats, Oils and Grease program. Its guidance says never to pour grease, oil or fat down a sink, and that sink drains and garbage disposals are not built to handle it. The city page does not name olive oil, so we say cooking oil. The same guidance applies.
For up to about a quart, the city says let used cooking oil cool and solidify, or mix it with kitty litter, and put it in the trash. For larger volumes, cool the oil, put it in a labeled leak-proof container and call the Water Resource Inspector at 805-986-6661 for a disposal station.
The city warns that fats and oils can combine with roots to cause sewer backups and overflows, and food businesses must have grease devices serviced and keep hauler receipts for two years.
Drain slowing down?
Call and tell us what is happening. We clear the line and explain what to change.
What to do instead
- Wipe greasy pans with a paper towel before washing.
- Let small amounts of used oil cool and put them in the trash in a sealed container.
- Scrape plates into the trash or compost before rinsing.
- Use a sink strainer to catch food scraps.
- Take larger amounts of used oil to the disposal station the city lists.
Hot water and dish soap do not make oil safe to pour. They only carry it further, where it cools. The same is true of a garbage disposal. A disposal grinds food but does nothing to keep grease from coating the pipes beyond it.
If the drain is already slow
A mild slowdown may respond to a flush of hot tap water with dish soap. A heavier coating needs mechanical cleaning. Our drain cleaning service uses cable machines with cutting heads for kitchen branch lines, and hydro jetting washes the full pipe wall when buildup is heavy. A camera inspection shows how bad the coating is before you decide.
If the whole house backs up, the grease may be in the main line. See sewer line cleaning. Restaurants face the same problem on a larger scale, and our commercial plumbing service handles kitchen lines.
Where we work
What to do with cooking oil instead
Let used oil cool, pour it into a sealable container and put it in the trash. A coffee can with a lid works, and so does the jar the oil came in.
Wipe greasy pans with a paper towel before washing them. That small habit keeps most fat out of the trap and out of the line.
If a sink is already slow after a greasy meal, do not keep running hot water to flush it. Call before the fat hardens into a plug that needs a machine to clear.
We clear grease from kitchen and main lines across Port Hueneme and in Oxnard and Channel Islands Beach. Tell the dispatcher what has gone down the sink, because it helps us choose the right tool.
Questions Port Hueneme homeowners ask
The city says never to pour grease, oil or fat down a sink. A little at a time adds up, so put small amounts in the trash in a sealed container.
The city page does not name olive oil. It covers cooking oil, and the same advice applies.
The city says to cool it, put it in a labeled leak-proof container and call the Water Resource Inspector at 805-986-6661 for a disposal station.
It may help a mild slowdown but it only moves the oil along. Heavy buildup needs a cable or a jetter.