Key facts: What not to pour down drains
- Fats, oils and grease cool and harden in sewer pipes and can combine with wipes into large masses called fatbergs [1].
- Henderson requires restaurants and other food service businesses to fit and look after grease interceptors under Henderson Municipal Code 14.09 [2].
- Chemical drain cleaners are strongly caustic or acidic, and mixing products can be dangerous [3].
- Henderson's wastewater is treated at Henderson's Kurt R. Segler treatment plant and reused for parks and golf courses [4].
At a glance
The do-not-pour list
Print it, screenshot it or stick it inside a cabinet door.
| Item | Why it is a problem | Put it here instead |
|---|---|---|
| Cooking grease, oil, bacon fat | Cools into a waxy layer that narrows pipes | A lidded can, then the trash once solid |
| Butter, sauces, gravy, dairy fat | Same as grease, just hidden in liquid | Scrape or wipe into the trash |
| Coffee grounds | Settle into gritty sludge in traps | Trash or compost |
| Rice, pasta, oatmeal | Swell with water and clump | Trash or compost |
| Eggshells and fibrous peels | Sharp bits and strings catch debris | Trash or compost |
| Wipes of any kind | Do not break down like toilet paper | Trash can, even if labeled flushable |
| Paint, solvents, motor oil | Coat pipes and harm treatment | Household hazardous waste drop-off |
| Mixed drain chemicals | Can react and release harmful fumes | Use one product only, or skip them |
Grease first
Why is grease the biggest drain problem?
Hot grease pours like water, which is exactly what makes it sneaky. As soon as it reaches cooler pipe, it starts to firm up and cling to the walls. Each greasy pan adds another layer.
Grease also teams up with other things. Combined with wipes and food scraps, it can form solid masses that utilities call fatbergs, some large enough to block city sewers [1].
Hot water and dish soap do not solve it. They move the grease a few feet further along before it cools again, often somewhere harder to reach.
Already have a stubborn blockage? Here's how clogged drain repair usually works.
Henderson detail
Hard water makes grease stick faster
Henderson water is very hard, around 16 grains of hardness per gallon according to the city [5]. That leaves a rough mineral lining inside drains, and grease grips rough surfaces far better than smooth ones.
The upshot is that habits which might get by in a soft-water city cause trouble here sooner. Keeping grease out of the sink matters more, not less. Our guide to hard water scale in drains explains the mineral side in more depth.
Room by room
What to watch in each part of the house
Kitchen
Grease, coffee grounds, starchy foods, eggshells, fruit stickers and fibrous peels such as celery or onion skins. Garbage disposals grind food smaller but do not make grease disappear.
Bathroom
Wipes, cotton swabs, floss, hair, and feminine products. Only toilet paper belongs in the toilet. Hair is best caught with a strainer before it reaches the pipe.
Laundry
Lint from heavily shedding items, sand from pool towels and large amounts of powdered detergent. A lint trap on the washer discharge hose helps.
Garage and yard
Paint rinse water, motor oil, antifreeze and pool chemicals. These do not belong in any drain and are handled through hazardous waste collection.
Holidays and gatherings
Big meals, big risk
Thanksgiving turkeys, Sunday roasts and backyard barbecues all leave far more fat behind than a normal weeknight dinner. Roasting pans in particular hold a surprising amount of drippings that look harmless once diluted with dishwater.
Before guests arrive, set out a grease can and a lined bin next to the sink so helpers have an obvious place for scraps. Ask anyone washing up to scrape plates into the trash first. These small steps keep a festive weekend from ending with a sink full of standing water.
Remember what not to pour down drains applies to leftovers too. Old soup, gravy and pan sauces carry hidden fat, so let them cool, skim or solidify them, and bin the result.
For restaurants and cafés
Henderson's grease rules for businesses
Commercial kitchens play by stricter rules. Under Henderson Municipal Code 14.09, food service establishments must install and maintain grease interceptors, and each interceptor can serve only one business [2]. The locally adopted plumbing code also requires interceptors for grease-laden waste [2].
Interceptors work by slowing wastewater so fats float and solids sink before the water moves on to the sewer [6]. They only work if they are pumped and cleaned on schedule. Business owners can learn more on our commercial drain cleaning page.
Easy wins
Simple habits that prevent most clogs
- Keep an old can or jar by the stove for grease, and toss it when it is full and solid.
- Wipe plates and pans with a paper towel before rinsing.
- Put mesh strainers in the kitchen sink, tub and shower.
- Keep a small trash can in every bathroom so wipes and swabs have somewhere to go.
- Run the disposal with plenty of cold water and feed it slowly.
- If a drain has clogged before, ask about preventative drain maintenance.
When it is too late
Already poured something you should not have?
One mistake rarely causes a clog by itself. Run plenty of hot tap water and watch the drain over the next few days. If it starts slowing, gurgling or smelling, that is the time to act.
A kitchen sink that will not drain is a job for kitchen drain cleaning. If water is rising out of the sink or dishwasher and you cannot stop it, check whether emergency kitchen drain cleaning is available.
FAQ
Questions about what belongs down a Henderson drain
Spoken questions about what not to pour down drains, answered briefly. Other topics: [questions hub](/faq/). Back to [more plain-English guides](/guides/).
What is a fatberg and can one form in my home's sewer line?
A fatberg is a mass of congealed fats, oils and grease bound together with wipes and other debris, and similar buildups can start in household lines [1]. Grease cools and hardens inside pipes, then catches anything that passes. Keeping grease and wipes out of drains is the simplest way to stop that buildup forming between your kitchen and the street.
Where should I put used cooking oil instead of the kitchen sink?
Used cooking oil is better poured into a sealable container, cooled, and placed in the trash rather than the sink. Liquid oil cools and hardens in pipes and can combine with other debris into stubborn blockages [1]. Wiping greasy pans with a paper towel before washing also keeps a surprising amount of fat out of the drain line.
Are used coffee grounds bad for kitchen drains and garbage disposals?
Used coffee grounds are a common kitchen drain problem because they don't dissolve and tend to settle into a dense sludge in traps and pipes. A disposal grinds them smaller but doesn't make them disappear. Combined with grease, grounds can form heavy deposits. Composting or binning them is usually the gentler option for both disposals and household drain lines.
Is it safe to mix bleach with a drain cleaner to unclog a sink?
Mixing bleach with a drain cleaner is not safe, because combining chemical products can produce dangerous reactions and fumes [3]. Drain cleaners are already strongly caustic or acidic on their own. If a product hasn't cleared the sink, stop adding more and ventilate the room. Tell the contractor you're connected with exactly what was poured so they can work safely.
Do Henderson restaurants have special rules about grease going down drains?
Henderson restaurants and other food businesses have to install and keep up grease interceptors under Henderson Municipal Code 14.09 [2]. The interceptor catches fats, oils and grease before they reach the public sewer. Business owners should keep up with interceptor maintenance and train staff on what goes down drains, since grease is one of the most common commercial line problems.
Can I flush paper towels or tissues if I run plenty of water?
Paper towels and facial tissues are designed to hold together when wet, so extra water won't make them break down like toilet paper. Towels and tissues tend to snag in toilet traps and laterals, where they join grease and wipes [1]. Putting them in a bin is the safer habit, even if a single flush seems to go down without trouble.
What happens to Henderson wastewater after it leaves my drains?
Henderson wastewater is treated at the Segler reclamation plant run by the city, and the treated water is reused for parks and golf courses [4]. Grease, wipes and harsh chemicals make that process harder and can block lines long before reaching the plant. Keeping them out of drains protects both your own pipes and the shared system downstream.