The short version: human waste, toilet paper, and water. Everything else is somewhere between a bad idea and an expensive one.
The worst offender, by a distance
Flushable wipes. They are not flushable in any meaningful sense. The word describes whether they will leave the bowl, not whether they will make it through your sewer line, and they will not — they do not break down like paper. They snag on any roughness in the pipe, catch each other, and build a mass.
On a municipal scale these combine with grease into the things water companies have to cut out with machinery. On a house scale they are simply the single most common thing we pull out of a blocked lateral.
The rest of the list
- Paper towel and tissues — engineered to stay intact when wet, which is precisely the wrong property
- Cotton buds, cotton wool and dental floss — floss is worse than it looks, it tangles and forms a net that catches everything else
- Feminine hygiene products — designed to absorb and expand
- Nappies and wipes of every description
- Cat litter, including the varieties marketed as flushable
- Medication — it does not break down and it ends up in the water table
- Cooking grease — liquid when poured, solid at pipe temperature
- Anything described as biodegradable without a timescale attached. Everything is biodegradable eventually
The kitchen sink, while we are here
- Cooking grease and oil. Pour into a jar, let it set, bin it
- Coffee grounds — they clump and settle in the trap and the horizontal run
- Eggshells and fibrous vegetable peelings, disposal unit or not. A disposal shreds; it does not digest
- Rice and pasta, which continue to swell in standing water
A bin next to the sink prevents more call-outs than any product you can buy.
Need a hand with this?
Drain Cleaning
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